Network Working Group                                  L. Berger, Editor
Request for Comments: 3473                                Movaz Networks
Category: Standards Track                                   January 2003


    Generalized Multi-Protocol Label Switching (GMPLS) Signaling
Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extensions

Status of this Memo

  This document specifies an Internet standards track protocol for the
  Internet community, and requests discussion and suggestions for
  improvements.  Please refer to the current edition of the "Internet
  Official Protocol Standards" (STD 1) for the standardization state
  and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2003).  All Rights Reserved.

Abstract

  This document describes extensions to Multi-Protocol Label Switching
  (MPLS) Resource ReserVation Protocol - Traffic Engineering (RSVP-TE)
  signaling required to support Generalized MPLS.  Generalized MPLS
  extends the MPLS control plane to encompass time-division (e.g.,
  Synchronous Optical Network and Synchronous Digital Hierarchy,
  SONET/SDH), wavelength (optical lambdas) and spatial switching (e.g.,
  incoming port or fiber to outgoing port or fiber).  This document
  presents a RSVP-TE specific description of the extensions.  A generic
  functional description can be found in separate documents.

Table of Contents

  1.  Introduction  ..............................................   2
  2.  Label Related Formats   ....................................   3
   2.1  Generalized Label Request Object  ........................   3
   2.2  Bandwidth Encoding  ......................................   4
   2.3  Generalized Label Object  ................................   5
   2.4  Waveband Switching  ......................................   5
   2.5  Suggested Label  .........................................   6
   2.6  Label Set  ...............................................   7
  3.  Bidirectional LSPs  ........................................   8
   3.1  Procedures  ..............................................   9
   3.2  Contention Resolution  ...................................   9
  4.  Notification  ..............................................   9
   4.1  Acceptable Label Set Object  .............................  10
   4.2  Notify Request Objects  ..................................  10



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   4.3  Notify Message  ..........................................  12
   4.4  Removing State with a PathErr message  ...................  14
  5.  Explicit Label Control  ....................................  15
   5.1  Label ERO subobject  .....................................  15
   5.2  Label RRO subobject  .....................................  16
  6.  Protection Object  .........................................  17
   6.1  Procedures  ..............................................  18
  7.  Administrative Status Information  .........................  18
   7.1  Admin Status Object  .....................................  18
   7.2  Path and Resv Message Procedures  ........................  18
   7.3  Notify Message Procedures  ...............................  20
  8.  Control Channel Separation  ................................  21
   8.1  Interface Identification  ................................  21
   8.2  Errored Interface Identification  ........................  23
  9.  Fault Handling  ............................................  25
   9.1  Restart_Cap Object  ......................................  25
   9.2  Processing of Restart_Cap Object  ........................  26
   9.3  Modification to Hello Processing to Support
        State Recovery  ..........................................  26
   9.4  Control Channel Faults  ..................................  27
   9.5  Nodal Faults  ............................................  27
  10. RSVP Message Formats and Handling  .........................  30
   10.1  RSVP Message Formats  ...................................  30
   10.2  Addressing Path and PathTear Messages   .................  32
  11. Acknowledgments  ...........................................  32
  12. Security Considerations  ...................................  33
  13. IANA Considerations  .......................................  34
   13.1  IANA Assignments  .......................................  35
  14. Intellectual Property Considerations  ......................  36
  15. References  ................................................  37
   15.1  Normative References  ...................................  37
   15.2  Informative References  .................................  38
  16. Contributors  ..............................................  38
  17. Editor's Address  ..........................................  41
  18. Full Copyright Statement  ..................................  42

1. Introduction

  Generalized MPLS extends MPLS from supporting packet (PSC) interfaces
  and switching to include support of three new classes of interfaces
  and switching: Time-Division Multiplex (TDM), Lambda Switch (LSC) and
  Fiber-Switch (FSC).  A functional description of the extensions to
  MPLS signaling needed to support the new classes of interfaces and
  switching is provided in [RFC3471].  This document presents RSVP-TE
  specific formats and mechanisms needed to support all four classes of
  interfaces.





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  [RFC3471] should be viewed as a companion document to this document.
  The format of this document parallels [RFC3471].  In addition to the
  other features of Generalized MPLS, this document also defines RSVP-
  TE specific features to support rapid failure notification, see
  Sections 4.2 and 4.3.

  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].

2. Label Related Formats

  This section defines formats for a generalized label request, a
  generalized label, support for waveband switching, suggested label
  and label sets.

2.1. Generalized Label Request Object

  A Path message SHOULD contain as specific an LSP (Label Switched
  Path) Encoding Type as possible to allow the maximum flexibility in
  switching by transit LSRs.  A Generalized Label Request object is set
  by the ingress node, transparently passed by transit nodes, and used
  by the egress node.  The Switching Type field may also be updated
  hop-by-hop.

  The format of a Generalized Label Request object is:

   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 (19)|  C-Type (4)   |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  | LSP Enc. Type |Switching Type |             G-PID             |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of parameters.

