Internet Draft        SONET/SDH Objects          July 26, 1996


			  Definitions of Managed Objects
			 for the SONET/SDH Interface Type

				  July 26, 1996


			      AToM MIB Working Group

				    Kaj Tesink
			   Bell Communications Research
			     331 Newman Springs Road
			       Red Bank, NJ  07701

			       kaj@cc.bellcore.com

                       <draft-ietf-atommib-sonetng-01.txt>
                             

	  1.  Status of this Memo

	  This document is an Internet Draft.  Internet Drafts are
	  working documents of the Internet Engineering Task Force
	  (IETF), its Areas, and its Working Groups. Note that other
	  groups may also distribute working documents as Internet
	  Drafts.

	  Internet Drafts are draft documents valid for a maximum of six
	  months. Internet Drafts may be updated, replaced, or obsoleted
	  by other documents at any time.  It is not appropriate to use
	  Internet Drafts as reference material or to cite them other
	  than as a "working draft" or "work in progress."

	  Please check the I-D abstract listing contained in each
	  Internet Draft directory to learn the current status of this
	  or any other Internet Draft.

	  Distribution of this document is unlimited.













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	  2.  Abstract

	  This memo defines an experimental portion of the Management
	  Information Base (MIB) for use with network management
	  protocols in TCP/IP-based internets.  In particular, it
	  defines objects for managing Synchronous Optical
	  Network/Synchronous Digital Hierarchy (SONET/SDH) objects.
	  This document is a companion document with Definitions of
	  Managed Objects for the DS1/E1 and DS3/E3 Interface Types,
	  RFC1406 [14] and RFC1407 [13].

	  This memo specifies a MIB module in a manner that is both
	  compliant to the SNMPv2 SMI, and semantically identical to the
	  peer SNMPv1 definitions.




































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	  3.  The SNMP Network Management Framework

	  The SNMP Network Management Framework presently consists of
	  three major components.  They are:

	  0    RFC 1902 which defines the SMI, the mechanisms used for
	       describing and naming objects for the purpose of
	       management.

	  0    RFC 1213 defines MIB-II, the core set of managed objects
	       for the Internet suite of protocols.

	  0    RFC 1157 and RFC 1905 which define two versions of the
	       protocol used for network access to managed objects.

	  The Framework permits new objects to be defined for the
	  purpose of experimentation and evaluation.

































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	  4.  Objects

	  Managed objects are accessed via a virtual information store,
	  termed the Management Information Base or MIB.  Objects in the
	  MIB are defined using the subset of Abstract Syntax Notation
	  One (ASN.1) [7] defined in the SMI.  In particular, each
	  object has a name, a syntax, and an encoding.  The name is an
	  object identifier, an administratively assigned name, which
	  specifies an object type.  The object type together with an
	  object instance serves to uniquely identify a specific
	  instantiation of the object.  For human convenience, we often
	  use a textual string, termed the OBJECT DESCRIPTOR, to also
	  refer to the object type.

	  The syntax of an object type defines the abstract data
	  structure corresponding to that object type.  The ASN.1
	  language is used for this purpose.  However, the SMI RFC 1902
	  purposely restricts the ASN.1 constructs which may be used.
	  These restrictions are explicitly made for simplicity.

	  The encoding of an object type is simply how that object type
	  is represented using the object type's syntax.  Implicitly
	  tied to the notion of an object type's syntax and encoding is
	  how the object type is represented when being transmitted on
	  the network.  The SMI specifies the use of the basic encoding
	  rules of ASN.1 [8], subject to the additional requirements
	  imposed by the SNMP.

	  4.1.  Format of Definitions

	  Section 6 contains contains the specification of all object
	  types contained in this MIB module.  The object types are
	  defined using the conventions defined in the SMI, as amended
	  by the extensions specified in the SNMPv2 SMI.
















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	  5.  Overview

	  These objects are used when the particular media being used to
	  realize an interface is a SONET/SDH interface.  At present,
	  this applies to these values of the ifType variable in the
	  Internet-standard MIB:

	       sonet (39), sonetPath (50), sonetVT (51)

	  The definitions contained herein are based on the SONET/SDH
	  specifications in ANSI T1.105 and T1.106-1988 [9, 9a, 10] and
	  CCITT G.707, 708, 709, and G.783 [15-18].

	  5.1.  Use of the ifTable

	  This section specifies how the MIB II interfaces group, as
	  defined in [12], is used for SONET/SDH interfaces.  The
	  SONET/SDH layers support several multiplexing possibilities.

	  For example in SONET, an Synchronous Transport Signal 3 (STS-
	  3) has 3 SONET Paths, and a STS-3c has 1 SONET Path. Another
	  example could be a STS-12 having 4 SONET STS-3c Paths.
	  Similarly, a SONET Synchronous Payload Envelope (SPE) can
	  carry many Virtual Tributaries (VTs), for example, one SONET
	  SPE can carry 28 VT1.5s.  It is important to note that an SPE
	  and a VT in SONET is collectively referred to as a Virtual
	  Container (VC) in SDH.  Also, an STS is called Synchronous
	  Transport Module (STM) in SDH.

	  Not all SONET/SDH equipment terminate all SONET/SDH layers.
	  For example, an SONET/SDH STE regenerator terminates SONET/SDH
	  Sections only, and is transparent for all layers above that.
	  SONET/SDH Add-Drop multiplexers and Digital Cross Connect
	  Systems terminate SONET/SDH Lines. SONET/SDH Terminal
	  Multiplexers may also terminate SONET/SDH Paths and VTs/VCs.

	  MIB II [6], as extended by [12], accommodates these cases by
	  appropriate use of the MIB II system group, and the interfaces
	  group. The system group can name and describe the type of
	  managed resource. The interfaces group defines which SONET/SDH
	  layers apply, how these layers are configured and multiplexed.
	  This is achieved by proper representation of SONET/SDH Layers
	  by ifEntries as defined in [12], as follows:







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			_____________________________
		       |             |          |    |  >
		       |             |          |    |  |
		       |    VT 1     |..........|VT K|   > K ifEntries
		       |             |          |    |  |
		       |_____________|__________|____|  >
		       |               |      |      |  >
		       |               |      |      |  |
		       |    Path 1     |......|Path L|   > L ifEntries
		       |               |      |      |  |
		       |_______________|______|______|  >
		       |                             |  >
		       |                             |  |
		       |    Line                     |  |
		       |                             |  |
		       |_____________________________|  |
		       |                             |  |
		       |                             |  |
		       |    Section Layer            |   > 1 ifEntry
		       |                             |  |
		       |_____________________________|  |
		       |                             |  |
		       |                             |  |
		       |    Physical Medium Layer    |  |
		       |                             |  |
		       |_____________________________|  >

		       Use of ifTable for a SONET/SDH port

	  The exact configuration and multiplexing of the layers is
	  maintained in the ifStackTable [12].

	  5.2.  Use of ifTable for SONET/SDH Medium/Section/Line Layer

	  Only the ifGeneralInformationGroup needs to be supported.

	  ifTable Object    Use for combined SONET/SDH
			    Medium/Section/Line Layer
	  ======================================================================
	   ifIndex           Interface index.

	   ifDescr           SONET/SDH Medium/Section/Line

	   ifType            sonet(39)






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	   ifSpeed           Speed of line rate for SONET/SDH,
			     (e.g., 155520000 bps).

	   ifPhysAddress     The value of the Circuit Identifier.
			     If no Circuit Identifier has been assigned
			     this object should have an octet string with
			     zero length.

	   ifAdminStatus     Supports read-only access.
			     The desired administrative status of the
			     interface.

	   ifOperStatus      The value testing(3) is not used.
			     This object assumes the value down(2),
			     if the objects sonetSectionCurrentStatus
			     and sonetLineCurrentStatus have
			     any other value than sonetSectionNoDefect(1)
			     and sonetLineNoDefect(1), respectively.

	   ifLastChange      sysUpTime at the last change in ifOperStatus.

	   ifName            Textual name of the interface or an OCTET STRING
			     of zero length.

	   ifLinkUpDownTrapEnable   Set to enabled(1).
				    Supports read-only access.

	   ifHighSpeed       Speed of line in Mega-bits per second
			     (e.g., 155 Mbps)

	   ifConnectorPresent Set to true(1).

	   ifAlias            The (non-volatile) alias name for this interface
			      as assigned by the network manager.

	  5.3.  Use of ifTable for SONET/SDH Paths

	  Only the ifGeneralInformationGroup needs to be supported.

	  ifTable Object    Use for SONET/SDH Paths
	  =========================================
	   ifIndex           Interface index.

	   ifDescr           SONET/SDH Path

	   ifType            sonetPath(50)





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	   ifSpeed           set to speed of SONET/SDH path
			     (e.g., an STS-1 path has a
			     rate of 50112000 bps.)

	   ifPhysAddress     Circuit Identifier or OCTET STRING of zero
	   length.

	   ifAdminStatus     Supports read-only access.
			     The desired administrative status of the
			     interface.

	   ifOperStatus      This object assumes the value down(2),
			     if the object sonetPathCurrentStatus has
			     any other value than sonetPathNoDefect(1).

	   ifLastChange      sysUpTime at the last change in ifOperStatus.

	   ifName            Textual name of the interface or an OCTET STRING
			     of zero length.

	   ifLinkUpDownTrapEnable   Default value is disabled(2).
				    Just read-only access may be supported.

	   ifHighSpeed       Set to rate of SONET/SDH path
			     in Mega-bits per second.

	   ifConnectorPresent Set to false(2).

	   ifAlias            The (non-volatile) alias name for this interface
			      as assigned by the network manager.


	  5.4.  Use of ifTable for SONET/SDH VTs/VCs

	  Only the ifGeneralInformationGroup needs to be supported.

	  ifTable Object    Use for SONET/SDH VTs/VCs
	  ===========================================
	   ifIndex           Interface index.

	   ifDescr           SONET/SDH VT/VC

	   ifType            sonetVT(51)

	   ifSpeed           Set to speed of VT/VC
			     (e.g., a VT1.5 has a rate of
			     1728000 bps.)





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	   ifPhysAddress     Circuit Identifier or OCTET STRING of zero
	   length.

	   ifAdminStatus     Supports read-only access.
			     The desired administrative status of the
			     interface.

	   ifOperStatus      This object assumes the value down(2),
			     if the object sonetVTCurrentStatus has
			     any other value than sonetVTNoDefect(1).

	   ifLastChange      sysUpTime at the last change in ifOperStatus.

	   ifName            Textual name of the interface or an OCTET STRING
			     of zero length.

	   ifLinkUpDownTrapEnable   Default value is disabled(2).
				    Just read-only access may be supported.

	   ifHighSpeed       Set to rate of VT in Mega-bits per second.

	   ifConnectorPresent Set to false(2).

	   ifAlias            The (non-volatile) alias name for this interface
			      as assigned by the network manager.


	  5.5.  SONET/SDH Terminology

	  The terminology used in this document to describe error
	  conditions on a SONET circuit as monitored by a SONET system
	  are from the T1.231 [20].  The terminology used in this
	  document to describe error conditions on a SDH circuit as
	  monitored by a SDH system are from the CCITT G.783 [18].  Only
	  the SONET Performance Monitoring terminology is defined in
	  this document.  The definitions for SDH Performance Monitoring
	  terms are similar but not identical, and they can be found in
	  [18].  If the definition in this document does not match the
	  definition in the T1.231 document, the implementer should
	  follow the definition described in this document.  In some
	  cases other or additional references are used as compared with
	  the ones cited above. This will be indicated in the text.

	  Section Loss Of Frame Failure (Out of Frame Event, Severely
	       Errored Frame Defect)
	       An Out of Frame (OOF) event (or Severely Errored Frame
	       defect) is the occurrence of four contiguous errored





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	       frame alignment words.  A frame alignment work occupies
	       the A1 and A2 bytes of an STS frame, and is defined in
	       T1.105.  The SEF defect is terminated when two contiguous
	       error-free frame words are detected.  Any implementation
	       of the frame recovery circuitry which achieves
	       realignment following an OOF within the 250 microsecond
	       (two frames) interval implied by this definition is
	       acceptable.

	       An Loss of Frame (LOF) defect is declared when an OOF/SEF
	       defect persists for a period of 3 milliseconds.  The LOF
	       defect is terminated when the incoming signal remains
	       continuously in-frame for a period of 1 ms to 3 ms.

	       An LOF failure is declared when the LOF defect persists
	       for a period of 2.5 +/- 0.5 seconds, except when an LOS
	       defect or failure is present.  The LOF failure is cleared
	       when the LOS failure is declared, or when the LOF defect
	       is absent for 10 +/- 0.5 seconds.

