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Versions: (draft-berger-ccamp-gmpls-alarm-spec) 00 01 02 03 04 05 06 RFC 4783

Network Working Group               Lou Berger - Editor (Movaz Networks)
Internet Draft
Expiration Date: September 2004

                                                              March 2004


               GMPLS - Communication of Alarm Information


                  draft-ccamp-gmpls-alarm-spec-00.txt

Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026.  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
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   To view the current status of any Internet-Draft, please check the
   "1id-abstracts.txt" listing contained in an Internet-Drafts Shadow
   Directory, see http://www.ietf.org/shadow.html.

Abstract

   This document describes an extension to Generalized MPLS (Multi-
   Protocol Label Switching) signaling to support communication of alarm
   information.  GMPLS signaling already supports the control of alarm
   reporting, but not the communication of alarm information.  This
   document presents both a functional description and GMPLS-RSVP
   specifics of such an extension.  This document also proposes
   modification of the RSVP ERROR_SPEC object.


















Berger, et. al.                                                 [Page 1]

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Contents

 1      Introduction  ..............................................   3
 1.1    Background  ................................................   3
 2      Alarm Information Communication  ...........................   4
 3      GMPLS-RSVP Details  ........................................   5
 3.1    ALARM_SPEC Objects  ........................................   5
 3.1.1  IF_ID ALARM_SPEC (and ERROR_SPEC) TLVs  ....................   5
 3.1.2  Procedures  ................................................   9
 3.1.3  Error Codes and Values  ....................................  10
 3.1.4  Backwards Compatibility  ...................................  10
 3.2    Controlling Alarm Communication  ...........................  10
 3.2.1  Updated Admin Status Object  ...............................  10
 3.2.2  Procedures  ................................................  11
 3.3    Message Formats  ...........................................  11
 3.4    Relationship to GMPLS UNI  .................................  12
 3.5    Relationship to GMPLS E-NNI   ..............................  13
 4      Security Considerations  ...................................  14
 5      IANA Considerations  .......................................  14
 6      References  ................................................  15
 6.1    Normative References  ......................................  15
 6.2    Informative References  ....................................  15
 7      Contributors  ..............................................  16
 8      Contact Address  ...........................................  16
 9      Full Copyright Statement  ..................................  17
10      Intellectual Property  .....................................  17







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1. Introduction

   GMPLS Signaling provides mechanisms that can be used to control the
   reporting of alarms associated with an LSP.  This support is provided
   via Administrative Status Information [RFC3471] and the Admin_Status
   object [RFC3473].  These mechanisms only control if alarm reporting
   is inhibited.  No provision is made for communication of alarm
   information within GMPLS.

   The extension described in this document defines how the alarm
   information associated with a GMPLS label-switched path (LSP) may be
   communicated along the path of the LSP.  Communication both upstream
   and downstream is supported.  The value in communicating such alarm
   information is that this information is then available at every node
   along the LSP for display and diagnostic purposes.  Alarm information
   may also be useful in certain traffic protection scenarios, but such
   uses are out of scope of this document.  Alarm communication is
   supported via a new object, new error/alarm information TLVs, and a
   new Administrative Status Information bit.

   The communication of alarms, as described in this document, is
   controllable on a per LSP basis.  Such communication may be useful
   within network configurations where not all nodes support
   communication to a user for reporting of alarms and/or communication
   is needed to support specific applications.  The support of this
   functionality is optional.

   The communication of alarms within GMPLS does not imply any
   modification in behavior of processing of alarms, or for the
   communication of alarms outside of GMPLS.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].


1.1. Background

   Problems with data plane state can often be detected by associated
   data plane hardware components.  Such data plane problems are
   typically filtered based on elapsed time and local policy.  Problems
   that pass the filtering process are normally raised as alarms.  These
   alarms are available for display to operators.  They also may be
   collected centrally through means that are out of the scope of this
   document.

   Not all data plane problems cause the LSP to be immediately torn
   down.  Further, there may be a desire, particularly in optical



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   transport networks, to retain an LSP and communicate relevant alarm
   information even when the data plane state has failed completely.