2.1.1. Procedures

  A node processing a Path message containing a Generalized Label
  Request must verify that the requested parameters can be satisfied by
  the interface on which the incoming label is to be allocated, the
  node itself, and by the interface on which the traffic will be
  transmitted.  The node may either directly support the LSP or it may
  use a tunnel (FA), i.e., another class of switching.  In either case,
  each parameter must be checked.





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  Note that local node policy dictates when tunnels may be used and
  when they may be created.  Local policy may allow for tunnels to be
  dynamically established or may be solely administratively controlled.
  For more information on tunnels and processing of ER hops when using
  tunnels see [MPLS-HIERARCHY].

  Transit and egress nodes MUST verify that the node itself and, where
  appropriate, that the interface or tunnel on which the traffic will
  be transmitted can support the requested LSP Encoding Type.  If
  encoding cannot be supported, the node MUST generate a PathErr
  message, with a "Routing problem/Unsupported Encoding" indication.

  Nodes MUST verify that the type indicated in the Switching Type
  parameter is supported on the corresponding incoming interface.  If
  the type cannot be supported, the node MUST generate a PathErr
  message with a "Routing problem/Switching Type" indication.

  The G-PID parameter is normally only examined at the egress.  If the
  indicated G-PID cannot be supported then the egress MUST generate a
  PathErr message, with a "Routing problem/Unsupported L3PID"
  indication.  In the case of PSC and when penultimate hop popping
  (PHP) is requested, the penultimate hop also examines the (stored)
  G-PID during the processing of the Resv message.  In this case if the
  G-PID is not supported, then the penultimate hop MUST generate a
  ResvErr message with a "Routing problem/Unacceptable label value"
  indication.  The generated ResvErr message MAY include an Acceptable
  Label Set, see Section 4.1.

  When an error message is not generated, normal processing occurs.  In
  the transit case this will typically result in a Path message being
  propagated.  In the egress case and PHP special case this will
  typically result in a Resv message being generated.

2.2. Bandwidth Encoding

  Bandwidth encodings are carried in the SENDER_TSPEC and FLOWSPEC
  objects.  See [RFC3471] for a definition of values to be used for
  specific signal types.  These values are set in the Peak Data Rate
  field of Int-Serv objects, see [RFC2210].  Other bandwidth/service
  related parameters in the object are ignored and carried
  transparently.










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2.3. Generalized Label Object

  The format of a Generalized Label object is:

   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 (16)|   C-Type (2)  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                             Label                             |
  |                              ...                              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of parameters and encoding of labels.

2.3.1. Procedures

  The Generalized Label travels in the upstream direction in Resv
  messages.

  The presence of both a generalized and normal label object in a Resv
  message is a protocol error and should treated as a malformed message
  by the recipient.


  The recipient of a Resv message containing a Generalized Label
  verifies that the values passed are acceptable.  If the label is
  unacceptable then the recipient MUST generate a ResvErr message with
  a "Routing problem/MPLS label allocation failure" indication.

2.4. Waveband Switching Object

  Waveband switching uses the same format as the generalized label, see
  section 2.2.  Waveband Label uses C-Type (3),

  In the context of waveband switching, the generalized label has the
  following format:














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   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 (16)|   C-Type (3)  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                          Waveband Id                          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                          Start Label                          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                           End Label                           |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of parameters.

2.4.1. Procedures

  The procedures defined in Section 2.3.1 apply to waveband switching.
  This includes generating a ResvErr message with a "Routing
  problem/MPLS label allocation failure" indication if any of the label
  fields are unrecognized or unacceptable.

  Additionally, when a waveband is switched to another waveband, it is
  possible that the wavelengths within the waveband will be mirrored
  about a center frequency.  When this type of switching is employed,
  the start and end label in the waveband label object MUST be flipped
  before forwarding the label object with the new waveband Id.  In this
  manner an egress/ingress LSR which receives a waveband label which
  has these values inverted, knows that it must also invert its egress
  association to pick up the proper wavelengths.

  This operation MUST be performed in both directions when a
  bidirectional waveband tunnel is being established.

2.5. Suggested Label Object

  The format of a Suggested_Label object is identical to a generalized
  label.  It is used in Path messages.  A Suggested_Label object uses
  Class-Number 129 (of form 10bbbbbb) and the C-Type of the label being
  suggested.

  Errors in received Suggested_Label objects MUST be ignored.  This
  includes any received inconsistent or unacceptable values.

  Per [RFC3471], if a downstream node passes a label value that differs
  from the suggested label upstream, the upstream LSR MUST either
  reconfigure itself so that it uses the label specified by the
  downstream node or generate a ResvErr message with a "Routing




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  problem/Unacceptable label value" indication.  Furthermore, an
  ingress node SHOULD NOT transmit data traffic using a suggested label
  until the downstream node passes a corresponding label upstream.

2.6. Label Set Object

  The Label_Set object uses Class-Number 36 (of form 0bbbbbbb) and the
  C-Type of 1.  It is used in Path messages.

  The format of a Label_Set is:

   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 (36)|   C-Type (1)  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |    Action     |      Reserved     |        Label Type         |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                          Subchannel 1                         |
  |                              ...                              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  :                               :                               :
  :                               :                               :
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                          Subchannel N                         |
  |                              ...                              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  Label Type: 14 bits

     Indicates the type and format of the labels carried in the object.
     Values match the C-Type of the appropriate RSVP_LABEL object.
     Only the low order 8 bits are used in this field.