	  Loss of Signal
	       The Loss of Signal (LOS) defect is declared when no
	       transitions are detected on the incoming signal (before
	       descrambling).  The LOS defect is detected  upon
	       observing 2.3 to 100 microseconds of no transitions.  The
	       LOS defect is cleared after a 125 microsecond interval
	       (one frame) during which no LOS defect is detected.

	       The LOS failure is declared when the LOS defect persists
	       for a period of 2.5 +/- 0.5 seconds, or if LOS defect is
	       present when the criteria for LOF failure declaration
	       have been met.  The LOS failure is cleared when the LOS
	       defect is absent for a period of 10 +/- 0.5 seconds.
	       Declaration of LOS failure clears any existing LOF
	       failure.  Clearing the LOS failure allows immediate
	       declaration of the LOF failure if conditions warrant.

	  STS-Path Loss of Pointer
	       An Loss of Pointer (LOP) defect is declared when either a
	       valid pointer is not detected in eight consecutive
	       frames, or when eight consecutive frames are detected
	       with the New Data Flag (NDF) set to "1001" without a
	       valid concatenation indicator (see ANSI T1.105).  A LOP
	       defect is terminated when either a valid pointer with a
	       normal NDF set to "0110", or a valid concatenation





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	       indicator is detected for three contiguous frames.
	       Incoming STS-Path AIS shall not result in the declaration
	       of a LOP defect.

	       A STS-Path LOP failure is declared when the STS-Path LOP
	       defect persists for a period of 2.5 +/- 0.5 seconds.  A
	       STS-Path LOP failure is cleared when the STS-Path LOP
	       defect is absent for 10 +/- 0.5 seconds.

	  VT Loss of Pointer
	       A VT LOP defect is declared when either a valid pointer
	       is not detected in eight consecutive VT superframes, or
	       when eight consecutive VT superframes are detected with
	       the NDF set to "1001" without a valid concatenation
	       indicator.  A VT LOP defect is terminated when either a
	       valid pointer with a normal NDF set to "0110", or a valid
	       concatenation indicator is detected for three contiguous
	       VT superframes.  Incoming VT-Path AIS shall not result in
	       declaring a VT LOP defect.

	       A VT LOP failure is declared when the VT LOP defect
	       persists for 2.5 +/- 0.5 seconds.  A VT LOP failure is
	       cleared when the VT LOP defect is absent for 10 +/- 0.5
	       seconds.

	  Line Alarm Indication Signal
	       A Line Alarm Indication Signal (L-AIS) is defined in ANSI
	       T1.105.  The following criteria are specific to the L-AIS
	       defect:

	       --  Line AIS defect is detected as a "111" pattern in
	       bits 6, 7, and 8 of the K2 byte in five consecutive
	       frames.

	       --  Line AIS defect is terminated when bits 6, 7, and 8
	       of the K2 byte do not contain the code "111" for five
	       consecutive frames.

	       A Line AIS failure is declared when the Line AIS defect
	       persists for a period of 20.5 +/- 0.5 seconds.  A Line
	       AIS failure is cleared when the Line AIS defect is absent
	       for 10 +/- 0.5 seconds.

	  STS-Path Alarm Indication Signal
	       The STS-Path Alarm Indication Signal (AIS) is defined in





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	       ANSI T1.105 as all ones in bytes H1, H2, and H3 as well
	       as all ones in the entire STS SPE.  The following
	       criteria are specific to the STS-Path AIS defect:

	       -- STS-Path AIS defect is detected as all ones in bytes
	       H1 and H2 in three contiguous frames.

	       -- The STS-Path AIS defect is terminated when a valid STS
	       Pointer is detected with the NDF set to "1001" (inverted)
	       for one frame, or  "0110" (normal) for three contiguous
	       frames.

	       A STS-Path AIS failure is declared when the STS-Path AIS
	       defect persists for 2.5 +/- 0.5 seconds.  A STS-Path AIS
	       failure is cleared when the STS-Path AIS defect is absent
	       for 10 +/- 0.5 seconds.

	  VT-Path Alarm Indication Signal
	       The VT-Path Alarm Indication Signal (AIS) is only
	       applicable for VTs in the floating mode of operation.
	       VT-Path AIS is used to alert the downstream VT Path
	       Terminating Entity (PTE) of an upstream failure.  Upon
	       detection of a failure, Line AIS, or STS-Path AIS, an STS
	       PTE will generate downstream VT-Path AIS if the STS
	       Synchronous Payload Envelope (SPE) is carrying floating
	       VTs.  VT-Path AIS is specified in ANSI T1.105 as all ones
	       in bytes V1, V2, V3, and V4, as well as all ones in the
	       entire VT SPE.  The following criteria are specific to
	       VT-Path AIS defect:

	       --  VT-Path AIS defect is detected by a VT PTE as all
	       ones in bytes V1 and V2 in three contiguous VT
	       superframes.

	       --  VT-Path AIS defect is terminated when valid VT
	       pointer with a valid VT size is detected with the NDF set
	       to "1001" (inverted) for one VT superframe, or "0110"
	       (normal) for three contiguous VT superframes are
	       detected.

	       A VT-Path AIS failure is declared when the VT-Path AIS
	       defect persists for 2.5 +/- 0.5 seconds.  A VT-Path AIS
	       failure is cleared when the VT-Path AIS defect is absent
	       for 10 +/- 0.5 seconds.






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	  Line Remote Defect Indication
	       Line Remote Defect Indication (RDI) (aka Line FERF)
	       signal is the occurrence of a "110" pattern in bit
	       positions 6, 7, and 8 of the K2 byte in STS-1 #1 of the
	       STS-N signal.  Line RDI is defined in ANSI T1.105.  The
	       following criteria are specific to Line RDI defect:

	       --  Line RDI defect is a "110" code in bits 6, 7, and 8
	       of the K2 byte of in STS-1 #1 in five consecutive frames.

	       --  Line RDI defect is terminated when any code other
	       than "110" is detected in bits 6, 7, and 8 of the K2 byte
	       in five consecutive frames.

	       A Line Remote Failure Indication (RFI) failure is
	       declared when the incoming Line RDI defects lasts for 2.5
	       +/- 0.5 seconds.  The Line RFI failure is cleared when no
	       Line RDI defects are detected for 10 +/- 0.5 seconds.

	  STS-Path Remote Defect Indication
	       STS-Path RDI (aka STS-Path FERF) signal shall be
	       generated within 100 milliseconds by the STS PTE upon
	       detection of an AIS or LOP defect.  Transmission of the
	       STS-Path RDI signal shall cease within 100 milliseconds
	       when the STS PTE no longer detects STS-Path AIS or STS-
	       Path LOP defect.  The STS-Path RDI  shall accurately
	       report the presence or absence of STS-Path AIS or STS-
	       Path LOP defects.  STS-Path RDI defect is defined in ANSI
	       T1.105.  The following requirements are specific to the
	       STS-Path RDI defect:

	       --  STS-Path RDI is detected by all STS PTEs.  STS-Path
	       RDI is detected by the upstream STS PTE as a "1" in bit
	       five of the Path Status byte (G1) for five contiguous
	       frames.

	       --  Removal of STS-Path Remote Defect Indication is
	       detected by a "0" in bit 5 of the G1 byte in five
	       contiguous frames.

	       A STS-Path Remote Failure Indication (RFI) failure is
	       declared when the incoming STS-Path RDI defects lasts for
	       2.5 +/- 0.5 seconds.  The STS-Path RFI failure is cleared
	       when no STS-Path RDI defects are detected for 10 +/- 0.5
	       seconds.





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	  VT-Path Remote Defect Indication
	       VT Path RDI (aka VT Path FERF) signal shall be generated
	       within 100 milliseconds by the VT PTE upon detection of a
	       VT-Path AIS or LOP defect.  Transmission of the VT-Path
	       RDI signal shall cease within 100 milliseconds when the
	       VT PTE no longer detects VT-Path AIS or VT-Path LOP
	       defect.  The VT-Path RDI  shall accurately report the
	       presence or absence of VT-Path AIS or VT-Path LOP
	       defects.  VT-Path RDI defect is defined in ANSI T1.105.
	       The following requirements are specific to VT-Path RDI
	       defect:

	       --  VT-Path RDI defect is the occurrence of a "1" in bit
	       4 of the VT-Path Overhead byte (V5) in five contiguous
	       frames.

	       --  VT-Path RDI defect is terminated when a "0" is
	       detected in bit 4 of the VT-Path Overhead byte (V5) for
	       five contiguous frames.

	       A VT-Path Remote Failure Indication (RFI) (derived)
	       failure is declared when the incoming VT-Path RDI defects
	       lasts for 2.5 +/- 0.5 seconds.  The VT-Path RFI failure
	       is cleared when no VT-Path RDI defects are detected for
	       10 +/- 0.5 seconds.

	  VT-Path Remote Failure Indication
	       The VT-Path RFI signal is only required for the case of
	       byte synch mapped DS1s where the DS1 frame bit is not
	       mapped.  The VT-Path RFI is specified in ANSI T1.105,
	       where it is currently called VT path yellow.  When
	       provided, the VT-Path RFI signal is used to indicate the
	       occurrence of far-end failures.  When the VT-Path RFI is
	       not provided, far-end failures are derived from local
	       timing of the VT-Path RDI defect.  The VT-Path RFI
	       failure is declared within 5 ms of detecting the incoming
	       VT-Path RFI Signal.  The VT-Path Remote Failure
	       Indication (RFI) failure is cleared within 50 ms of
	       detecting the removal of the incoming VT-Path RFI signal.

	  Coding Violation
	       Coding Violations (CV) are Bit Interleaved Parity (BIP)
	       errors that are detected in the incoming signal.  CV
	       counters are incremented for each BIP error detected.
	       That is, each BIP-8 can detect up to eight errors per





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	       STS-N frame, with each error incrementing the CV counter.
	       Section CVs shall be collected using the BIP-8 in the B1
	       byte located in the Section Overhead of STS-1 #1.  Line
	       CVs shall be collected using the BIP-8s in B2 bytes
	       located in the Line Overhead of each STS-1 (since all CVs
	       on an STS-N line are counted together, this is equivalent
	       to counting each error in the BIP-8*N contained in the B2
	       bytes of the STS-N Line Overhead).  Thus, on an STS-N
	       signal, up to 8 x N CVs may occur in each frame.  Path
	       CVs shall be collected using the BIP-8 in the B3 byte of
	       the STS-Path Overhead of the STS SPE.  VT CVs shall be
	       collected using the BIP-2 in the V5 overhead byte of the
	       floating VT.

	  Errored Seconds
	       At each layer, an Errored Second (ES) is a second with
	       one or more Coding Violations at that layer OR one or
	       more incoming defects (e.g., SEF, LOS, AIS, LOP) at that
	       layer has occurred.

	  Severely Errored Seconds
	       According to [11, 20, 21, 23] at each layer, an Severely
	       Errored Second (SES) is a second with x or more CVs at
	       that layer, or a second during which at least one or more
	       incoming defects at that layer has occurred.  The values
	       of x  in RFC1595[19] were based on [11] and [21] (see
	       Appendix B). These values have subsequently been relaxed
	       in [20, 23]. In addition, according to G.826 [22] SESs
	       are measured as a percentage of errored blocks.

	       To deal with these sets of definitions this memo defines
	       an object sonetSESThresholdSet that determines the
	       correct interpretation of SES. For backward
	       compatibility, if this object is not implemented the
	       interpretation of Appendix B shall apply.  Otherwise, a
	       more recent interpretation is suggested.  An agent is not
	       required to support all sets of definitions.

	       Note that if a manager changes the value of this object
	       all SES statistics collected prior to this change shall
	       be invalidated.

	  Severely Errored Framing Seconds
	       A Severely Errored Framing Second (SEFS) is a seconds
	       with containing one or more SEF events.  This counter is





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	       only counted at the Section Layer.

	  Unavailable Seconds
	       At the Line, Path, and VT layers, an unavailable second
	       is calculated by counting the number of seconds that the
	       interface is unavailable.  At each layer, the SONET/SDH
	       interface is said to be unavailable at the onset of 10
	       contiguous SESs.  The 10 SESs are included in unavailable
	       time.  Once unavailable, the SONET/SDH interface becomes
	       available at the onset of 10 contiguous seconds with no
	       SESs.  The 10 seconds with no SESs are excluded from
	       unavailable time.  With respect to the SONET/SDH error
	       counts at each layer, all counters at that layer are
	       incremented while the SONET/SDH interface is deemed
	       available at that layer.  While the interface is deemed
	       unavailable at that layer, the only count that is
	       incremented is UASs at that layer.