   Although error information can be reported using PathErr, ResvErr and
   Notify messages, these messages typically indicate a problem in
   signaling state and can only report one problem at at a time.  This
   makes it hard to correlate all of the problems that may be associated
   with a single LSP and to allow an operator examining the status of an
   LSP to view a full list of current problems.  This situation is
   exacerbated by the absence of any way to communicate that a problem
   has been resolved and a corresponding alarm cleared.

   The extensions defined in this document allow an operator or a
   software component to obtain a full list of current alarms associated
   with all of the resources used to support an LSP.  The extensions
   also ensure that this list is kept up-to-date and synchronized with
   the real alarm status in the network.  Finally, the extensions make
   the list available at every node traversed by an LSP.


2. Alarm Information Communication

   A new object is introduced to carry alarm information details.  The
   details of alarm information are much like the error information
   carried in the existing ERROR_SPEC objects.  For this reason the
   communication of alarm information uses a format that is based on the
   communication of error information.

   The new object introduced to carry alarm information details is
   called an ALARM_SPEC object.  This object has the same format as the
   ERROR_SPEC object, but uses a new C-Num to avoid the semantics of
   error processing.  Also, additional TLVs are defined for the IF_ID
   ALARM_SPEC objects to support the communication of information
   related to a specific alarm.  These TLVs may also be useful when
   included in ERROR_SPEC objects, e.g., when the ERROR_SPEC object is
   carried within a Notify message.

   While the details of alarm information are like the details of
   existing error communication, the semantics of processing differ.
   Alarm information will typically relate to changes in data plane
   state, without changes in control state.  Alarm information will
   always be associated with in-place LSPs.  Such information will also
   typically be most useful to operators and applications other than
   control plane protocol processing.  Finally, while error information
   is communicated within PathErr, ResvErr and Notify messages
   [RFC3473], alarm information will be carried within Path and Resv
   messages.




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   Path messages are used to carry alarm information to downstream nodes
   and Resv messages are used to carry alarm information to upstream
   nodes.  The intent of sending alarm information both upstream and
   downstream is to provide the same visibility to alarm information at
   any point along an LSP.  The communication of multiple alarms
   associated with an LSP is supported.  In this case, multiple
   ALARM_SPEC objects will be carried in the Path or Resv messages.

   The addition of alarm information to Path and Resv messages is
   controlled via a new Administrative Status Information bit.
   Administrative Status Information is carried in the Admin_Status
   object.


3. GMPLS-RSVP Details

   This section provides the GMPLS-RSVP [RFC3473] specification for
   communication of alarm information.  The communication of alarm
   information is optional.  This section applies to nodes that support
   communication of alarm information.


3.1. ALARM_SPEC Objects

   The ALARM_SPEC objects use the same format as the ERROR_SPEC object,
   but with class number of TBA (to be assigned by IANA in the form
   11bbbbbb).

   o   IPv4 ALARM_SPEC object: Class = TBA, C-Type = 1
       Definition same as IPv4 ERROR_SPEC [RFC2205].

   o   IPv6 ALARM_SPEC object: Class = TBA, C-Type = 2
       Definition same as IPv6 ERROR_SPEC [RFC2205].

   o   IPv4 IF_ID ALARM_SPEC object: Class = TBA, C-Type = 3
       Definition same as IPv4 IF_ID ERROR_SPEC [RFC3473].

   o   IPv6 IF_ID ALARM_SPEC object: Class = TBA, C-Type = 4
       Definition same as IPv6 IF_ID ERROR_SPEC [RFC3473].


3.1.1. IF_ID ALARM_SPEC (and ERROR_SPEC) TLVs

   The following new TLVs are defined for use with the IPv4 and IPv6
   IF_ID ALARM_SPEC objects.  They may also be used with the IPv4 and
   IPv6 IF_ID ERROR_SPEC objects.  See [RFC3471] section 9.1.1 for the
   original definition of these values.  Note the length provided below
   is for the total TLV.  All TLVs defined in this section are optional.



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   No rules apply to the relative ordering of these TLVs.  These TLVs
   MUST be listed after any interface identifying TLVs.

   [Note: Type values are TBA (to be assigned) by IANA]

      Type    Length     Description
      ----------------------------------
      512       8        REFERENCE_COUNT
      513       8        SEVERITY
      514       8        GLOBAL_TIMESTAMP
      515       8        LOCAL_TIMESTAMP
      516    variable    ERROR_STRING

   The Reference Count TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Reference Count                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Reference Count: 32 bits

         The number of times this alarm has been repeated.  This field
         MUST NOT be set to zero.