  See [RFC3471] for a description of other parameters.

2.6.1. Procedures

  A Label Set is defined via one or more Label_Set objects.  Specific
  labels/subchannels can be added to or excluded from a Label Set via
  Action zero (0) and one (1) objects respectively.  Ranges of
  labels/subchannels can be added to or excluded from a Label Set via
  Action two (2) and three (3) objects respectively.  When the
  Label_Set objects only list labels/subchannels to exclude, this
  implies that all other labels are acceptable.






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  The absence of any Label_Set objects implies that all labels are
  acceptable.  A Label Set is included when a node wishes to restrict
  the label(s) that may be used downstream.

  On reception of a Path message, the receiving node will restrict its
  choice of labels to one which is in the Label Set.  Nodes capable of
  performing label conversion may also remove the Label Set prior to
  forwarding the Path message.  If the node is unable to pick a label
  from the Label Set or if there is a problem parsing the Label_Set
  objects, then the request is terminated and a PathErr message with a
  "Routing problem/Label Set" indication MUST be generated.  It is a
  local matter if the Label Set is stored for later selection on the
  Resv or if the selection is made immediately for propagation in the
  Resv.

  On reception of a Path message, the Label Set represented in the
  message is compared against the set of available labels at the
  downstream interface and the resulting intersecting Label Set is
  forwarded in a Path message.  When the resulting Label Set is empty,
  the Path must be terminated, and a PathErr message, and a "Routing
  problem/Label Set" indication MUST be generated.  Note that
  intersection is based on the physical labels (actual wavelength/band
  values) which may have different logical values on different links,
  as a result it is the responsibility of the node to map these values
  so that they have a consistent physical meaning, or to drop the
  particular values from the set if no suitable logical label value
  exists.

  When processing a Resv message at an intermediate node, the label
  propagated upstream MUST fall within the Label Set.

  Note, on reception of a Resv message a node that is incapable of
  performing label conversion has no other choice than to use the same
  physical label (wavelength/band) as received in the Resv message.  In
  this case, the use and propagation of a Label Set will significantly
  reduce the chances that this allocation will fail.

3. Bidirectional LSPs

  Bidirectional LSP setup is indicated by the presence of an Upstream
  Label in the Path message.  An Upstream_Label object has the same
  format as the generalized label, see Section 2.3.  The Upstream_Label
  object uses Class-Number 35 (of form 0bbbbbbb) and the C-Type of the
  label being used.







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3.1. Procedures

  The process of establishing a bidirectional LSP follows the
  establishment of a unidirectional LSP with some additions.  To
  support bidirectional LSPs an Upstream_Label object is added to the
  Path message.  The Upstream_Label object MUST indicate a label that
  is valid for forwarding at the time the Path message is sent.

  When a Path message containing an Upstream_Label object is received,
  the receiver first verifies that the upstream label is acceptable.
  If the label is not acceptable, the receiver MUST issue a PathErr
  message with a "Routing problem/Unacceptable label value" indication.
  The generated PathErr message MAY include an Acceptable Label Set,
  see Section 4.1.

  An intermediate node must also allocate a label on the outgoing
  interface and establish internal data paths before filling in an
  outgoing upstream label and propagating the Path message.  If an
  intermediate node is unable to allocate a label or internal
  resources, then it MUST issue a PathErr message with a "Routing
  problem/MPLS label allocation failure" indication.

  Terminator nodes process Path messages as usual, with the exception
  that the upstream label can immediately be used to transport data
  traffic associated with the LSP upstream towards the initiator.

  When a bidirectional LSP is removed, both upstream and downstream
  labels are invalidated and it is no longer valid to send data using
  the associated labels.

3.2. Contention Resolution

  There are two additional contention resolution related considerations
  when controlling bidirectional LSP setup via RSVP-TE.  The first is
  that for the purposes of RSVP contention resolution, the node ID is
  the IP address used in the RSVP_HOP object.  The second is that a
  neighbor's node ID might not be known when sending an initial Path
  message.  When this case occurs, a node should suggest a label chosen
  at random from the available label space.

4. Notification

  This section covers several notification related extensions.  The
  first extension defines the Acceptable Label Set object to support
  Notification on Label Error, per [RFC3471].  The second and third
  extensions enable expedited notification of failures and other events
  to nodes responsible for restoring failed LSPs.  (The second
  extension, the Notify Request object, identifies where event



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  notifications are to be sent.  The third extension, the Notify
  message, provides for general event notification.)  The final
  notification related extension allows for the removal of Path state
  on handling of PathErr messages.

4.1. Acceptable Label Set Object

  Acceptable_Label_Set objects use a Class-Number 130 (of form
  10bbbbbb).  The remaining contents of the object, including C-Type,
  have the identical format as the Label_Set object, see Section 2.6.