	       Note that this definition implies that the agent cannot
	       determine until after a ten second interval has passed
	       whether a given one-second interval belongs to available
	       or unavailable time.  If the agent chooses to update the
	       various performance statistics in real time then it must
	       be prepared to retroactively reduce the ES, SES, and SEFS
	       counts by 10 and increase the UAS count by 10 when it
	       determines that available time has been entered.  It must
	       also be prepared to reduce the CV count by the number of
	       violations counted since the onset of unavailable time.
	       The agent must be similarly prepared to retroactively
	       decrease the UAS count by 10 and increase the ES and CV
	       counts as necessary upon entering available time.  A
	       special case exists when the 10 second period leading to
	       available or unavailable time crosses a 900 second
	       statistics window boundary, as the foregoing description
	       implies that the CV, ES, SES, SEFS, and UAS counts the
	       PREVIOUS interval must be adjusted.  In this case
	       successive GETs of the affected sonetPathIntervalSES and
	       sonetPathIntervalUAS objects (and the analogous Line and
	       VT objects also) objects will return differing values if
	       the first GET occurs during the first few seconds of the
	       window.

	       According to ANSI T1.231 unavailable time begins at the
	       _onset_ of 10 contiguous severely errored seconds -- that
	       is, unavailable time starts with the _first_ of the 10





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	       contiguous SESs.  Also, while an interface is deemed
	       unavailable all counters for that interface are frozen
	       except for the UAS count.  It follows that an
	       implementation which strictly complies with this standard
	       must _not_ increment any counters other than the UAS
	       count -- even temporarily -- as a result of anything that
	       happens during those 10 seconds.  Since changes in the
	       signal state lag the data to which they apply by 10
	       seconds, an ANSI-compliant implementation must pass the
	       one-second statistics through a 10-second delay line
	       prior to updating any counters.  That can be done by
	       performing the following steps at the end of each one
	       second interval.

	  i)   Read near/far end CV counter and alarm status flags from
	       the hardware.

	  ii)  Accumulate the CV counts for the preceding second and
	       compare them to the ES and SES threshold for the layer in
	       question.  Update the signal state and shift the one-
	       second CV counts and ES/SES flags into the 10-element
	       delay line.  Note that far-end one-second statistics are
	       to be flagged as "absent" during any second in which
	       there is an incoming defect at the layer in question or
	       at any lower layer.

	  iii) Update the current interval statistics using the signal
	       state from the _previous_ update cycle and the one-second
	       CV counts and ES/SES flags shifted out of the 10-element
	       delay line.

	       This approach is further described in Appendix A. An
	       agent may choose to use this approach in lieu of
	       retroactive adjustments to the counters.

	       In any case, a linkDown trap shall be sent only after the
	       agent has determined for certain that the unavailable
	       state has been entered, but the time on the trap will be
	       that of the first UAS (i.e., 10 seconds earlier).  A
	       linkUp trap shall be handled similarly.

	  Unequipped
	       If a Path or VT connection is not provisioned (idle) the
	       SONET equipment will signal this state by transmitting
	       the Path or VT Signal Label as follows:





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	       - byte C2 of the STS Path Overhead equal to 0 for an
	       unequipped Path,
	       - byte V5 of the VT Path Overhead equal to 0 for an
	       unequipped VT.

	  Signal Label Mismatch
	       A Path or VT connection is not correctly provisioned if a
	       received Path or VT Signal Label mismatch occurs.  A
	       received Signal Label is considered mismatched if it does
	       not equal either the locally provisioned value or the
	       value 'equipped non-specific' (1 hex). Note that any
	       received non-zero Signal Label is considered a locally
	       provisioned value of 'equipped non-specific'.  Only in-
	       service, provisioned Path Terminating equipment can
	       detect mismatched Signal labels. It is considered
	       provisioned if it has been configured for a mapping and
	       has been assigned signals to and from which the mapping
	       takes place.  While a Path is unequipped or has
	       mismatched signal labels ES/SES counts continue, but
	       these conditions do not themselves contribute to ES/SES.

	  Circuit Identifier
	       This is a character string specified by the circuit
	       vendor, and is useful when communicating with the vendor
	       during the troubleshooting process.

























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	  6.  Object Definitions

	  SONET-MIB DEFINITIONS ::= BEGIN


	  IMPORTS
	      MODULE-IDENTITY, OBJECT-TYPE,
	      Integer32
		    FROM SNMPv2-SMI
	      DisplayString, TruthValue
		    FROM SNMPv2-TC
	      MODULE-COMPLIANCE, OBJECT-GROUP
		    FROM SNMPv2-CONF
	      ifIndex, transmission
		    FROM RFC1213-MIB
	      PerfCurrentCount, PerfIntervalCount
		    FROM PerfHist-TC-MIB;

	  --  This is the MIB module for the SONET/SDH Interface objects.


	  sonetMIB MODULE-IDENTITY
	      LAST-UPDATED "9607260000Z"
	      ORGANIZATION "IETF AToM MIB Working Group"
	      CONTACT-INFO
		"Kaj Tesink
		 Bell Communications Research
		 Tel: (908) 758-5254
		 Fax: (908) 758-4196
		 E-mail: kaj@cc.bellcore.com."
	      DESCRIPTION
		   "The MIB module to describe
		   SONET/SDH interfaces objects."
	      ::= { transmission 39 }


	  --  This is the MIB module for the SONET/SDH objects

	  sonetObjects      OBJECT IDENTIFIER ::= { sonetMIB 1 }

	  sonetObjectsPath  OBJECT IDENTIFIER ::= { sonetMIB 2 }

	  sonetObjectsVT    OBJECT IDENTIFIER ::= { sonetMIB 3 }







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	  -- groups in the SONET/SDH MIB module

	  sonetMedium        OBJECT IDENTIFIER ::= { sonetObjects 1 }

	  sonetSection       OBJECT IDENTIFIER ::= { sonetObjects 2 }

	  sonetLine          OBJECT IDENTIFIER ::= { sonetObjects 3 }

	  sonetFarEndLine    OBJECT IDENTIFIER ::= { sonetObjects 4 }

	  sonetPath          OBJECT IDENTIFIER ::= { sonetObjectsPath 1 }

	  sonetFarEndPath    OBJECT IDENTIFIER ::= { sonetObjectsPath 2 }

	  sonetVT            OBJECT IDENTIFIER ::= { sonetObjectsVT 1 }

	  sonetFarEndVT      OBJECT IDENTIFIER ::= { sonetObjectsVT 2 }

































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	  -- the SONET/SDH Medium group

	  -- SONET/SDH interfaces for some applications may be electrical
	  -- interfaces and not optical interfaces.  This group handles
	  -- the configuration information for both optical SONET/SDH
	  -- interfaces
	  -- and electrical SONET/SDH interfaces.

	  sonetMediumTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetMediumEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "The SONET/SDH Medium table."
	       ::= { sonetMedium 1 }

	  sonetMediumEntry OBJECT-TYPE
	      SYNTAX  SonetMediumEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "An entry in the SONET/SDH Medium table."
	      INDEX   { ifIndex }
	       ::= { sonetMediumTable 1 }

	  SonetMediumEntry ::=
	      SEQUENCE {
		   sonetMediumType               INTEGER,
		   sonetMediumTimeElapsed        Integer32,
		   sonetMediumValidIntervals     Integer32,
		   sonetMediumLineCoding         INTEGER,
		   sonetMediumLineType           INTEGER,
		   sonetMediumCircuitIdentifier  DisplayString,
		   sonetMediumInvalidIntervals   Integer32
	      }


	  sonetMediumType OBJECT-TYPE
	      SYNTAX  INTEGER  {
			 sonet(1),
			 sdh(2)
		      }
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION





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		 "This variable identifies whether a SONET
		 or a SDH signal is used across this interface."
	      ::= { sonetMediumEntry 1 }

	  sonetMediumTimeElapsed OBJECT-TYPE
	      SYNTAX  Integer32 (1..900)
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The number of seconds, including partial
		 seconds, that have elapsed since the beginning of
		 the current error-measurement period."
	      ::= { sonetMediumEntry 2 }

	  sonetMediumValidIntervals OBJECT-TYPE
	      SYNTAX  Integer32 (0..96)
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The number of previous intervals for which valid
		 data has been stored.  A SONET interface must be
		 capable of supporting at least n intervals.
		 The minimum value of n is 4.
		 The default of n is 32.
		 The maximum value of n is 96.
		 The value of this object will be n unless
		 the device was brought online within the last
		 (nx15) minutes, in which case the value will be the
		 number of complete 15 minute intervals the device has
		 been online. In the case where the agent
		 is a proxy, it is possible that some intervals
		 are unavailable.  In this case, this
		 interval is the maximum interval number for
		 which valid data is available."
	      ::= { sonetMediumEntry 3 }

	  sonetMediumLineCoding OBJECT-TYPE
	      SYNTAX  INTEGER {
			  sonetMediumOther(1),
			  sonetMediumB3ZS(2),
			  sonetMediumCMI(3),
			  sonetMediumNRZ(4),
			  sonetMediumRZ(5)
		      }
	      MAX-ACCESS  read-only





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	      STATUS  current
	      DESCRIPTION
		 "This variable describes the line coding for
		 this interface. The B3ZS and CMI are used for
		 electrical SONET/SDH signals (STS-1 and STS-3).
		 The Non-Return to Zero (NRZ) and the Return
		 to Zero are used for optical SONET/SDH signals."
	      ::= { sonetMediumEntry 4 }

	  sonetMediumLineType OBJECT-TYPE
	      SYNTAX  INTEGER {
			  sonetOther(1),
			  sonetShortSingleMode(2),
			  sonetLongSingleMode(3),
			  sonetMultiMode(4),
			  sonetCoax(5),
			  sonetUTP(6)
		      }
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable describes the line type for
		 this interface. The line types are
		 Short and Long Range
		 Single Mode fiber or Multi-Mode fiber interfaces,
		 and coax and UTP for electrical interfaces.  The
		 value sonetOther should be used when the Line Type is
		 not one of the listed values."
	      ::= { sonetMediumEntry 5 }

	  sonetMediumCircuitIdentifier OBJECT-TYPE
	      SYNTAX  DisplayString (SIZE (0..255))
	      MAX-ACCESS  read-write
	      STATUS  current
	      DESCRIPTION
		 "This variable contains the transmission
		 vendor's circuit identifier, for the
		 purpose of facilitating troubleshooting.
		 Note that the circuit identifier, if available,
		 is also represented by ifPhysAddress."
	      ::= { sonetMediumEntry 6 }

	  sonetMediumInvalidIntervals OBJECT-TYPE
	      SYNTAX  Integer32 (0..96)
	      MAX-ACCESS  read-only





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	      STATUS  current
	      DESCRIPTION
		 "The number of intervals for which no valid
		  data is available. This includes intervals
		  of which valid data has been lost, e.g., due
		  to restart of the agent."
	      ::= { sonetMediumEntry 7 }

	  sonetMediumLoopbackConfig OBJECT-TYPE
	      SYNTAX      BITS {
			    sonetNoLoop(0)
			    sonetFacilityLoop(1),
			    sonetTerminalLoop(2),
			    sonetOtherLoop(3) }
	      MAX-ACCESS  read-write
	      STATUS      current
	      DESCRIPTION
		 "The current loopback state of the SONET/SDH interface.  The
		  values mean:

		    sonetNoLoop
		       Not in the loopback state. A device that is not
		       capable of performing a loopback on this interface
		       shall always return this value.

		    sonetFacilityLoop
		       The received signal at this interface is looped back
		       out through the corresponding transmitter in the return
		       direction.

		    sonetTerminalLoop
		       The signal that is about to be transmitted is connected
		       to the associated incoming receiver.

		    sonetOtherLoop
		       Loopbacks that are not defined here."

	      ::= { sonetMediumEntry 8 }

	  sonetSESthresholdSet    OBJECT-TYPE
	      SYNTAX   INTEGER {
			 other(1),
			 bellcore1991(2),
			 ansi1993(3),
			 itu1995(4)





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				}
	      MAX-ACCESS      read-write
	      STATUS          current
	      DESCRIPTION
		"An enumerated integer indicating which
		 recognized set of SES thresholds that
		 the agent uses for determining severely
		 errored seconds and unavailable time.

		 other(1)
		   None of the following.

		 bellcore1991(2)
		   Bellcore TR-NWT-000253, 1991 [21], or
		   ANSI T1M1.3/93-005R2, 1993 [11].
		   See also Appendix B.

		 ansi1993(3)
		   ANSI T1.231, 1993 [20], or
		   Bellcore GR-253-CORE, Issue 2, 1995 [23]

		 itu1995(4)
		   ITU Recommendation G.826, 1995 [22].