      Only one Reference Count TLV may be included in an object.

   The Severity TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            Reserved                   |Impact |   Severity    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Reserved: 24 bits

         This field is reserved.  It MUST be set to zero on generation
         and MUST be ignored on receipt.







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      Impact: 4 bits

         Indicates the impact of the alarm indicated in the TLV.  The
         following values are defined:

          Value       Definition
          -----       ---------------------
            0         Unspecified impact
            1         Non-Service Affecting
            2         Service Affecting

      Severity: 8 bits

         Indicates the impact of the alarm indicated in the TLV.  The
         following values are defined:

          Value       Definition
          -----       ----------
            0         Reserved
            1         Critical
            2         Major
            3         Minor
            4         Warning

      Only one Severity TLV may be included in an object.

   The Global Timestamp TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Global Timestamp                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Global Timestamp: 32 bits

         The number of seconds since 0000 UT on 1 January 1970,
         according to the clock on the node that originates this TLV.

      Only one Global Timestamp TLV may be included in an object.









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   The Local Timestamp TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Local Timestamp                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Local Timestamp: 32 bits

         Number of seconds reported by the local system clock at the
         time the associated alarm was detected on the node that
         originates this TLV.

      Only one Local Timestamp TLV may be included in an object.


   The Error String TLV has the following format:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              Type             |             Length            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      //          Error String      (NULL padded display string)      //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Error String: 32 bits minimum (variable)

         A string of characters, representing the type of error/alarm.
         This string is padded to the next largest 4 byte boundary using
         null characters.  Null padding is not required when the string
         is 32-bit aligned.  The contents of error string are
         implementation dependent.  See the condition types listed in
         Appendices of [GR833] for a list of example strings.

      Multiple Error String TLVs may be included in an object.










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3.1.2. Procedures

   This section applies to nodes that support the communication of alarm
   information.  ALARM_SPEC objects are carried in Path and Resv
   messages.  Multiple ALARM_SPEC objects MAY be present.  The IPv4 and
   IPv6 formats of the ALARM_SPEC object, C-Type 1 and 2, SHOULD NOT be
   used as they do not support the inclusion of the TLVs defined above.

   Nodes that support the communication of alarm information, SHOULD
   record the information contained in a received ALARM_SPECs for later
   use.  All ALARM_SPEC objects received in Path messages SHOULD be
   passed unmodified downstream in the corresponding Path messages.  All
   ALARM_SPEC objects received in Resv messages SHOULD be passed
   unmodified upstream in the corresponding Resv messages.  ALARM_SPEC
   objects are merged in transmitted Resv messages by including a copy
   of all ALARM_SPEC objects received in corresponding Resv Messages.

   To advertise local alarm information, a node generates an ALARM_SPEC
   object for each alarm and adds it to both the Path and Resv messages
   for the affected LSP.  The IPv4 or IPv6 IF_ID ALARM_SPEC object
   format SHOULD be used.  In all cases, appropriate Error Node Address,
   Error Code and Error Values MUST be set, see below for a discussion
   on Error Code and Error Values.  The InPlace and NotGuilty flags
   SHOULD NOT be set.  When the IPv4 or IPv6 IF_ID ALARM_SPEC object
   format is used, TLVs SHOULD be included to identify the interface, if
   any, the severity, the time and a brief string associated with the
   alarm.  The reference count TLV MAY also be included.  ALARM_SPEC
   objects received from other nodes are not effected by the addition of
   local ALARM_SPEC objects, i.e., they continue to be processed as
   described above.  The choice of which alarm or alarms to advertise
   and which to omit is a local policy matter, and may configurable by
   the user.

   Note, ALARM_SPEC objects SHOULD NOT be added to LSPs that are in
   "alarm communication inhibited."  ALARM_SPEC objects MAY be added to
   LSPs that are "administratively down".  These states are indicated by
   the I and A bits of the Admin_Status object, see Section 3.2.

   To remove local alarm information, a node simply removes the matching
   locally generated ALARM_SPEC objects from the outgoing Path and Resv
   messages.  A node MAY modify a locally generated ALARM_SPEC object.

