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

Internet Draft                      Lou Berger - Editor (Movaz Networks)
Updates: 3473
Category: Standards Track
Expiration Date: May 2005

                                                           November 2004


               GMPLS - Communication of Alarm Information


                draft-ietf-ccamp-gmpls-alarm-spec-02.txt

Status of this Memo

   By submitting this Internet-Draft, I certify that any applicable
   patent or other IPR claims of which I am aware have been disclosed,
   or will be disclosed, and any of which I become aware will be
   disclosed, in accordance with RFC 3668.

   Internet-Drafts are working documents of the Internet Engineering
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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  ....................   6
 3.1.2  Procedures  ................................................   9
 3.1.3  Error Codes and Values  ....................................  10
 3.1.4  Backwards Compatibility  ...................................  10
 3.2    Controlling Alarm Communication  ...........................  11
 3.2.1  Updated Admin Status Object  ...............................  11
 3.2.2  Procedures  ................................................  11
 3.3    Message Formats  ...........................................  12
 3.4    Relationship to GMPLS UNI  .................................  13
 3.5    Relationship to GMPLS E-NNI   ..............................  14
 4      Security Considerations  ...................................  14
 5      IANA Considerations  .......................................  15
 6      References  ................................................  15
 6.1    Normative References  ......................................  15
 6.2    Informative References  ....................................  16
 7      Contributors  ..............................................  17
 8      Contact Address  ...........................................  17
 9      Full Copyright Statement  ..................................  18
10      Intellectual Property  .....................................  18







Berger, et. al.                                                 [Page 2]

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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.  Additionally, the
   extension described in this document is not intended to replace any
   (existing) data plane fault propagation techniques.

   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.




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



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   messages.

   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   Class = TBA, C-Type = 1
       Reserved.

   o   Class = TBA, C-Type = 2
       Reserved.

   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].










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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.
   The defined TLVs MUST follow any interface identifying TLVs.  No
   rules apply to the relative ordering of the TLVs defined in this
   section.

   [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 as determined
         by the reporting node.  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    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+




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      Reserved: 24 bits

         This field is reserved.  It MUST be set to zero on generation,
         MUST be ignored on receipt and MUST be forwarded unchanged and
         unexamined by transit nodes.

      Impact: 4 bits

         Indicates the impact of the alarm indicated in the TLV.  See
         [M.20] for a general discussion on classification of failures.
         The following values are defined:

          Value       Definition
          -----       ---------------------
            0         Unspecified impact
            1         Non-Service Affecting (Data traffic not interrupted)
            2         Service Affecting (Data traffic is interrupted)

      Severity: 8 bits

         Indicates the impact of the alarm indicated in the TLV.  See
         [RFC3877] for more information on severity.  The following
         values are defined:

          Value       Definition
          -----       ----------
            0         Cleared
            1         Indeterminate
            2         Critical
            3         Major
            4         Minor
            5         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                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+







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                                 [Page 7]

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      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.

   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)      //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+














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      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.  Note
         length includes padding.

      Multiple Error String TLVs may be included in an object.



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.

   Nodes that support the communication of alarm information, SHOULD
   record the information contained in a received ALARM_SPEC 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 effected LSP.  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.  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.

   There are two ways to indicate time.  A global timestamp TLV is used
   to provide an absolute time reference for the occurrence of an alarm.
   The local timestamp TLV is used to provide time reference for the
   occurrence of an alarm that is relative to other information
   advertised by the node.  The global timestamp SHOULD be used on nodes



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   that maintain an absolute time reference.  Both timestamp TLVs MAY be
   used simultaneously.

   Note, ALARM_SPEC objects SHOULD NOT be added to the state of LSPs
   that are in "alarm communication inhibited state."  ALARM_SPEC
   objects MAY be added to the state of LSPs that are in an
   "administratively down" state.  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
   messages 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.


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 [RFC3877].  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.







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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|
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   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 or 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, that is,
   received ALARM_SPEC objects MUST be forwarded unchanged regardless of
   the received or transmitted settings of the I and A-bits.   Note, per
   [RFC3473], the absence of the Admin_Status object is equivalent to
   receiving an object containing values all set to zero (0).




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   I bit related processing behavior MAY be overridden locally based on
   configuration.

   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.  The objects are listed in suggested
   ordering.

   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.

















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   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.

   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 a client-node 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 a client-node 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.





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3.5. Relationship to GMPLS E-NNI

   GMPLS may be used at the external network-to-network (E-NNI)
   interface, see [GMPLS-ENNI].  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-ENNI]. 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 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.



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, or to
   filter or correlate them at domain boundaries.

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









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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, see section 3.1.  The value 197 is suggested.
   The C-type values associated with this object should read "Same
   values as ERROR_SPEC (C-Num 6), with the exception of C-Types 1 and 2
   which are reserved".  The text associated with ALARM_SPEC object
   should also read "The ALARM_SPEC objec
t 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 [RFC3877].
   The suggested Error code value is 28.

   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 begin 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














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Internet Draft  draft-ietf-ccamp-gmpls-alarm-spec-02.txt   November 2004


[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.

[RFC3877]   Chisholm, S., Romascanu, D., "Alarm MIB",
            draft-ietf-disman-alarm-mib-18.txt, September 2004.


6.2. Informative References

[M.20]      ITU-T, "MAINTENANCE  PHILOSOPHY  FOR TELECOMMUNICATION
            NETWORKS", Recommendation M.20, October 1992.
[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-05.txt, October 2004,
            work in progress.

[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-02.txt, July 2004,
             work in progress.

















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Internet Draft  draft-ietf-ccamp-gmpls-alarm-spec-02.txt   November 2004


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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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
   except as set forth therein, the authors retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
   ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
   INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
   INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


10. Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at ietf-
   ipr@ietf.org.













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