		 If a manager changes the value of this
		 object then the SES statistics collected
		 prior to this change must be invalidated."
	       ::= { sonetMedium 2 }






















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	  -- the SONET/SDH Section group

	  -- this group consists of 2 tables:
	  -- - the SONET/SDH Section Current Table
	  -- - the SONET/SDH Section Interval Table



	  -- the SONET/SDH Section Current Table

	  -- The SONET/SDH Section
	  -- current table contains various statistics
	  -- being collected for the current 15 minute interval.

	  sonetSectionCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetSectionCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "The SONET/SDH Section Current table."
	       ::= { sonetSection 1 }

	  sonetSectionCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetSectionCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "An entry in the SONET/SDH Section Current table."
	      INDEX   { ifIndex }
	       ::= { sonetSectionCurrentTable 1 }

	  SonetSectionCurrentEntry ::=
	      SEQUENCE {
		  sonetSectionCurrentStatus   Integer32,
		  sonetSectionCurrentESs      PerfCurrentCount,
		  sonetSectionCurrentSESs     PerfCurrentCount,
		  sonetSectionCurrentSEFSs    PerfCurrentCount,
		  sonetSectionCurrentCVs      PerfCurrentCount
	      }


	  sonetSectionCurrentStatus OBJECT-TYPE
	      SYNTAX  Integer32 (1..6)
	      MAX-ACCESS  read-only
	      STATUS  current





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	      DESCRIPTION
		 "This variable indicates the
		 status of the interface.
		 The sonetSectionCurrentStatus
		 is a bit map represented
		 as a sum, therefore,
		 it can represent multiple defects
		 simultaneously.
		 The sonetSectionNoDefect should be
		 set if and only if
		 no other flag is set.

		 The various bit positions are:
		       1   sonetSectionNoDefect
		       2   sonetSectionLOS
		       4   sonetSectionLOF"
	       ::= { sonetSectionCurrentEntry 1 }

	  sonetSectionCurrentESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of Errored
		 Seconds encountered by a SONET/SDH
		 Section in the current 15 minute interval."
	       ::= { sonetSectionCurrentEntry 2 }

	  sonetSectionCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Severely Errored Seconds
		 encountered by a SONET/SDH Section in the current 15
		 minute interval."
	       ::= { sonetSectionCurrentEntry 3 }

	  sonetSectionCurrentSEFSs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of





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		 Severely Errored Framing Seconds
		 encountered by a SONET/SDH Section in the current
		 15 minute interval."
	      ::= { sonetSectionCurrentEntry 4 }

	  sonetSectionCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of Coding
		 Violations encountered by a
		 SONET/SDH Section in the current 15 minute interval."
	       ::= { sonetSectionCurrentEntry 5 }




































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	  -- the SONET/SDH Section Interval Table

	  -- The SONET/SDH Section Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetSectionIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetSectionIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "The SONET/SDH Section Interval table."
	       ::= { sonetSection 2 }

	  sonetSectionIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetSectionIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "An entry in the SONET/SDH Section Interval table."
	      INDEX   { ifIndex,
			sonetSectionIntervalNumber }
	       ::= { sonetSectionIntervalTable 1 }

	  SonetSectionIntervalEntry ::=
	      SEQUENCE {
		   sonetSectionIntervalNumber  Integer32,
		   sonetSectionIntervalESs     PerfIntervalCount,
		   sonetSectionIntervalSESs    PerfIntervalCount,
		   sonetSectionIntervalSEFSs   PerfIntervalCount,
		   sonetSectionIntervalCVs     PerfIntervalCount,
		   sonetSectionIntervalValidData  TruthValue
	      }


	  sonetSectionIntervalNumber OBJECT-TYPE
	      SYNTAX  Integer32 (1..96)
	      MAX-ACCESS  not-accessible
	      STATUS  current





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	      DESCRIPTION
		"A number between 1 and 96, which identifies the
		interval for which the set of statistics is available.
		The interval identified by 1 is the most recently
		completed 15 minute interval,
		and the interval identified
		by N is the interval immediately preceding the
		one identified
		by N-1."
	       ::= { sonetSectionIntervalEntry 1 }

	  sonetSectionIntervalESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Errored Seconds encountered
		 by a SONET/SDH Section in a
		 particular 15-minute interval
		 in the past 24 hours."
	       ::= { sonetSectionIntervalEntry 2 }

	  sonetSectionIntervalSESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Severely Errored Seconds
		 encountered by a SONET/SDH Section in a
		 particular 15-minute interval
		 in the past 24 hours."
	      ::= { sonetSectionIntervalEntry 3 }

	  sonetSectionIntervalSEFSs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Severely Errored Framing Seconds
		 encountered by a SONET/SDH Section in a
		 particular 15-minute interval
		 in the past 24 hours."





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	      ::= { sonetSectionIntervalEntry 4 }

	  sonetSectionIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of Coding
		 Violations encountered by a
		 SONET/SDH Section in a particular 15-minute interval
		 in the past 24 hours."
	      ::= { sonetSectionIntervalEntry 5 }

	  sonetSectionIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetSectionIntervalEntry 6 }





























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	  -- the SONET/SDH Line group

	  -- this group consists of 2 tables:
	  -- - the SONET/SDH Line Current Table
	  -- - the SONET/SDH Line Interval Table


	  -- the SONET/SDH Line Current Table

	  -- The SONET/SDH Line
	  -- current table contains various statistics
	  -- being collected for the current 15 minute interval.

	  sonetLineCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetLineCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		"The SONET/SDH Line Current table."
	      ::= { sonetLine 1 }

	  sonetLineCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetLineCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		"An entry in the SONET/SDH Line Current table."
	      INDEX   { ifIndex }
	      ::= { sonetLineCurrentTable 1 }

	  SonetLineCurrentEntry ::=
	      SEQUENCE {
		   sonetLineCurrentStatus    Integer32,
		   sonetLineCurrentESs       PerfCurrentCount,
		   sonetLineCurrentSESs      PerfCurrentCount,
		   sonetLineCurrentCVs       PerfCurrentCount,
		   sonetLineCurrentUASs      PerfCurrentCount
	       }


	  sonetLineCurrentStatus OBJECT-TYPE
	      SYNTAX  Integer32 (1..6)
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION





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		 "This variable indicates the
		 status of the interface.
		 The sonetLineCurrentStatus
		 is a bit map represented
		 as a sum, therefore,
		 it can represent multiple defects
		 simultaneously.
		 The sonetLineNoDefect should be
		 set if and only if
		 no other flag is set.

		 The various bit positions are:
		  1   sonetLineNoDefect
		  2   sonetLineAIS
		  4   sonetLineRDI"
	       ::= { sonetLineCurrentEntry 1 }

	  sonetLineCurrentESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Errored
	       Seconds encountered by a SONET/SDH
	       Line in the current 15 minute interval."
	      ::= { sonetLineCurrentEntry 2 }

	  sonetLineCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Severely Errored Seconds
	       encountered by a SONET/SDH Line in the current 15
	       minute
	       interval."
	      ::= { sonetLineCurrentEntry 3 }

	  sonetLineCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Coding





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	       Violations encountered by a
	       SONET/SDH Line in the current 15 minute interval."
	      ::= { sonetLineCurrentEntry 4 }

	  sonetLineCurrentUASs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Unavailable Seconds
	       encountered by a SONET/SDH Line in the current 15
	       minute
	       interval."
	      ::= { sonetLineCurrentEntry 5 }



































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	  -- the SONET/SDH Line Interval Table

	  -- The SONET/SDH Line Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetLineIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetLineIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "The SONET/SDH Line Interval table."
	       ::= { sonetLine 2 }

	  sonetLineIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetLineIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "An entry in the SONET/SDH Line Interval table."
	     INDEX   { ifIndex,
		       sonetLineIntervalNumber }
	     ::= { sonetLineIntervalTable 1 }

	  SonetLineIntervalEntry ::=
	      SEQUENCE {
		  sonetLineIntervalNumber    Integer32,
		  sonetLineIntervalESs       PerfIntervalCount,
		  sonetLineIntervalSESs      PerfIntervalCount,
		  sonetLineIntervalCVs       PerfIntervalCount,
		  sonetLineIntervalUASs      PerfIntervalCount,
		  sonetLineIntervalValidData TruthValue
	      }


	  sonetLineIntervalNumber OBJECT-TYPE
	      SYNTAX  Integer32 (1..96)
	      MAX-ACCESS  not-accessible
	      STATUS  current





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	      DESCRIPTION
		  "A number between 1 and 96, which identifies the
		  interval for which the set of statistics is available.
		  The interval identified by 1 is the most recently
		  completed 15 minute interval,
		  and the interval identified
		  by N is the interval immediately preceding the
		  one identified
		  by N-1."
	       ::= { sonetLineIntervalEntry 1 }

	  sonetLineIntervalESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Errored Seconds encountered
		 by a SONET/SDH Line in a
		 particular 15-minute interval
		 in the past 24 hours."
	       ::= { sonetLineIntervalEntry 2 }

	  sonetLineIntervalSESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "The counter associated with the number of
		 Severely Errored Seconds
		 encountered by a SONET/SDH Line in a
		 particular 15-minute interval
		 in the past 24 hours."
		::= { sonetLineIntervalEntry 3 }

	  sonetLineIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		"The counter associated with the number of Coding
		Violations encountered by a
		SONET/SDH Line in a
		particular 15-minute interval
		in the past 24 hours."





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	      ::= { sonetLineIntervalEntry 4 }

	  sonetLineIntervalUASs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		"The counter associated with the
		number of Unavailable Seconds
		encountered by a SONET/SDH Line in
		a particular 15-minute interval
		in the past 24 hours."
	      ::= { sonetLineIntervalEntry 5 }

	  sonetLineIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetLineIntervalEntry 6 }




























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	  -- The SONET/SDH Far End Line group.
	  -- This group may only be implemented by SONET/SDH (LTEs)
	  -- systems that provide for a far end block error (FEBE)
	  -- information at the SONET/SDH Line Layer.

	  -- This group consists of two tables:
	  --    SONET/SDH Far End Line Current Table
	  --    SONET/SDH Far End Line Interval Table



	  -- The SONET/SDH Far End Line Current Table

	  -- The SONET/SDH Far End Line Current table contains
	  -- various statistics being
	  -- collected for the current 15 minute interval.
	  -- The statistics are collected from the far end
	  -- block error code (FEBE)
	  -- within the third Z2 byte of the Line Overhead
	  -- in Broadband ISDN applications.
	  -- The definitions are the same as described for
	  -- the near-end information.

	  sonetFarEndLineCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetFarEndLineCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		"The SONET/SDH Far End Line Current table."
	      ::= { sonetFarEndLine 1 }

	  sonetFarEndLineCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetFarEndLineCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		"An entry in the SONET/SDH Far End Line Current table."
	      INDEX   { ifIndex }
	      ::= { sonetFarEndLineCurrentTable 1 }

	  SonetFarEndLineCurrentEntry ::=
	      SEQUENCE {
		  sonetFarEndLineCurrentESs       PerfCurrentCount,
		  sonetFarEndLineCurrentSESs      PerfCurrentCount,
		  sonetFarEndLineCurrentCVs       PerfCurrentCount,





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		  sonetFarEndLineCurrentUASs      PerfCurrentCount
		 }

	  sonetFarEndLineCurrentESs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of Far
		 End Errored Seconds encountered by a SONET/SDH
		 interface in the current 15 minute interval."
	     ::= { sonetFarEndLineCurrentEntry 1 }

	  sonetFarEndLineCurrentSESs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Severely Errored Seconds
		 encountered by a SONET/SDH Medium/Section/Line
		 interface in the current 15 minute
		 interval."
	     ::= { sonetFarEndLineCurrentEntry 2 }

	  sonetFarEndLineCurrentCVs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Coding Violations reported via
		 the far end block error count
		 encountered by a
		 SONET/SDH Medium/Section/Line
		 interface in the current 15 minute interval."
	     ::= { sonetFarEndLineCurrentEntry 3 }

	  sonetFarEndLineCurrentUASs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Unavailable Seconds





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		 encountered by a
		 SONET/SDH Medium/Section/Line
		 interface in the current 15 minute interval."
	     ::= { sonetFarEndLineCurrentEntry 4 }














































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	  -- The SONET/SDH Far End Line Interval Table

	  -- The SONET/SDH Far End Line Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetFarEndLineIntervalTable OBJECT-TYPE
	     SYNTAX  SEQUENCE OF SonetFarEndLineIntervalEntry
	     MAX-ACCESS  not-accessible
	     STATUS  current
	     DESCRIPTION
		"The SONET/SDH Far End Line Interval table."
	     ::= { sonetFarEndLine 2 }

	  sonetFarEndLineIntervalEntry OBJECT-TYPE
	     SYNTAX  SonetFarEndLineIntervalEntry
	     MAX-ACCESS  not-accessible
	     STATUS  current
	     DESCRIPTION
	       "An entry in the SONET/SDH Far
	       End Line Interval table."
	     INDEX   { ifIndex,
		       sonetFarEndLineIntervalNumber }
	     ::= { sonetFarEndLineIntervalTable 1 }