   Normal refresh and trigger message processing applies to Path or Resv
   message that contain ALARM_SPEC objects.  Note that changes in
   ALARM_SPEC objects from one message to the next may include a
   modification in the contents of a specific ALARM_SPEC object, or a
   change in the number of ALARM_SPEC objects present.  All changes in
   ALARM_SPEC objects SHOULD be processed as trigger messages.



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3.1.3. Error Codes and Values

   The Error Codes and Values used in ALARM_SPEC objects are the same as
   those used in ERROR_SPEC objects.  New Error Code values for use with
   both ERROR_SPEC and ALARM_SPEC objects may be assigned to support
   alarm types defined by other standards.

   In this document we define one new Error Code.  The Error Code uses
   the value TBA (by IANA) and is referred to as "Alarms".  The values
   used in the Error Values field are the same as the values used for
   IANAItuProbableCause in the Alarm MIB [ALARM-MIB].  Note these values
   are managed by IANA, see http://www.iana.org.


3.1.4. Backwards Compatibility

   The support of ALARM_SPEC objects is optional.  Non-supporting nodes
   will pass the objects through the node unmodified, because the
   ALARM_SPEC object has a C-Num of the form 11bbbbbb.

   This allows alarm information to be collected and examined in a
   network built from a collection of nodes some of which support the
   communication of alarm information, and some of which do not.


3.2. Controlling Alarm Communication

   Alarm information communication is controlled via Administrative
   Status Information as carried in the Admin_Status object.  A new bit
   is defined, called the I bit, that indicates when alarm communication
   is to be inhibited.  The definition of this bit does not modify the
   procedures defined in Section 7 of [RFC3473].


3.2.1. Updated Admin Status Object


   The format of the Admin_Status object is updated to include the I
   bit:

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            Length             | Class-Num(196)|   C-Type (1)  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |R|                        Reserved                   |I| |T|A|D|
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




Berger, et. al.                                                [Page 10]

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   Inhibit Alarm Communication (I): 1 bit
         When set, indicates that alarm communication is disabled for
         the LSP and that nodes SHOULD NOT add local alarm information.

      See [RFC3471] for the definition of the remaining bits.


3.2.2. Procedures

   The I bit may be set and cleared using the procedures defined in
   Sections 7.2 and 7.3 of [RFC3473].  A node that receives (or
   generates) an Admin_Status object with the A and I bits set (1),
   SHOULD remove all locally generated alarm information from the
   matching LSP's outgoing Path and Resv messages.  When a node receives
   (or generates) an Admin_Status object with the A and I bits clear
   (0), it should add any local alarm information to the matching LSP's
   outgoing Path and Resv messages.  The processing of non-locally
   generated ALARM_SPEC objects MUST NOT be impacted by the contents of
   the Admin_Status object.  Note, per [RFC3473], the absence of the
   Admin_Status object is equivalent to receiving an object containing
   values all set to zero (0).

   When generating Notify messages for LSPs with the I bit set, the TLVs
   described in this document MAY be added to the ERROR_SPEC object sent
   in the the Notify message.


3.3. Message Formats

   This section presents the RSVP message related formats as modified by
   this document.  The formats specified in [RFC3473] served as the
   basis of these formats.



















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   The format of a Path message is as follows:

   <Path Message> ::=       <Common Header> [ <INTEGRITY> ]
                            [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
                            [ <MESSAGE_ID> ]
                            <SESSION> <RSVP_HOP>
                            <TIME_VALUES>
                            [ <EXPLICIT_ROUTE> ]
                            <LABEL_REQUEST>
                            [ <PROTECTION> ]
                            [ <LABEL_SET> ... ]
                            [ <SESSION_ATTRIBUTE> ]
                            [ <NOTIFY_REQUEST> ]
                            [ <ADMIN_STATUS> ]
                            [ <POLICY_DATA> ... ]
                            [ <ALARM_SPEC> ... ]
                            <sender descriptor>

   <sender descriptor> is not modified by this document.

   The format of a Resv message is as follows:

   <Resv Message> ::=       <Common Header> [ <INTEGRITY> ]
                            [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
                            [ <MESSAGE_ID> ]
                            <SESSION> <RSVP_HOP>
                            <TIME_VALUES>
                            [ <RESV_CONFIRM> ]  [ <SCOPE> ]
                            [ <NOTIFY_REQUEST> ]
                            [ <ADMIN_STATUS> ]
                            [ <POLICY_DATA> ... ]
                            [ <ALARM_SPEC> ... ]
                            <STYLE> <flow descriptor list>

   <flow descriptor list> is not modified by this document.