  Acceptable_Label_Set objects may be carried in PathErr and ResvErr
  messages.  The procedures for defining an Acceptable Label Set follow
  the procedures for defining a Label Set, see Section 2.6.1.
  Specifically, an Acceptable Label Set is defined via one or more
  Acceptable_Label_Set objects.  Specific labels/subchannels can be
  added to or excluded from an Acceptable Label Set via  Action zero
  (0) and one (1) objects respectively.  Ranges of labels/subchannels
  can be added to or excluded from an Acceptable Label Set via Action
  two (2) and three (3) objects respectively.  When the
  Acceptable_Label_Set objects only list labels/subchannels to exclude,
  this implies that all other labels are acceptable.

  The inclusion of Acceptable_Label_Set objects is optional.  If
  included, the PathErr or ResvErr message SHOULD contain a "Routing
  problem/Unacceptable label value" indication.  The absence of
  Acceptable_Label_Set objects does not have any specific meaning.

4.2. Notify Request Objects

  Notifications may be sent via the Notify message defined below.  The
  Notify Request object is used to request the generation of
  notifications.  Notifications, i.e., the sending of a Notify message,
  may be requested in both the upstream and downstream directions.

4.2.1. Required Information

  The Notify Request Object may be carried in Path or Resv Messages,
  see Section 7.  The Notify_Request Class-Number is 195 (of form
  11bbbbbb).  The format of a Notify Request is:

     o  IPv4 Notify Request Object









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   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 (1) |  C-Type (1)   |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                    IPv4 Notify Node Address                   |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  IPv4 Notify Node Address: 32 bits

     The IP address of the node that should be notified when generating
     an error message.

     o  IPv6 Notify Request Object

   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 (2) |  C-Type (2)   |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  |                    IPv6 Notify Node Address                   |
  |                                                               |
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  IPv6 Notify Node Address: 16 bytes

     The IP address of the node that should be notified when generating
     an error message.

  If a message contains multiple Notify_Request objects, only the first
  object is meaningful.  Subsequent Notify_Request objects MAY be
  ignored and SHOULD NOT be propagated.

4.2.2. Procedures

  A Notify Request object may be inserted in Path or Resv messages to
  indicate the address of a node that should be notified of an LSP
  failure.  As previously mentioned, notifications may be requested in
  both the upstream and downstream directions.  Upstream notification
  is indicated via the inclusion of a Notify Request Object in the
  corresponding Path message.  Downstream notification is indicated via
  the inclusion of a Notify Request Object in the corresponding Resv
  message.






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  A node receiving a message containing a Notify Request object SHOULD
  store the Notify Node Address in the corresponding state block.  If
  the node is a transit node, it SHOULD also included a Notify Request
  object in the outgoing Path or Resv message.  The outgoing Notify
  Node Address MAY be updated based on local policy.

  Note that the inclusion of a Notify Request object does not guarantee
  that a Notify message will be generated.

4.3. Notify Message

  The Notify message provides a mechanism to inform non-adjacent nodes
  of LSP related events.  Notify messages are normally generated only
  after a Notify Request object has been received.  The Notify message
  differs from the currently defined error messages (i.e., PathErr and
  ResvErr messages) in that it can be "targeted" to a node other than
  the immediate upstream or downstream neighbor and that it is a
  generalized notification mechanism.  The Notify message does not
  replace existing error messages.  The Notify message may be sent
  either (a) normally, where non-target nodes just forward the Notify
  message to the target node, similar to ResvConf processing in
  [RFC2205]; or (b) encapsulated in a new IP header whose destination
  is equal to the target IP address.  Regardless of the transmission
  mechanism, nodes receiving a Notify message not destined to the node
  forward the message, unmodified, towards the target.

  To support reliable delivery of the Notify message, an Ack Message
  [RFC2961] is used to acknowledge the receipt of a Notify Message.
  See [RFC2961] for details on reliable RSVP message delivery.

4.3.1. Required Information

  The Notify message is a generalized notification message.  The IP
  destination address is set to the IP address of the intended
  receiver.  The Notify message is sent without the router alert
  option.  A single Notify message may contain notifications being
  sent, with respect to each listed session, both upstream and
  downstream.

  The Notify message has a Message Type of 21.  The Notify message
  format is as follows:

  <Notify message>            ::= <Common Header> [<INTEGRITY>]
                       [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
                                  [ <MESSAGE_ID> ]
                                  <ERROR_SPEC> <notify session list>





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  <notify session list>       ::= [ <notify session list> ]
                                  <upstream notify session> |
                                  <downstream notify session>

  <upstream notify session>   ::= <SESSION> [ <ADMIN_STATUS> ]
                                  [<POLICY_DATA>...]
                                  <sender descriptor>

  <downstream notify session> ::= <SESSION> [<POLICY_DATA>...]
                                  <flow descriptor list>

  The ERROR_SPEC object specifies the error and includes the IP address
  of either the node that detected the error or the link that has
  failed.  See ERROR_SPEC definition in [RFC2205].  The MESSAGE_ID and
  related objects are defined in [RFC2961] and are used when [RFC2961]
  is supported.