	  SonetFarEndLineIntervalEntry ::=
	      SEQUENCE {
		   sonetFarEndLineIntervalNumber    Integer32,
		   sonetFarEndLineIntervalESs       PerfIntervalCount,
		   sonetFarEndLineIntervalSESs      PerfIntervalCount,
		   sonetFarEndLineIntervalCVs       PerfIntervalCount,
		   sonetFarEndLineIntervalUASs      PerfIntervalCount,
		   sonetFarEndLineIntervalValidData TruthValue
	      }


	  sonetFarEndLineIntervalNumber OBJECT-TYPE
	     SYNTAX  Integer32 (1..96)
	     MAX-ACCESS  not-accessible





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	     STATUS  current
	     DESCRIPTION
		   "A number between 1 and 96, which identifies the
		   interval for which the set of statistics is available.
		   The interval identified by 1 is the most recently
		   completed 15 minute interval,
		   and the interval identified
		   by N is the interval immediately preceding the
		   one identified
		   by N-1."
	     ::= { sonetFarEndLineIntervalEntry 1 }

	  sonetFarEndLineIntervalESs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		  "The counter associated with the number of
		  Far End Errored Seconds encountered
		  by a SONET/SDH Line
		  interface in a particular 15-minute interval
		  in the past 24 hours."
	    ::= { sonetFarEndLineIntervalEntry 2 }

	  sonetFarEndLineIntervalSESs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		  "The counter associated with the number of
		  Far End Severely Errored Seconds
		  encountered by a SONET/SDH Line
		  interface in a particular 15-minute interval
		  in the past 24 hours."
	    ::= { sonetFarEndLineIntervalEntry 3 }

	  sonetFarEndLineIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of
		   Far End Coding Violations reported via
		   the far end block error count
		   encountered by a





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		   SONET/SDH Line
		   interface in a particular 15-minute interval
		   in the past 24 hours."
	      ::= { sonetFarEndLineIntervalEntry 4 }

	  sonetFarEndLineIntervalUASs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Unavailable Seconds
		 encountered by a
		 SONET/SDH Line
		 interface in a particular 15-minute interval
		 in the past 24 hours."
	     ::= { sonetFarEndLineIntervalEntry 5 }

	  sonetFarEndLineIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetFarEndLineIntervalEntry 6 }
























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	  -- the SONET/SDH Path group

	  -- this group consists of 2 tables:
	  -- - the SONET/SDH Path Current Table
	  -- - the SONET/SDH Path Interval Table


	  -- the SONET/SDH Path Current Table

	  -- The SONET/SDH Path
	  -- current table contains various statistics
	  -- being collected for the current 15 minute interval.

	  sonetPathCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetPathCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "The SONET/SDH Path Current table."
	  ::= { sonetPath 1 }

	  sonetPathCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetPathCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "An entry in the SONET/SDH Path Current table."
	      INDEX   { ifIndex }
	  ::= { sonetPathCurrentTable 1 }

	  SonetPathCurrentEntry ::=
	      SEQUENCE {
		  sonetPathCurrentWidth      INTEGER,
		  sonetPathCurrentStatus     Integer32,
		  sonetPathCurrentESs        PerfCurrentCount,
		  sonetPathCurrentSESs       PerfCurrentCount,
		  sonetPathCurrentCVs        PerfCurrentCount,
		  sonetPathCurrentUASs       PerfCurrentCount
	      }


	  sonetPathCurrentWidth OBJECT-TYPE
	      SYNTAX  INTEGER  {
		      sts1(1),
		      sts3cSTM1(2),





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		      sts12cSTM4(3),
		      sts24c(4),
		      sts48cSTM16(5)
	       }
	      MAX-ACCESS  read-write
	      STATUS  current
	      DESCRIPTION
	       "A value that indicates the type of the SONET/SDH
	       Path.  For SONET, the assigned types are
	       the STS-Nc SPEs, where N = 1, 3, 12, 24, and 48.
	       STS-1 is equal to 51.84 Mbps.  For SDH, the assigned
	       types are the STM-Nc VCs, where N = 1, 4, and 16."
	  ::= { sonetPathCurrentEntry 1 }

	  sonetPathCurrentStatus OBJECT-TYPE
	      SYNTAX  Integer32 (1..62)
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		"This variable indicates the
		status of the interface.
		The sonetPathCurrentStatus
		is a bit map represented
		as a sum, therefore,
		it can represent multiple defects
		simultaneously.
		The sonetPathNoDefect should be
		set if and only if
		no other flag is set.

		The various bit positions are:
		   1   sonetPathNoDefect
		   2   sonetPathSTSLOP
		   4   sonetPathSTSAIS
		   8   sonetPathSTSRDI
		  16   sonetPathUnequipped
		  32   sonetPathSignalLabelMismatch"
	  ::= { sonetPathCurrentEntry 2 }

	  sonetPathCurrentESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Errored





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	       Seconds encountered by a SONET/SDH
	       Path in the current 15 minute interval."
	  ::= { sonetPathCurrentEntry 3 }

	  sonetPathCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Severely Errored Seconds
	       encountered by a SONET/SDH Path in the current 15
	       minute
	       interval."
	  ::= { sonetPathCurrentEntry 4 }

	  sonetPathCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Coding
	       Violations encountered by a
	       SONET/SDH Path in the current 15 minute interval."
	  ::= { sonetPathCurrentEntry 5 }

	  sonetPathCurrentUASs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Unavailable Seconds
	       encountered by a Path in the current
	       15 minute interval."
	  ::= { sonetPathCurrentEntry 6 }














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	  -- the SONET/SDH Path Interval Table

	  -- The SONET/SDH Path Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetPathIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetPathIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "The SONET/SDH Path Interval table."
	  ::= { sonetPath 2 }

	  sonetPathIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetPathIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "An entry in the SONET/SDH Path Interval table."
	      INDEX   { ifIndex,
			sonetPathIntervalNumber }
	  ::= { sonetPathIntervalTable 1 }


	  SonetPathIntervalEntry ::=
	      SEQUENCE {
		   sonetPathIntervalNumber     Integer32,
		   sonetPathIntervalESs        PerfIntervalCount,
		   sonetPathIntervalSESs       PerfIntervalCount,
		   sonetPathIntervalCVs        PerfIntervalCount,
		   sonetPathIntervalUASs       PerfIntervalCount,
		   sonetPathIntervalValidData  TruthValue
	      }


	  sonetPathIntervalNumber OBJECT-TYPE
	      SYNTAX  Integer32 (1..96)
	      MAX-ACCESS  not-accessible





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	      STATUS  current
	      DESCRIPTION
		 "A number between 1 and 96, which identifies the
		 interval for which the set of statistics is available.
		 The interval identified by 1 is the most recently
		 completed 15 minute interval,
		 and the interval identified
		 by N is the interval immediately preceding the
		 one identified
		 by N-1."
	  ::= { sonetPathIntervalEntry 1 }

	  sonetPathIntervalESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Errored Seconds encountered
	       by a SONET/SDH Path in a
	       particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetPathIntervalEntry 2 }

	  sonetPathIntervalSESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Severely Errored Seconds
	       encountered by a SONET/SDH Path in
	       a particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetPathIntervalEntry 3 }

	  sonetPathIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Coding
	       Violations encountered by a
	       SONET/SDH Path in a particular 15-minute interval
	       in the past 24 hours."





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	  ::= { sonetPathIntervalEntry 4 }

	  sonetPathIntervalUASs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Unavailable Seconds
	       encountered by a Path in a
	       particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetPathIntervalEntry 5 }

	  sonetPathIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetPathIntervalEntry 6 }




























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	  -- The SONET/SDH Far End Path group

	  -- This group consists of two tables:
	  --  - SONET/SDH Far End Path Current Table
	  --  - SONET/SDH Far End Path Interval Table

	  -- The SONET/SDH Far End Path Current Table

	  -- The SONET/SDH Far End Path Current table
	  -- contains various statistics
	  -- being collected for the current 15 minute interval.
	  -- The statistics are collected from
	  -- the far end block error code
	  -- (FEBE) within the G1 byte of the Path Overhead.
	  -- The definitions are the same as described for
	  -- the near-end information.

	  sonetFarEndPathCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetFarEndPathCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		   "The SONET/SDH Far End Path Current table."
	      ::= { sonetFarEndPath 1 }

	  sonetFarEndPathCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetFarEndPathCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		   "An entry in the SONET/SDH Far End Path Current table."
	      INDEX   { ifIndex }
	      ::= { sonetFarEndPathCurrentTable 1 }

	  SonetFarEndPathCurrentEntry ::=
	      SEQUENCE {
		  sonetFarEndPathCurrentESs       PerfCurrentCount,
		  sonetFarEndPathCurrentSESs      PerfCurrentCount,
		  sonetFarEndPathCurrentCVs       PerfCurrentCount,
		  sonetFarEndPathCurrentUASs      PerfCurrentCount
	      }


	  sonetFarEndPathCurrentESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount





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	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of Far
		   End Errored Seconds encountered by a SONET/SDH
		   interface in the current 15 minute interval."
	      ::= { sonetFarEndPathCurrentEntry 1 }

	  sonetFarEndPathCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of
		   Far End Severely Errored Seconds
		   encountered by a SONET/SDH Path
		   interface in the current 15 minute
		   interval."
	      ::= { sonetFarEndPathCurrentEntry 2 }

	  sonetFarEndPathCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of
		   Far End Coding Violations reported via
		   the far end block error count
		   encountered by a
		   SONET/SDH Path interface in
		   the current 15 minute interval."
	      ::= { sonetFarEndPathCurrentEntry 3 }

	  sonetFarEndPathCurrentUASs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Unavailable Seconds
		 encountered by a
		 SONET/SDH Path interface in
		 the current 15 minute interval."
	     ::= { sonetFarEndPathCurrentEntry 4 }






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	  -- The SONET/SDH Far End Path Interval Table

	  -- The SONET/SDH Far End Path Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetFarEndPathIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetFarEndPathIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		  "The SONET/SDH Far End Path Interval table."
	      ::= { sonetFarEndPath 2 }

	  sonetFarEndPathIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetFarEndPathIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "An entry in the SONET/SDH Far
		 End Path Interval table."
	      INDEX   { ifIndex,
			sonetFarEndPathIntervalNumber }
	      ::= { sonetFarEndPathIntervalTable 1 }

	  SonetFarEndPathIntervalEntry ::=
	      SEQUENCE {
		   sonetFarEndPathIntervalNumber     Integer32,
		   sonetFarEndPathIntervalESs        PerfIntervalCount,
		   sonetFarEndPathIntervalSESs       PerfIntervalCount,
		   sonetFarEndPathIntervalCVs        PerfIntervalCount,
		   sonetFarEndPathIntervalUASs       PerfIntervalCount,
		   sonetFraEndPathIntervalValidData  TruthValue
	      }

	  sonetFarEndPathIntervalNumber OBJECT-TYPE
	     SYNTAX  Integer32 (1..96)
	     MAX-ACCESS  not-accessible
	     STATUS  current





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	     DESCRIPTION
		  "A number between 1 and 96, which identifies the
		  interval for which the set of statistics is available.
		  The interval identified by 1 is the most recently
		  completed 15 minute interval,
		  and the interval identified
		  by N is the interval immediately preceding the
		  one identified
		  by N-1."
	     ::= { sonetFarEndPathIntervalEntry 1 }

	  sonetFarEndPathIntervalESs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		  "The counter associated with the number of
		  Far End Errored Seconds encountered
		  by a SONET/SDH Path interface in a
		  particular 15-minute interval
		  in the past 24 hours."
	     ::= { sonetFarEndPathIntervalEntry 2 }

	  sonetFarEndPathIntervalSESs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		  "The counter associated with the number of
		  Far End Severely Errored Seconds
		  encountered by a SONET/SDH Path interface
		  in a particular 15-minute interval
		  in the past 24 hours."
	     ::= { sonetFarEndPathIntervalEntry 3 }

	  sonetFarEndPathIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of
		   Far End Coding Violations reported via
		   the far end block error count
		   encountered by a
		   SONET/SDH Path interface





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		   in a particular 15-minute interval
		   in the past 24 hours."
	      ::= { sonetFarEndPathIntervalEntry 4 }

	  sonetFarEndPathIntervalUASs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Unavailable Seconds
		 encountered by a
		 SONET/SDH Path interface in
		 a particular 15-minute interval
		 in the past 24 hours."
	     ::= { sonetFarEndPathIntervalEntry 5 }

	  sonetFarEndPathIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetFarEndPathIntervalEntry 6 }

























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	  -- the SONET/SDH Virtual Tributary group

	  -- this group consists of 2 tables:
	  -- - the SONET/SDH VT Current Table
	  -- - the SONET/SDH VT Interval Table

	  -- For SDH signals, virtual tributaries are
	  -- called VCs instead of VTs

	  -- A VT1.5 = VC11
	  -- A VT2 = VC12
	  -- A VT3 = none
	  -- A VT6 = VC3


	  -- the SONET/SDH VT Current Table

	  -- The SONET/SDH VT current table
	  -- contains various statistics
	  -- being collected for the
	  -- current 15 minute interval.

	  sonetVTCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetVTCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "The SONET/SDH VT Current table."
	  ::= { sonetVT 1 }

	  sonetVTCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetVTCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "An entry in the SONET/SDH VT Current table."
	      INDEX   { ifIndex }
	  ::= { sonetVTCurrentTable 1 }

	  SonetVTCurrentEntry ::=
	      SEQUENCE {
		  sonetVTCurrentWidth      INTEGER,
		  sonetVTCurrentStatus     Integer32,
		  sonetVTCurrentESs        PerfCurrentCount,
		  sonetVTCurrentSESs       PerfCurrentCount,





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		  sonetVTCurrentCVs        PerfCurrentCount,
		  sonetVTCurrentUASs       PerfCurrentCount
	      }

	  sonetVTCurrentWidth OBJECT-TYPE
	      SYNTAX  INTEGER {
		      vtWidth15VC11(1),
		      vtWidth2VC12(2),
		      vtWidth3(3),
		      vtWidth6VC2(4),
		      vtWidth6c(5)
		   }
	      MAX-ACCESS  read-write
	      STATUS  current
	      DESCRIPTION
	      "A value that indicates the type of the SONET
	       VT and SDH VC.  Assigned widths are
	       VT1.5/VC11, VT2/VC12, VT3, VT6/VC2, and VT6c."
	  ::= { sonetVTCurrentEntry 1 }

	  sonetVTCurrentStatus OBJECT-TYPE
	      SYNTAX  Integer32 (1..126)
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		"This variable indicates the
		status of the interface.
		The sonetVTCurrentStatus
		is a bit map represented
		as a sum, therefore,
		it can represent multiple defects
		and failures
		simultaneously.
		The sonetVTNoDefect should be
		set if and only if
		no other flag is set.