3.4. Relationship to GMPLS UNI

   [GMPLS-UNI] defines how GMPLS may be used in an overlay model to
   provide a user-to-network interface. In this model, restrictions may
   be applied to the information that is signaled between an edge-node
   and a core-node. This restriction allows the core network to limit
   the information that is visible outside of the core. This restriction
   may be made for confidentiality, privacy or security reasons. It may
   also be made for operational reasons, for example if the information
   is only applicable within the core network.




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   The extensions described in this document are candidates for
   filtering as described in [GMPLS-UNI]. In particular the following
   observations apply.

   o  An ingress or egress core-node MAY filter alarms from the GMPLS core
      to the overlay UNI LSP.  This may be to protect information about the
      core network, or to indicate that the core network is performing or
      has completed recovery actions for the GMPLS LSP.

   o  An ingress or egress core-node MAY modify alarms from the GMPLS
      core when sending to the overlay UNI LSP.  This may facilitate the
      UNI client's ability to understand the failure and its effect on the
      data plane, and enable the UNI client to take corrective actions in a
      more-appropriate manner.

   o  Similarly, an egress core-node MAY choose to not request alarm
      reporting on Path messages that it sends downstream to the overlay
      network.

   o  Further, even when alarm reporting is requested along the whole
      length of an overlay LSP, an ingress or egress core-node MAY choose
      to selectively filter alarms that are reported to the overlay
      network. This may be to protect information about the core network,
      or may reflect the fact that the core network intends to take
      remedial action and does not want the overlay network to operate on
      the alarm information.


3.5. Relationship to GMPLS E-NNI

   GMPLS may be used at the external network-to-network (E-NNI)
   interface, see [GMPLS-ASON].  At this interface, restrictions may be
   applied to the information that is signaled between an egress and an
   ingress core- node.

   This restriction allows the ingress core network to limit the
   information that is visible outside of its core network. This
   restriction may be made for confidentiality, privacy or security
   reasons.  It may also be made for operational reasons, for example if
   the information is only applicable within the core network.

   The extensions described in this document are candidates for
   filtering as described in [GMPLS-ASON]. In particular the following
   observations apply.

   o  An ingress or egress core-node MAY filter internal core network alarms.
      This may be to protect information about the internal network, or to
      indicate that the core network is performing or has completed recovery



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      actions for this LSP.

   o  An ingress or egress core-node MAY modify internal core network alarms.
      This may facilitate the peering E-NNI (i.e. the egress core-node) to
      understand the failure and its effect on the data plane, and take
      corrective actions in a more-appropriate manner or prolong the
      generated alarms upstream/downstream as appropriated.

   o  Similarly, an egress/ingress core-node MAY choose to not request
      alarm reporting on Path messages that it sends downstream.

   o  Further, even when alarm reporting is requested along the whole
      length of an end-to-end LSP, an egress or an ingress core-node MAY
      choose to selectively filter alarms that are reported through the
      UNI. This may be to protect information about the whole core network,
      or may reflect the fact that the core network intends to take
      remedial action and does not want the overlay network to operate
      on the alarm information.


4. Security Considerations

   Some operators may consider alarm information as sensitive.  To
   support environments where this is the case, implementations SHOULD
   allow the user to disable the generation of ALARM_SPEC objects.

   This document introduces no additional security considerations.  See
   [RFC3473] for relevant security considerations.


5. IANA Considerations

   IANA is requested to administer assignment of new values for
   namespaces defined in this document.  This section uses the
   terminology of BCP 26 "Guidelines for Writing an IANA Considerations
   Section in RFCs" [BCP26].

   This document defines a new RSVP "ALARM_SPEC object" with a Class-Num
   of the form 11bbbbbb.  The value 197 is suggested.  The C-type values
   associated with this object should read "Same values as ERROR_SPEC
   (C-Num 6)".  The text associated with ALARM_SPEC object should also
   read "The ALARM_SPEC object uses the Error Code and Values from the
   ERROR_SPEC object."