4.3.2. Procedures

  Notify messages are most commonly generated at nodes that detect an
  error that will trigger the generation of a PathErr or ResvErr
  message.  If a PathErr message is to be generated and a Notify
  Request object has been received in the corresponding Path message,
  then a Notify message destined to the recorded node SHOULD be
  generated.  If a ResvErr message is to be generated and a Notify
  Request object has been received in the corresponding Resv message,
  then a Notify message destined to the recorded node SHOULD be
  generated.  As previously mentioned, a single error may generate a
  Notify message in both the upstream and downstream directions.  Note
  that a Notify message MUST NOT be generated unless an appropriate
  Notify Request object has been received.

  When generating Notify messages, a node SHOULD attempt to combine
  notifications being sent to the same Notify Node and that share the
  same ERROR_SPEC into a single Notify message.  The means by which a
  node determines which information may be combined is implementation
  dependent.  Implementations may use event, timer based or other
  approaches.  If using a timer based approach, the implementation
  SHOULD allow the user to configure the interval over which
  notifications are combined.  When using a timer based approach, a
  default "notification interval" of 1 ms SHOULD be used.  Notify
  messages SHOULD be delivered using the reliable message delivery
  mechanisms defined in [RFC2961].

  Upon receiving a Notify message, the Notify Node SHOULD send a
  corresponding Ack message.





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4.4. Removing State with a PathErr message

  The PathErr message as defined in [RFC2205] is sent hop-by-hop to the
  source of the associated Path message.  Intermediate nodes may
  inspect this message, but take no action upon it.  In an environment
  where Path messages are routed according to an IGP and that route may
  change dynamically, this behavior is a fine design choice.

  However, when RSVP is used with explicit routes, it is often the case
  that errors can only be corrected at the source node or some other
  node further upstream.  In order to clean up resources, the source
  must receive the PathErr and then either send a PathTear (or wait for
  the messages to timeout).  This causes idle resources to be held
  longer than necessary and increases control message load.  In a
  situation where the control plane is attempting to recover from a
  serious outage, both the message load and the delay in freeing
  resources hamper the ability to rapidly reconverge.

  The situation can be greatly improved by allowing state to be removed
  by intermediate nodes on certain error conditions.  To facilitate
  this a new flag is defined in the ERROR_SPEC object.  The two
  currently defined ERROR_SPEC objects (IPv4 and IPv6 error spec
  objects) each contain a one byte flag field.  Within that field two
  flags are defined.  This specification defines a third flag, 0x04,
  Path_State_Removed.

  The semantics of the Path_State_Removed flag are simply that the node
  forwarding the error message has removed the Path state associated
  with the PathErr.  By default, the Path_State_Removed flag is always
  set to zero when generating or forwarding a PathErr message.  A node
  which encounters an error MAY set this flag if the error results in
  the associated Path state being discarded.  If the node setting the
  flag is not the session endpoint, the node SHOULD generate a
  corresponding PathTear.  A node receiving a PathErr message
  containing an ERROR_SPEC object with the Path_State_Removed flag set
  MAY also remove the associated Path state.  If the Path state is
  removed the Path_State_Removed flag SHOULD be set in the outgoing
  PathErr message.  A node which does not remove the associated Path
  state MUST NOT set the Path_State_Removed flag.  A node that receives
  an error with the Path_State_Removed flag set to zero MUST NOT set
  this flag unless it also generates a corresponding PathTear message.

  Note that the use of this flag does not result in any
  interoperability incompatibilities.







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5. Explicit Label Control

  The Label ERO (Explicit Route Object) and RRO (Record Route Object)
  subobjects are defined to support Explicit Label Control.  Note that
  the Label RRO subobject was defined in [RFC3209] and is being
  extended to support bidirectional LSPs.

5.1. Label ERO subobject

  The Label ERO subobject is defined as follows:

   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
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |L|    Type     |     Length    |U|   Reserved  |   C-Type      |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                             Label                             |
  |                              ...                              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of L, U and Label parameters.

  Type

     3  Label

  Length

     The Length contains the total length of the subobject in bytes,
     including the Type and Length fields.  The Length is always
     divisible by 4.

  C-Type

     The C-Type of the included Label Object.  Copied from the Label
     Object.

5.1.1. Procedures

  The Label subobject follows a subobject containing the IP address, or
  the interface identifier [RFC3477], associated with the link on which
  it is to be used.  Up to two label subobjects may be present, one for
  the downstream label and one for the upstream label.  The following
  SHOULD result in "Bad EXPLICIT_ROUTE object" errors:

  o If the first label subobject is not preceded by a subobject
    containing an IP address, or an interface identifier [RFC3477],
    associated with an output link.



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  o For a label subobject to follow a subobject that has the L-bit set

  o On unidirectional LSP setup, for there to be a label subobject with
    the U-bit set

  o For there to be two label subobjects with the same U-bit values

  To support the label subobject, a node must check to see if the
  subobject following its associate address/interface is a label
  subobject.  If it is, one subobject is examined for unidirectional
  LSPs and two subobjects for bidirectional LSPs.  If the U-bit of the
  subobject being examined is clear (0), then value of the label is
  copied into a new Label_Set object.  This Label_Set object MUST be
  included on the corresponding outgoing Path message.