		The various bit positions are:
		   1   sonetVTNoDefect
		   2   sonetVTLOP
		   4   sonetVTPathAIS
		   8   sonetVTPathRDI
		  16   sonetVTPathRFI
		  32   sonetVTUnequipped
		  64   sonetVTSignalLabelMismatch"





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	  ::= { sonetVTCurrentEntry 2 }

	  sonetVTCurrentESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Errored
	       Seconds encountered by a SONET/SDH
	       VT in the current 15 minute interval."
	  ::= { sonetVTCurrentEntry 3 }

	  sonetVTCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Severely Errored Seconds
	       encountered by a SONET/SDH VT in the current 15 minute
	       interval."
	  ::= { sonetVTCurrentEntry 4 }

	  sonetVTCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Coding
	       Violations encountered by a
	       SONET/SDH VT in the current 15 minute interval."
	  ::= { sonetVTCurrentEntry 5 }

	  sonetVTCurrentUASs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Unavailable Seconds
	       encountered by a VT in the current
	       15 minute interval."
	  ::= { sonetVTCurrentEntry 6 }







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	  -- the SONET/SDH VT Interval Table

	  -- The SONET/SDH VT Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetVTIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetVTIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "The SONET/SDH VT Interval table."
	  ::= { sonetVT 2 }

	  sonetVTIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetVTIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
	       "An entry in the SONET/SDH VT Interval table."
	      INDEX   { ifIndex,
			sonetVTIntervalNumber }
	  ::= { sonetVTIntervalTable 1 }

	  SonetVTIntervalEntry ::=
	      SEQUENCE {
		  sonetVTIntervalNumber     Integer32,
		  sonetVTIntervalESs        PerfIntervalCount,
		  sonetVTIntervalSESs       PerfIntervalCount,
		  sonetVTIntervalCVs        PerfIntervalCount,
		  sonetVTIntervalUASs       PerfIntervalCount,
		  sonetVTIntervalValidData  TruthValue
	      }

	  sonetVTIntervalNumber OBJECT-TYPE
	      SYNTAX  Integer32 (1..96)
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION





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		"A number between 1 and 96, which identifies the
		interval for which the set of statistics is available.
		The interval identified by 1 is the most recently
		completed 15 minute interval,
		and the interval identified
		by N is the interval immediately preceding the
		one identified
		by N-1."
	  ::= { sonetVTIntervalEntry 1 }

	  sonetVTIntervalESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Errored Seconds encountered
	       by a SONET/SDH VT in a particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetVTIntervalEntry 2 }

	  sonetVTIntervalSESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Severely Errored Seconds
	       encountered by a SONET/SDH VT
	       in a particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetVTIntervalEntry 3 }

	  sonetVTIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of Coding
	       Violations encountered by a
	       SONET/SDH VT in a particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetVTIntervalEntry 4 }

	  sonetVTIntervalUASs OBJECT-TYPE





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	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
	       "The counter associated with the number of
	       Unavailable Seconds
	       encountered by a VT in a particular 15-minute interval
	       in the past 24 hours."
	  ::= { sonetVTIntervalEntry 5 }

	  sonetVTIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetVTIntervalEntry 6 }
































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	  -- The SONET/SDH Far End VT group

	  -- This group consists of two tables:
	  --    SONET/SDH Far End VT Current Table
	  --    SONET/SDH Far End VT Interval Table


	  -- The SONET/SDH Far End VT Current

	  -- The SONET/SDH Far End VT Current table
	  -- contains various statistics
	  -- being collected for the current 15 minute interval.
	  -- The statistics are collected from
	  -- the far end block error code
	  -- (FEBE) within the G1 byte of the VT Overhead.
	  -- The definitions are the same as described for
	  -- the near-end information.

	  sonetFarEndVTCurrentTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetFarEndVTCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		  "The SONET/SDH Far End VT Current table."
	      ::= { sonetFarEndVT 1 }

	  sonetFarEndVTCurrentEntry OBJECT-TYPE
	      SYNTAX  SonetFarEndVTCurrentEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		  "An entry in the SONET/SDH Far End VT Current table."
	      INDEX   { ifIndex }
	      ::= { sonetFarEndVTCurrentTable 1 }

	  SonetFarEndVTCurrentEntry ::=
	      SEQUENCE {
		  sonetFarEndVTCurrentESs       PerfCurrentCount,
		  sonetFarEndVTCurrentSESs      PerfCurrentCount,
		  sonetFarEndVTCurrentCVs       PerfCurrentCount,
		  sonetFarEndVTCurrentUASs      PerfCurrentCount
	      }


	  sonetFarEndVTCurrentESs OBJECT-TYPE





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	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		  "The counter associated with the number of Far
		  End Errored Seconds encountered by a SONET/SDH
		  interface in the current 15 minute interval."
	  ::= { sonetFarEndVTCurrentEntry 1 }

	  sonetFarEndVTCurrentSESs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		  "The counter associated with the number of
		  Far End Severely Errored Seconds
		  encountered by a SONET/SDH VT interface
		  in the current 15 minute
		  interval."
	      ::= { sonetFarEndVTCurrentEntry 2 }

	  sonetFarEndVTCurrentCVs OBJECT-TYPE
	      SYNTAX  PerfCurrentCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		  "The counter associated with the number of
		  Far End Coding Violations reported via
		  the far end block error count
		  encountered by a
		  SONET/SDH VT interface
		  in the current 15 minute interval."
	      ::= { sonetFarEndVTCurrentEntry 3 }

	  sonetFarEndVTCurrentUASs OBJECT-TYPE
	     SYNTAX  PerfCurrentCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		"The counter associated with the number of
		Far End Unavailable Seconds
		encountered by a
		SONET/SDH VT interface
		in the current 15 minute interval."
	     ::= { sonetFarEndVTCurrentEntry 4 }





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	  -- The SONET/SDH Far End VT Interval Table

	  -- The SONET/SDH Far End VT Interval Table
	  -- contains various statistics
	  -- collected by each system over a maximum
	  -- of the previous 24 hours of
	  -- operation.  The past 24 hours may be broken into 96
	  -- completed 15 minute intervals.
	  -- A system is required to store at
	  -- least 4 completed 15 minute interval.
	  -- The default value is 32 intervals.

	  sonetFarEndVTIntervalTable OBJECT-TYPE
	      SYNTAX  SEQUENCE OF SonetFarEndVTIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		 "The SONET/SDH Far End VT Interval table."
	      ::= { sonetFarEndVT 2 }

	  sonetFarEndVTIntervalEntry OBJECT-TYPE
	      SYNTAX  SonetFarEndVTIntervalEntry
	      MAX-ACCESS  not-accessible
	      STATUS  current
	      DESCRIPTION
		"An entry in the SONET/SDH Far
		End VT Interval table."
	      INDEX   { ifIndex,
			sonetFarEndVTIntervalNumber }
	      ::= { sonetFarEndVTIntervalTable 1 }

	  SonetFarEndVTIntervalEntry ::=
	     SEQUENCE {
		   sonetFarEndVTIntervalNumber     Integer32,
		   sonetFarEndVTIntervalESs        PerfIntervalCount,
		   sonetFarEndVTIntervalSESs       PerfIntervalCount,
		   sonetFarEndVTIntervalCVs        PerfIntervalCount,
		   sonetFarEndVTIntervalUASs       PerfIntervalCount,
		   sonetFarEndVTIntervalValidData  TruthValue
	      }

	  sonetFarEndVTIntervalNumber OBJECT-TYPE
	      SYNTAX  Integer32 (1..96)
	      MAX-ACCESS  not-accessible
	      STATUS  current





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	      DESCRIPTION
		 "A number between 1 and 96, which identifies the
		 interval for which the set of statistics is available.
		 The interval identified by 1 is the most recently
		 completed 15 minute interval,
		 and the interval identified
		 by N is the interval immediately preceding the
		 one identified
		 by N-1."
	      ::= { sonetFarEndVTIntervalEntry 1 }

	  sonetFarEndVTIntervalESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		    "The counter associated with the number of
		    Far End Errored Seconds encountered
		    by a SONET/SDH VT interface
		    in a particular 15-minute interval
		    in the past 24 hours."
	     ::= { sonetFarEndVTIntervalEntry 2 }

	  sonetFarEndVTIntervalSESs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		    "The counter associated with the number of
		    Far End Severely Errored Seconds
		    encountered by a SONET/SDH VT interface
		    in a particular 15-minute interval
		    in the past 24 hours."
	      ::= { sonetFarEndVTIntervalEntry 3 }

	  sonetFarEndVTIntervalCVs OBJECT-TYPE
	      SYNTAX  PerfIntervalCount
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		   "The counter associated with the number of
		   Far End Coding Violations reported via
		   the far end block error count
		   encountered by a
		   SONET/SDH VT interface in a





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		   particular 15-minute interval
		   in the past 24 hours."
	      ::= { sonetFarEndVTIntervalEntry 4 }

	  sonetFarEndVTIntervalUASs OBJECT-TYPE
	     SYNTAX  PerfIntervalCount
	     MAX-ACCESS  read-only
	     STATUS  current
	     DESCRIPTION
		 "The counter associated with the number of
		 Far End Unavailable Seconds
		 encountered by a
		 SONET/SDH VT interface in a
		 particular 15-minute interval
		 in the past 24 hours."
	     ::= { sonetFarEndVTIntervalEntry 5 }

	  sonetFarEndVTIntervalValidData OBJECT-TYPE
	      SYNTAX  TruthValue
	      MAX-ACCESS  read-only
	      STATUS  current
	      DESCRIPTION
		 "This variable indicates if there is valid data for
		  this interval."
	      ::= { sonetFarEndVTIntervalEntry 6 }

























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	  -- conformance information

	  sonetConformance OBJECT IDENTIFIER ::= { sonetMIB 4 }

	  sonetGroups      OBJECT IDENTIFIER ::= { sonetConformance 1 }
	  sonetCompliances OBJECT IDENTIFIER ::= { sonetConformance 2 }

	  -- deprecated compliance statement

	  sonetCompliance MODULE-COMPLIANCE
	      STATUS  deprecated
	      DESCRIPTION
		      "The compliance statement for SONET/SDH interfaces."

	      MODULE  -- this module
		  MANDATORY-GROUPS { sonetMediumStuff, sonetSectionStuff }

		  GROUP       sonetLineStuff
		  DESCRIPTION
		      "Implementation of this group is mandatory for all
		       SONET/SDH systems that terminate SONET/SDH Lines,
		       Paths or Virtual Tributaries."

		  GROUP       sonetFarEndLineStuff
		  DESCRIPTION
		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate SONET/SDH Lines,
		       Paths or Virtual Tributaries, and that
		       provide for a far end block error (FEBE)
		       information at the SONET/SDH Line Layer."

		  GROUP       sonetPathStuff
		  DESCRIPTION
		      "Implementation of this group is mandatory for all
		       SONET/SDH systems that terminate SONET/SDH
		       Paths or Virtual
		       Tributaries."