   Additionally, Section 3.1.3 defines a new Error Code.  The Error Code
   is "Alarms" and uses Error Values defined in the Alarm MIB [ALARM-
   MIB].  The suggested Error code value is 28.




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   This document also defines the TLVs for use with the IF_ID ERROR_SPEC
   objects defined in [RFC3473].  Please see Section 3.1.1 for a list of
   TLV description and (suggested) type values.

   Note that the type values are not sequential with existing ERROR_SPEC
   object TLV assignments.  This is intentional and is intended to
   provide space for future error TLVs.

   This document also defines the I bit in the Admin Status Object, see
   Section 3.2.1.  This bit field was originally defined in Section 7.1
   of [RFC3473].  We recommend that IANA being managing assignment of
   bits in the Admin Status Object, and that the bits be allocated
   through IETF Consensus actions.


6. References

6.1. Normative References

[RFC3471]   Berger, L., Editor, "Generalized Multi-Protocol
            Label Switching (GMPLS) Signaling Functional
            Description", RFC 3471, January 2003.

[RFC3473]   Berger, L., Editor, "Generalized Multi-Protocol Label
            Switching (GMPLS) Signaling - Resource ReserVation
            Protocol-Traffic Engineering (RSVP-TE) Extensions",
            RFC 3473, January 2003.

[ALARM-MIB] Chisholm, S., Romascanu, D., "Alarm MIB",
            draft-ietf-disman-alarm-mib-18.txt, February 2004


6.2. Informative References

[GR833]     Bellcore, "Network Maintenance: Network Element and
            Transport Surveillance Messages" (GR-833-CORE), Issue 3,
            February 1999.

[RFC2119]   Bradner, S., "Key words for use in RFCs to Indicate
            Requirement Levels," RFC 2119.

[GMPLS-UNI] Swallow, G., Drake, J., Ishimatsu, H., and Rekhter, Y.
            "GMPLS UNI: RSVP Support for the Overlay Model",
            draft-ietf-ccamp-gmpls-overlay-02.txt, October 2003,
            work in progress.






Berger, et. al.                                                [Page 15]

Internet Draft     draft-ccamp-gmpls-alarm-spec-00.txt        March 2004


[GMPLS-ENNI] Papadimitriou, D., Editor,  "Generalized MPLS (GMPLS)
             RSVP-TE Signaling in support of Automatically Switched
             Optical Network (ASON)",
             draft-ietf-ccamp-gmpls-rsvp-te-ason-01.txt, January 2004,
             work in progress.


7. Contributors


   Contributors are listed in alphabetical order:

   Lou Berger                                 Deborah Brungard
   Movaz Networks, Inc.                       AT&T Labs, Room MT D1-3C22
   7926 Jones Branch Drive                    200 Laurel Avenue
   Suite 615
   McLean VA, 22102                           Middletown, NJ 07748, USA
   Phone:  +1 703 847-1801                    Phone:  (732) 420-1573
   Email:  lberger@movaz.com                  Email:  dbrungard@att.com

   Igor Bryskin                               Adrian Farrel
   Movaz Networks, Inc.                       Old Dog Consulting
   7926 Jones Branch Drive
   Suite 615
   McLean VA, 22102                           Phone:  +44 (0) 1978 860944
   Email:  ibryskin@movaz.com                 Email:  adrian@olddog.co.uk

   Dimitri Papadimitriou (Alcatel)            Arun Satyanarayana
   Francis Wellesplein 1                      Movaz Networks, Inc.
   B-2018 Antwerpen, Belgium                  7926 Jones Branch Drive
                                              Suite 615
                                              McLean VA, 22102
   Phone:  +32 3 240-8491                     Phone:  +1 703 847-1785
   Email:  dimitri.papadimitriou@alcatel.be   Email:  aruns@movaz.com

8. Contact Address


   Lou Berger
   Movaz Networks, Inc.
   7926 Jones Branch Drive
   Suite 615
   McLean VA, 22102
   Phone:  +1 703 847-1801
   Email:  lberger@movaz.com






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Internet Draft     draft-ccamp-gmpls-alarm-spec-00.txt        March 2004


9. Full Copyright Statement

   Copyright (C) The Internet Society (2004).  This document is subject
   to the rights, licenses and restrictions contained in BCP 78 and
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   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
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   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


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