  If the U-bit of the subobject being examined is set (1), then value
  of the label is label to be used for upstream traffic associated with
  the bidirectional LSP.  If this label is not acceptable, a "Bad
  EXPLICIT_ROUTE object" error SHOULD be generated.  If the label is
  acceptable, the label is copied into a new Upstream_Label object.
  This Upstream_Label object MUST be included on the corresponding
  outgoing Path message.

  After processing, the label subobjects are removed from the ERO.

  Note an implication of the above procedures is that the label
  subobject should never be the first subobject in a newly received
  message.  If the label subobject is the the first subobject an a
  received ERO, then it SHOULD be treated as a "Bad strict node" error.

  Procedures by which an LSR at the head-end of an LSP obtains the
  information needed to construct the Label subobject are outside the
  scope of this document.

5.2. Label RRO subobject

  The Label RRO subobject is defined as follows:

   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    |U|   Flags     |   C-Type      |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                             Label                             |
  |                              ...                              |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of U and Label parameters.



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  Type

     3  Label

  Length

     See [RFC3209].

  Flags

     See [RFC3209].

  C-Type

     The C-Type of the included Label Object.  Copied from the Label
     Object.

5.2.1. Procedures

  Label RRO subobjects are included in RROs as described in [RFC3209].
  The only modification to usage and processing from [RFC3209] is that
  when labels are recorded for bidirectional LSPs, label ERO subobjects
  for both downstream and upstream labels MUST be included.

6. Protection Object

  The use of the Protection Object is optional.  The object is included
  to indicate specific protection attributes of an LSP.  The Protection
  Object uses Class-Number 37 (of form 0bbbbbbb).

  The format of the Protection Object is:

   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 (37)|   C-Type (1)  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |S|                  Reserved                       | Link Flags|
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of parameters.










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6.1. Procedures

  Transit nodes processing a Path message containing a Protection
  Object MUST verify that the requested protection can be satisfied by
  the outgoing interface or tunnel (FA).  If it cannot, the node MUST
  generate a PathErr message, with a "Routing problem/Unsupported Link
  Protection" indication.

7. Administrative Status Information

  Administrative Status Information is carried in the Admin_Status
  object.  The object provides information related to the
  administrative state of a particular LSP.  The information is used in
  two ways.  In the first, the object is carried in Path and Resv
  messages to indicate the administrative state of an LSP.  In the
  second, the object is carried in a Notification message to request
  that the ingress node change the administrative state of an LSP.

7.1. Admin Status Object

  The use of the Admin_Status Object is optional.  It uses Class-Number
  196 (of form 11bbbbbb).

  The format of the Admin_Status Object is:

   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                       |T|A|D|
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC3471] for a description of parameters.

7.2. Path and Resv Message Procedures

  The Admin_Status object is used to notify each node along the path of
  the status of the LSP.  Status information is processed by each node
  based on local policy and then propagated in the corresponding
  outgoing messages.  The object may be inserted in either Path or Resv
  messages at the discretion of the ingress (for Path messages) or
  egress (for Resv messages) nodes.  The absence of the object is
  equivalent to receiving an object containing values all set to zero
  (0).






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  Transit nodes receiving a non-refresh Path or Resv message containing
  an Admin_Status object, update their local state, take any
  appropriate local action based on the indicated status and then
  propagate the received Admin_Status object in the corresponding
  outgoing Path or Resv message.  If the values of an Admin_Status
  object received in a Resv message differs from the values received in
  a Path message then, with one exception, no local action should be
  taken but the values should still be propagated.  The one case where
  values received in the Resv message should result in local action is
  when both the received R and D bits are set, i.e., are one (1).

  Edge nodes receiving a non-refresh Path or Resv message containing an
  Admin_Status object, also update their local state and take any
  appropriate local action based on the indicated status.  When an
  Admin Status object is received with the R bit set, the receiving
  edge node should reflect the received values in a corresponding
  outgoing message.  Specifically, if an egress node receives a Path
  message with the R bit of the Admin_Status object set and the node
  has previously issued a Resv message corresponding to the Path
  message, the node SHOULD send an updated Resv message containing an
  Admin_Status object with the same values set, with the exception of
  the R bit, as received in the corresponding Path message.
  Furthermore, the egress node SHOULD also ensure that subsequent Resv
  messages sent by the node contain the same Admin Status Object.

  Additionally, if an ingress node receives a Resv message with the R
  bit of the Admin_Status object set, the node SHOULD send an updated
  Path message containing an Admin_Status object with the same values
  set, with the exception of the R bit, as received in the
  corresponding Resv message.  Furthermore, the ingress node SHOULD
  also ensure that subsequent Path messages sent by the node contain
  the same Admin Status Object.

7.2.1. Deletion procedure

  In some circumstances, particularly optical networks, it is useful to
  set the administrative status of an LSP before tearing it down.  In
  such circumstances the procedure SHOULD be followed when deleting an
  LSP from the ingress:

  1. The ingress node precedes an LSP deletion by inserting an Admin
     Status Object in a Path message and setting the Reflect (R) and
     Delete (D) bits.

  2. Transit and egress nodes process the Admin Status Object as
     described above.  (Alternatively, the egress MAY respond with a
     PathErr message with the Path_State_Removed flag set, see section
     4.4.)