		  OBJECT      sonetPathCurrentWidth
		  MIN-ACCESS  read-only
		  DESCRIPTION
		      "Write access is not required."

		  GROUP       sonetFarEndPathStuff
		  DESCRIPTION





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		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate SONET/SDH
		       Paths or Virtual
		       Tributaries, and that process
		       Far End information."

		  GROUP       sonetVTStuff
		  DESCRIPTION
		      "Implementation of this group is mandatory for all
		       SONET/SDH systems that terminate SONET/SDH Virtual
		       Tributaries."

		  OBJECT      sonetVTCurrentWidth
		  MIN-ACCESS  read-only
		  DESCRIPTION
		      "Write access is not required."

		  GROUP       sonetFarEndVTStuff
		  DESCRIPTION
		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate the SONET/SDH
		       floating Virtual
		       Tributaries, and that process Far End information."

	      ::= { sonetCompliances 1 }


	  -- current compliance statements

	  sonetCompliance2 MODULE-COMPLIANCE
	      STATUS  current
	      DESCRIPTION
		      "The compliance statement for SONET/SDH interfaces."

	      MODULE  -- this module
		  MANDATORY-GROUPS { sonetMediumStuff2, sonetSectionStuff2 }

		  OBJECT      sonetMediumCircuitIdentifier
		  MIN-ACCESS  read-only
		  DESCRIPTION
		      "Write access is not required."

		  OBJECT      sonetMediumLoopbackConfig
		  MIN-ACCESS  read-only
		  DESCRIPTION





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		      "Write access is not required."

		  OBJECT      sonetSESthresholdSet
		  MIN-ACCESS      read-only
		  DESCRIPTION
		    "Write access is not required, and only one
		    of the enumerated values need be supported."

		  GROUP       sonetLineStuff2
		  DESCRIPTION
		      "Implementation of this group is mandatory for all
		       SONET/SDH systems that terminate SONET/SDH Lines,
		       Paths or Virtual Tributaries."

		  GROUP       sonetFarEndLineStuff2
		  DESCRIPTION
		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate SONET/SDH Lines,
		       Paths or Virtual Tributaries, and that
		       provide for a far end block error (FEBE)
		       information at the SONET/SDH Line Layer."

		  GROUP       sonetPathStuff2
		  DESCRIPTION
		      "Implementation of this group is mandatory for all
		       SONET/SDH systems that terminate SONET/SDH
		       Paths or Virtual
		       Tributaries."

		  OBJECT      sonetPathCurrentWidth
		  MIN-ACCESS  read-only
		  DESCRIPTION
		      "Write access is not required."

		  GROUP       sonetFarEndPathStuff2
		  DESCRIPTION
		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate SONET/SDH
		       Paths or Virtual
		       Tributaries, and that process
		       Far End information."

		  GROUP       sonetVTStuff2
		  DESCRIPTION
		      "Implementation of this group is mandatory for all





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		       SONET/SDH systems that terminate SONET/SDH Virtual
		       Tributaries."

		  OBJECT      sonetVTCurrentWidth
		  MIN-ACCESS  read-only
		  DESCRIPTION
		      "Write access is not required."

		  GROUP       sonetFarEndVTStuff2
		  DESCRIPTION
		      "Implementation of this group is optional for all
		       SONET/SDH systems that terminate the SONET/SDH
		       floating Virtual
		       Tributaries, and that process Far End information."

	      ::= { sonetCompliances 2 }

	  -- units of conformance

	  -- deprecated groups

	  sonetMediumStuff    OBJECT-GROUP
	      OBJECTS { sonetMediumType,
			sonetMediumTimeElapsed,
			sonetMediumValidIntervals,
			sonetMediumLineCoding,
			sonetMediumLineType,
			sonetMediumCircuitIdentifier }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing configuration
		      information applicable to all SONET/SDH interfaces."
	      ::= { sonetGroups 1 }

	  sonetSectionStuff    OBJECT-GROUP
	      OBJECTS { sonetSectionCurrentStatus,
			sonetSectionCurrentESs,
			sonetSectionCurrentSESs,
			sonetSectionCurrentSEFSs,
			sonetSectionCurrentCVs,
			sonetSectionIntervalESs,
			sonetSectionIntervalSESs,
			sonetSectionIntervalSEFSs,
			sonetSectionIntervalCVs
	   }





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	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Section interfaces."
	      ::= { sonetGroups 2 }

	  sonetLineStuff    OBJECT-GROUP
	      OBJECTS { sonetLineCurrentStatus,
			sonetLineCurrentESs,
			sonetLineCurrentSESs,
			sonetLineCurrentCVs,
			sonetLineCurrentUASs,
			sonetLineIntervalESs,
			sonetLineIntervalSESs,
			sonetLineIntervalCVs,
			sonetLineIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Line interfaces."
	      ::= { sonetGroups 3 }

	  sonetFarEndLineStuff    OBJECT-GROUP
	      OBJECTS { sonetFarEndLineCurrentESs,
			sonetFarEndLineCurrentSESs,
			sonetFarEndLineCurrentCVs,
			sonetFarEndLineCurrentUASs,
			sonetFarEndLineIntervalESs,
			sonetFarEndLineIntervalSESs,
			sonetFarEndLineIntervalCVs,
			sonetFarEndLineIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Line interfaces,
		      and maintaining Line Far End information."
	      ::= { sonetGroups 4 }

	  sonetPathStuff    OBJECT-GROUP
	      OBJECTS { sonetPathCurrentWidth,
			sonetPathCurrentStatus,
			sonetPathCurrentESs,
			sonetPathCurrentSESs,
			sonetPathCurrentCVs,
			sonetPathCurrentUASs,





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			sonetPathIntervalESs,
			sonetPathIntervalSESs,
			sonetPathIntervalCVs,
			sonetPathIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Path interfaces."
	      ::= { sonetGroups 5 }

	  sonetFarEndPathStuff    OBJECT-GROUP
	      OBJECTS { sonetFarEndPathCurrentESs,
			sonetFarEndPathCurrentSESs,
			sonetFarEndPathCurrentCVs,
			sonetFarEndPathCurrentUASs,
			sonetFarEndPathIntervalESs,
			sonetFarEndPathIntervalSESs,
			sonetFarEndPathIntervalCVs,
			sonetFarEndPathIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Path interfaces,
		      and maintaining Path Far End information."
	      ::= { sonetGroups 6 }

	  sonetVTStuff    OBJECT-GROUP
	      OBJECTS { sonetVTCurrentWidth,
			sonetVTCurrentStatus,
			sonetVTCurrentESs,
			sonetVTCurrentSESs,
			sonetVTCurrentCVs,
			sonetVTCurrentUASs,
			sonetVTIntervalESs,
			sonetVTIntervalSESs,
			sonetVTIntervalCVs,
			sonetVTIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH VT interfaces."
	      ::= { sonetGroups 7 }

	  sonetFarEndVTStuff    OBJECT-GROUP
	      OBJECTS { sonetFarEndVTCurrentESs,





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			sonetFarEndVTCurrentSESs,
			sonetFarEndVTCurrentCVs,
			sonetFarEndVTCurrentUASs,
			sonetFarEndVTIntervalESs,
			sonetFarEndVTIntervalSESs,
			sonetFarEndVTIntervalCVs,
			sonetFarEndVTIntervalUASs }
	      STATUS  deprecated
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH VT interfaces,
		      and maintaining VT Far End information."
	      ::= { sonetGroups 8 }


	  -- current groups

	  sonetMediumStuff2    OBJECT-GROUP
	      OBJECTS { sonetMediumType,
			sonetMediumTimeElapsed,
			sonetMediumValidIntervals,
			sonetMediumLineCoding,
			sonetMediumLineType,
			sonetMediumCircuitIdentifier,
			sonetMediumInvalidIntervals,
			sonetMediumLoopbackConfig,
			sonetSESthresholdSet }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing configuration
		      information applicable to all SONET/SDH interfaces."
	      ::= { sonetGroups 9 }

	  sonetSectionStuff2    OBJECT-GROUP
	      OBJECTS { sonetSectionCurrentStatus,
			sonetSectionCurrentESs,
			sonetSectionCurrentSESs,
			sonetSectionCurrentSEFSs,
			sonetSectionCurrentCVs,
			sonetSectionIntervalESs,
			sonetSectionIntervalSESs,
			sonetSectionIntervalSEFSs,
			sonetSectionIntervalCVs,
			sonetSectionIntervalValidData }
	      STATUS  current





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	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Section interfaces."
	      ::= { sonetGroups 10 }

	  sonetLineStuff2    OBJECT-GROUP
	      OBJECTS { sonetLineCurrentStatus,
			sonetLineCurrentESs,
			sonetLineCurrentSESs,
			sonetLineCurrentCVs,
			sonetLineCurrentUASs,
			sonetLineIntervalESs,
			sonetLineIntervalSESs,
			sonetLineIntervalCVs,
			sonetLineIntervalUASs,
			sonetLineIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Line interfaces."
	      ::= { sonetGroups 11 }

	  sonetPathStuff2    OBJECT-GROUP
	      OBJECTS { sonetPathCurrentWidth,
			sonetPathCurrentStatus,
			sonetPathCurrentESs,
			sonetPathCurrentSESs,
			sonetPathCurrentCVs,
			sonetPathCurrentUASs,
			sonetPathIntervalESs,
			sonetPathIntervalSESs,
			sonetPathIntervalCVs,
			sonetPathIntervalUASs,
			sonetPathIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Path interfaces."
	      ::= { sonetGroups 12 }

	  sonetVTStuff2    OBJECT-GROUP
	      OBJECTS { sonetVTCurrentWidth,
			sonetVTCurrentStatus,
			sonetVTCurrentESs,
			sonetVTCurrentSESs,





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			sonetVTCurrentCVs,
			sonetVTCurrentUASs,
			sonetVTIntervalESs,
			sonetVTIntervalSESs,
			sonetVTIntervalCVs,
			sonetVTIntervalUASs,
			sonetVTIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH VT interfaces."
	      ::= { sonetGroups 13 }

	  sonetFarEndLineStuff2    OBJECT-GROUP
	      OBJECTS { sonetFarEndLineCurrentESs,
			sonetFarEndLineCurrentSESs,
			sonetFarEndLineCurrentCVs,
			sonetFarEndLineCurrentUASs,
			sonetFarEndLineIntervalESs,
			sonetFarEndLineIntervalSESs,
			sonetFarEndLineIntervalCVs,
			sonetFarEndLineIntervalUASs,
			sonetFarEndLineIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Line interfaces,
		      and maintaining Line Far End information."
	      ::= { sonetGroups 14 }

	  sonetFarEndPathStuff2    OBJECT-GROUP
	      OBJECTS { sonetFarEndPathCurrentESs,
			sonetFarEndPathCurrentSESs,
			sonetFarEndPathCurrentCVs,
			sonetFarEndPathCurrentUASs,
			sonetFarEndPathIntervalESs,
			sonetFarEndPathIntervalSESs,
			sonetFarEndPathIntervalCVs,
			sonetFarEndPathIntervalUASs,
			sonetFarEndPathIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH Path interfaces,
		      and maintaining Path Far End information."





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	      ::= { sonetGroups 15 }

	  sonetFarEndVTStuff2    OBJECT-GROUP
	      OBJECTS { sonetFarEndVTCurrentESs,
			sonetFarEndVTCurrentSESs,
			sonetFarEndVTCurrentCVs,
			sonetFarEndVTCurrentUASs,
			sonetFarEndVTIntervalESs,
			sonetFarEndVTIntervalSESs,
			sonetFarEndVTIntervalCVs,
			sonetFarEndVTIntervalUASs,
			sonetFarEndVTIntervalValidData }
	      STATUS  current
	      DESCRIPTION
		      "A collection of objects providing information
		      specific to SONET/SDH VT interfaces,
		      and maintaining VT Far End information."
	      ::= { sonetGroups 16 }


	  END





























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	  7.  Acknowledgments

	  This specification is a product of the AToM MIB Working Group.















































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	  8.  Security Considerations

	  Security issues are not discussed in this memo.















































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	  9.  References

	  [1]  SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.,
	       and S. Waldbusser, "Structure of Management Information
	       for version 2 of the Simple Network Management Protocol
		(SNMPv2)", RFC 1902, January 1996.

	  [2]  SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.,
	       and S. Waldbusser, "Textual Conventions for version 2 of
	       the Simple Network Management Protocol (SNMPv2)", RFC
	       1903, January 1996.

	  [3]  SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.,
	       and S. Waldbusser, "Conformance Statements for Version 2
	       of the Simple Network Management Protocol (SNMPv2)", RFC
	       1904, January 1996.

	  [4]  Case, J., Fedor, M., Schoffstall, M., and J. Davin,
	       "Simple Network Management Protocol", RFC 1157, SNMP
	       Research, Performance Systems International, Performance
	       Systems International, MIT Laboratory for Computer
	       Science, May 1990.

	  [5]  SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.,
	       and S. Waldbusser, "Protocol Operations for version 2 of
	       the Simple Network Management Protocol (SNMPv2)", RFC
	       1905, January 1996.

	  [6]  McCloghrie, K., and M. Rose, "Management Information Base
	       for Network Management of TCP/IP-based internets - MIB-
	       II", RFC 1213, Hughes LAN Systems, Performance Systems
	       International, March 1991.

	  [7]  Information processing systems - Open Systems
	       Interconnection - Specification of Abstract Syntax
	       Notation One (ASN.1), International Organization for
	       Standardization.  International Standard 8824, (December,
	       1987).

	  [8]  Information processing systems - Open Systems
	       Interconnection - Specification of Basic Encoding Rules
	       for Abstract Notation One (ASN.1), International
	       Organization for Standardization.  International Standard
	       8825, (December, 1987).






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	  [9]  American National Standard for Telecommunications -
	       Digital Hierarchy - Optical Interface Rates and Formats
	       Specification, ANSI T1.105-1988.

	  [9a] ANSI T1.105-1991.

	  [10] American National Standard for Telecommunications -
	       Digital Hierarchy - Optical Interface Specification
		(Single-Mode), ANSI T1.106-1988.

	  [11] American National Standard for Telecommunications --
	       Layer 1 In-Service Digital Transmission Performance
	       Monitoring T1.231, September 1993.

	  [12] K. McCloghrie and F. Kastenholz, Evolution of Interfaces
	       Group of MIB-II, Internet Draft, November 29, 1993.

	  [13] Fowler, D., "Definitions of Managed Objects for the
	       DS3/E3 Interface Type", RFCxxxx, Newbridge Networks, ????
	       1996.

	  [14] Fowler, D., "Definitions of Managed Objects for the DS1,
	       E1, DS2 and E2 Interface Types", RFCxxxx, Newbridge
	       Networks, ????? 1996.

	  [15] CCITT Recommendation G.707, "Synchronous Digital
	       Hierarchy Bit Rates", June 1992.

	  [16] CCITT Recommendation G.708, "Network Node Interface for
	       the Synchronous Digital Hierarchy", June 1992.

	  [17] CCITT Recommendation G.709, "Synchronous Multiplexing
	       Structure", June 1992.

	  [18] CCITT Recommendation G.783, "Characteristics of
	       Synchronous Digital Hierarchy (SDH) Multiplexing
	       Equipment Functional Blocks", November 1992.

	  [19] Brown, T., and K. Tesink, "Definitions of Managed Objects
	       for the SONET/SDH Interface Type", RFC1595, Bellcore,
	       March 1994.

	  [20] ANSI T1.231 1993







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	  [21] Bellcore TR-NWT-000253, 1991

	  [22] ITU Recommendation G.826, "Error Performance Parameters
	       and Objectives for International Constant Bit Rate
	       Digital Paths at or above Primary Rate", September 1995
	       (COM 13-R57E).

	  [23] Bellcore GR-253-CORE, Issue 2, Synchronous Optical
	       Network (SONET) Transport SystemsL Common Generic
	       Criteria", December 1995.








































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	  10.  Author's Address


	  Kaj Tesink
	     Bell Communications Research
	     331 Newman Springs Road
	     P.O. Box 7020
	     Red Bank, NJ  07701-7020

	     Phone: (908) 758-5254

	     EMail: kaj@cc.bellcore.com






































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	  Appendix A:  The delay-line approach to statistics collection.

	  According to ANSI T1.231 unavailable time begins at the onset
	  of 10 contiguous severely errored seconds -- that is,
	  unavailable time starts with the first of the 10 contiguous
	  SESs -- and while an interface is deemed unavailable all
	  counters for that interface are frozen except for the UAS
	  count.  Since changes in the signal state lag the data to
	  which they apply by 10 seconds, an implementation which wishes
	  to avoid making retroactive adjustments to the counts must
	  pass the the one-second statistics through a 10-second delay
	  line prior to updating any counters.  That can be done by
	  performing the following steps at the end of each one second
	  interval.

	  i)   Read near/far end line and path CV counts and alarm
	       status flags from the hardware.

	  ii)  Accumulate the CV counts for the preceding second and
	       compare them to the ES and SES threshold for the layer in
	       question.  Update the signal state and shift the one-
	       second CV counts and ES/SES flags into the 10-element
	       delay line.  Note that far-end one-second statistics are
	       to be flagged as "absent" during any second in which
	       there is an incoming defect at the layer in question or
	       at any lower layer.

	  iii) Update the current interval statistics using the signal
	       state from the previous update cycle and the one-second
	       CV counts and ES/SES flags shifted out of the 10-element
	       delay line.

	  This procedure guarantees that the statistical counters will
	  be correctly updated at all times, although they lag real time
	  by 10 seconds.  It is illustrated in the figure below.  At the
	  end of each 15 minutes interval the current interval counts
	  are transferred to the  most recent interval entry and each
	  interval is shifted up by one position, with the oldest being
	  discarded if necessary in order to make room.  The current
	  interval counts then start over from zero.  Note, however,
	  that the signal state calculation does not start anew at each
	  interval boundary;  rather, signal state information is
	  retained across interval boundaries.







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	  +--------------------------------------------------------------+
	  |          READ COUNTERS & STATUS INFO FROM HARDWARE           |
	  |                                                              |
	  |LOS OOF/ SECT  LINE LINE LINE LINE  PATH PATH PATH PATH PATH  |
	  |    LOF   CV    AIS  CV   RDI FEBE   AIS  LOP  CV   RDI  CV   |
	  +--------------------------------------------------------------+
	    |   |     |     |    |    |   |      |    |    |    |    |
	    |   |     |     |    |    |   |      |    |    |    |    |
	    V   V     V     V    V    V   V      V    V    V    V    V
	  +--------------------------------------------------------------+
	  | ACCUM ONE-SEC STATS, CHK ERR THRESHOLDS, & UPDT SIGNAL STATE |
	  |                                                              |
	  |                                                              |
	  |                  NEAR END/FAR END       NEAR END/FAR END     |
	  |SECT SECT SECT  LINE LINE LINE  LINE   PATH PATH PATH  PATH   |
	  |CV   ES   SES    CV   ES   SES AVA/UNA  CV   ES   SES AVA/UNA |
	  +--------------------------------------------------------------+
	    |    |    |      |    |    |     |      |    |    |     |
	    |    |    |      |    |    |     |      |    |    |     |
	    V    V    V      V    V    V     |      V    V    V     |
	  +-------------+  +-------------+   |    +-------------+   |
	  |ONE-SEC DELAY|  |ONE-SEC DELAY|   |    |ONE-SEC DELAY|   |
	  | (1 OF 10)   |  | (1 OF 10)   |   |    | (1 OF 10)   |   |
	  |CV   ES   SES|  |CV   ES   SES|   |    |CV   ES   SES|   |
	  +-------------+  +-------------+   |    +-------------+   |
	    |    |    |      |    |    |     |      |    |    |     |
	    /    /    /      /    /    /     /      /    /    /     /
	    /    /    /      /    /    /     /      /    /    /     /
	    |    |    |      |    |    |     |      |    |    |     |
	    V    V    V      V    V    V     |      V    V    V     |
	  +-------------+  +-------------+   |    +-------------+   |
	  |ONE-SEC DELAY|  |ONE-SEC DELAY|   |    |ONE-SEC DELAY|   |
	  | (10 OF 10)  |  | (10 OF 10)  |   |    | (10 OF 10)  |   |
	  |CV   ES   SES|  |CV   ES   SES|   |    |CV   ES   SES|   |
	  +-------------+  +-------------+   |    +-------------+   |
	    |    |    |      |    |    |     |      |    |    |     |
	    |    |    |      |    |    |     |      |    |    |     |
	    V    V    V      V    V    V     V      V    V    V     V
	  +--------------------------------------------------------------+
	  |              UPDATE STATISTICS COUNTERS                      |
	  |                                                              |
	  |                   NEAR END/FAR END       NEAR END/FAR END    |
	  |   SECTION               LINE                   PATH          |
	  | CV ES EFS SES   CV ES EFS SES AS UAS   CV ES EFS SES AS UAS  |
	  +--------------------------------------------------------------+





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	  Note that if such a procedure is adopted there is no current
	  interval data for the first ten seconds after a system comes
	  up.  noSuchInstance must be returned if a management station
	  attempts to access the current interval counters during this
	  time.

	  It is an implementation-specific matter whether an agent
	  assumes that the initial state of the interface is available
	  or unavailable.









































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	  Appendix B - RFC1595 SES interpretation

	  This appendix contains the values for x for the Section, Line,
	  Path, and VT Layers as used in [11, 19, 21].

			 Value for x for SONET/SDH Section SES Definition

		    Rate            x               Minimum Bit Error Rate
		    =======================================================
		    OC-1             9                      1.5 x 10^-7
		    OC-3            16                        1 x 10^-7
		    OC-9            47                        1 x 10^-7
		    OC-12           63                        1 x 10^-7
		    OC-18           94                        1 x 10^-7
		    OC-24          125                        1 x 10^-7
		    OC-36          187                        1 x 10^-7
		    OC-48          249                        1 x 10^-7


			 Value for x for SONET/SDH Line SES Definition

		    Rate            x               Minimum Bit Error Rate
		    =======================================================
		    OC-1            12                       2 x 10^-7
		    OC-3            32                       2 x 10^-7
		    OC-9            47                       2 x 10^-7
		    OC-12          124                       2 x 10^-7
		    OC-18          186                       2 x 10^-7
		    OC-24          248                       2 x 10^-7
		    OC-36          370                       2 x 10^-7
		    OC-48          494                       2 x 10^-7


			 Value for x for SONET/SDH STS-Path SES Definition

		    Rate            x               Minimum Bit Error Rate
		    =======================================================
		    STS-1            9                       1.5 x 10^-7
		    STS-3           16                         1 x 10^-7











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			 Value for x for SONET/SDH VT-Path SES Definition

		    Rate            x               Minimum Bit Error Rate
		    =======================================================
		    VT1.5            4                       2 x 10^-6
		    VT2              6                       2 x 10^-6
		    VT3              8                       2 x 10^-6
		    VT6             14                       2 x 10^-6










































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	  Table of Contents


	  1 Status of this Memo ...................................    1
	  2 Abstract ..............................................    2
	  3 The SNMP Network Management Framework .................    3
	  4 Objects ...............................................    4
	  4.1 Format of Definitions ...............................    4
	  5 Overview ..............................................    5
	  5.1 Use of the ifTable ..................................    5
	  5.2 Use of ifTable for  SONET/SDH  Medium/Section/Line
	       Layer ..............................................    6
	  5.3 Use of ifTable for SONET/SDH Paths ..................    7
	  5.4 Use of ifTable for SONET/SDH VTs/VCs ................    8
	  5.5 SONET/SDH Terminology ...............................    9
	  6 Object Definitions ....................................   19
	  6.1 The SONET/SDH Medium Group ..........................   21
	  6.2 The SONET/SDH Section Group .........................   26
	  6.2.1 The SONET/SDH Section Current Group ...............   26
	  6.2.2 The SONET/SDH Section Interval Group ..............   29
	  6.3 The SONET/SDH Line Group ............................   32
	  6.3.1 The SONET/SDH Line Current Group ..................   32
	  6.3.2 The SONET/SDH Line Interval Group .................   35
	  6.4 The SONET/SDH Far End Line Group ....................   38
	  6.4.1 The SONET/SDH Far End Line Current Group ..........   38
	  6.4.2 The SONET/SDH Far End Line Interval Group .........   41
	  6.5 The SONET/SDH Path Group ............................   44
	  6.5.1 The SONET/SDH Path Current Group ..................   44
	  6.5.2 The SONET/SDH Path Interval Group .................   47
	  6.6 The SONET/SDH Far End Path Group ....................   50
	  6.6.1 The SONET/SDH Far End Path Current Group ..........   50
	  6.6.2 The SONET/SDH Far End Path Interval Group .........   52
	  6.7 The SONET/SDH Virtual Tributary Group ...............   55
	  6.7.1 The SONET/SDH VT Current Group ....................   55
	  6.7.2 The SONET/SDH VT Interval Group ...................   58
	  6.8 The SONET/SDH Far End VT Group ......................   61
	  6.8.1 The SONET/SDH Far End VT Current Group ............   61
	  6.8.2 The SONET/SDH Far End VT Interval Group ...........   63
	  6.9 Conformance Information .............................   66
	  6.10 Compliance Statements ..............................   66
	  7 Acknowledgments .......................................   76
	  8 Security Considerations ...............................   77
	  9 References ............................................   78
	  10 Author's Address .....................................   81






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