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  3. Upon receiving the Admin Status Object with the Delete (D) bit set
     in the Resv message, the ingress node sends a PathTear message
     downstream to remove the LSP and normal RSVP processing takes
     place.

  In such circumstances the procedure SHOULD be followed when deleting
  an LSP from the egress:

  1. The egress node indicates its desire for deletion by inserting an
     Admin Status Object in a Resv message and setting the Reflect (R)
     and Delete (D) bits.

  2. Transit nodes process the Admin Status Object as described above.

  3. Upon receiving the Admin Status Object with the Delete (D) bit set
     in the Resv message, the ingress node sends a PathTear message
     downstream to remove the LSP and normal RSVP processing takes
     place.

7.2.2. Compatibility and Error Procedures

  It is possible that some nodes along an LSP will not support the
  Admin Status Object.  In the case of a non-supporting transit node,
  the object will pass through the node unmodified and normal
  processing can continue.  In the case of a non-supporting egress
  node, the Admin Status Object will not be reflected back in the Resv
  Message.  To support the case of a non-supporting egress node, the
  ingress SHOULD only wait a configurable period of time for the
  updated Admin Status Object in a Resv message.  Once the period of
  time has elapsed, the ingress node sends a PathTear message.  By
  default this period of time SHOULD be 30 seconds.

7.3. Notify Message Procedures

  Intermediate and egress nodes may trigger the setting of
  administrative status via the use of Notify messages.  To accomplish
  this, an intermediate or egress node generates a Notify message with
  the corresponding upstream notify session information.  The Admin
  Status Object MUST be included in the session information, with the
  appropriate bit or bits set.  The Reflect (R) bit MUST NOT be set.
  The Notify message may be, but is not required to be, encapsulated,
  see Section 4.3.

  An ingress node receiving a Notify message containing an Admin Status
  Object with the Delete (D) bit set, SHOULD initiate the deletion
  procedure described in the previous section.  Other bits SHOULD be
  propagated in an outgoing Path message as normal.




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7.3.1. Compatibility and Error Procedures

  Some special processing is required in order to cover the case of
  nodes that do not support the Admin Status Object and other error
  conditions.  Specifically, a node that sends a Notify message
  containing an Admin Status Object with the Down (D) bit set MUST
  verify that it receives a corresponding Path message with the Down
  (D) bit set within a configurable period of time.  By default this
  period of time SHOULD be 30 seconds.  If the node does not receive
  such a Path message, it SHOULD send a PathTear message downstream and
  either a ResvTear message or a PathErr message with the
  Path_State_Removed flag set upstream.

8. Control Channel Separation

  This section provides the protocol specific formats and procedures to
  required support a control channel not being in-band with a data
  channel.

8.1. Interface Identification

  The choice of the data interface to use is always made by the sender
  of the Path message. The choice of the data interface is indicated by
  the sender of the Path message by including the data channel's
  interface identifier in the message using a new RSVP_HOP object sub-
  type.  For bidirectional LSPs, the sender chooses the data interface
  in each direction.  In all cases but bundling, the upstream interface
  is implied by the downstream interface.  For bundling, the path
  sender explicitly identifies the component interface used in each
  direction.  The new RSVP_HOP object is used in Resv message to
  indicate the downstream node's usage of the indicated interface(s).




















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8.1.1. IF_ID RSVP_HOP Objects

  The format of the IPv4 IF_ID RSVP_HOP Object is:

   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 (3) | C-Type (3)    |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                 IPv4 Next/Previous Hop Address                |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                     Logical Interface Handle                  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  ~                              TLVs                             ~
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  The format of the IPv6 IF_ID RSVP_HOP Object is:

   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 (3) | C-Type (4)    |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  |                 IPv6 Next/Previous Hop Address                |
  |                                                               |
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                     Logical Interface Handle                  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  ~                              TLVs                             ~
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


  See [RFC2205] for a description of hop address and handle fields.
  See [RFC3471] for a description of parameters and encoding of
  TLVs.










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8.1.2. Procedures

  An IF_ID RSVP_HOP object is used in place of previously defined
  RSVP_HOP objects.  It is used on links where there is not a one-to-
  one association of a control channel to a data channel, see
  [RFC3471].  The Hop Address and Logical Interface Handle fields are
  used per standard RSVP [RFC2205].

  TLVs are used to identify the data channel(s) associated with an LSP.
  For a unidirectional LSP, a downstream data channel MUST be
  indicated.  For bidirectional LSPs, a common downstream and upstream
  data channel is normally indicated.  In the special case where a
  bidirectional LSP that traverses a bundled link, it is possible to
  specify a downstream data channel that differs from the upstream data
  channel.  Data channels are specified from the viewpoint of the
  sender of the Path message.  The IF_ID RSVP_HOP object SHOULD NOT be
  used when no TLVs are needed.

  A node receiving one or more TLVs in a Path message saves their
  values and returns them in the HOP objects of subsequent Resv
  messages sent to the node that originated the TLVs.

  Note, the node originating an IF_ID object MUST ensure that the
  selected outgoing interface, as specified in the IF_ID object, is
  consistent with an ERO.  A node that receives an IF_ID object SHOULD
  check whether the information carried in this object is consistent
  with the information carried in a received ERO, and if not it MUST
  send a PathErr Message with the error code "Routing Error" and error
  value of "Bad Explicit Route Object" toward the sender.  This check
  CANNOT be performed when the initial ERO subobject is not the
  incoming interface.

8.2. Errored Interface Identification

  There are cases where it is useful to indicate a specific interface
  associated with an error.  To support these cases the IF_ID
  ERROR_SPEC Objects are defined.














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8.2.1. IF_ID ERROR_SPEC Objects

  The format of the IPv4 IF_ID ERROR_SPEC Object is:

   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 (6) | C-Type (3)    |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                     IPv4 Error Node Address                   |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |     Flags     |   Error Code  |          Error Value          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  ~                              TLVs                             ~
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  The format of the IPv6 IF_ID ERROR_SPEC Object is:

   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 (6) | C-Type (4)    |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  |                     IPv6 Error Node Address                   |
  |                                                               |
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |     Flags     |   Error Code  |          Error Value          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                                                               |
  ~                              TLVs                             ~
  |                                                               |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  See [RFC2205] for a description of address, flags, error code and
  error value fields.  See [RFC3471] for a description of parameters
  and encoding of TLVs.

8.2.2. Procedures

  Nodes wishing to indicate that an error is related to a specific
  interface SHOULD use the appropriate IF_ID ERROR_SPEC Object in the
  corresponding PathErr or ResvErr message.  IF_ID ERROR_SPEC Objects
  SHOULD be generated and processed as any other ERROR_SPEC Object, see
  [RFC2205].



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9. Fault Handling

  The handling of two types of control communication faults is
  described in this section.  The first, referred to as nodal faults,
  relates to the case where a node losses its control state (e.g.,
  after a restart) but does not loose its data forwarding state.  In
  the second, referred to as control channel faults, relates to the
  case where control communication is lost between two nodes.  The
  handling of both faults is supported by the Restart_Cap object
  defined below and require the use of Hello messages.

  Note, the Restart_Cap object MUST NOT be sent when there is no
  mechanism to detect data channel failures independent of control
  channel failures.

  Please note this section is derived from [PAN-RESTART].

9.1. Restart_Cap Object

  The Restart_Cap Object is carried in Hello messages.

  The format of the Restart_Cap Object is:

   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(131)|  C-Type  (1)  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                         Restart Time                          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  |                        Recovery Time                          |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

  Restart Time: 32 bits

     Restart Time is measured in milliseconds.  Restart Time SHOULD be
     set to the sum of the time it takes the sender of the object to
     restart its RSVP-TE component (to the point where it can exchange
     RSVP Hello with its neighbors) and the communication channel that
     is used for RSVP communication.  A value of 0xffffffff indicates
     that the restart of the sender's control plane may occur over an
     indeterminate interval and that the operation of its data plane is
     unaffected by control plane failures.  The method used to ensure
     continued data plane operation is outside the scope of this
     document.






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  Recovery Time: 32 bits

     The period of time, in milliseconds, that the sender desires for
     the recipient to re-synchronize RSVP and MPLS forwarding state
     with the sender after the re-establishment of Hello
     synchronization.  A value of zero (0) indicates that MPLS
     forwarding state was not preserved across a particular reboot.

9.2. Processing of Restart_Cap Object

  Nodes supporting state recovery advertise this capability by carrying
  the Restart_Cap object in Hello messages.  Such nodes MUST include
  the Restart_Cap object in all Hello messages. (Note that this
  includes Hello messages containing ACK objects.)  Usage of the
  special case Recovery Time values is described in greater detail
  below.

  When a node receives a Hello message with the Restart_Cap object, it
  SHOULD record the values of the parameters received.

9.3. Modification to Hello Processing to Support State Recovery

  When a node determines that RSVP communication with a neighbor has
  been lost, and the node previously learned that the neighbor supports
  state recovery, the node SHOULD wait at least the amount of time
  indicated by the Restart Time indicated by the neighbor before
  invoking procedures related to communication loss.  A node MAY wait a
  different amount of time based on local policy or configuration
  information.

  During this waiting period, all Hello messages MUST be sent with a
  Dst_Instance value set to zero (0), and Src_Instance should be
  unchanged.  While waiting, the node SHOULD also preserve the RSVP and
  MPLS forwarding state for (already) established LSPs that traverse
  the link(s) between the node and the neighbor.  In a sense with
  respect to established LSPs the node behaves as if it continues to
  receive periodic RSVP refresh messages from the neighbor.  The node
  MAY clear RSVP and forwarding state for the LSPs that are in the
  process of being established when their refresh timers expire.
  Refreshing of Resv and Path state SHOULD be suppressed during this
  waiting period.

  During this waiting period, the node MAY inform upstream nodes of the
  communication loss via a PathErr and/or upstream Notify message with
  "Control Channel Degraded State" indication.  If such notification
  has been sent, then upon restoration of the control channel the node





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  MUST inform other nodes of the restoration via a PathErr and/or
  upstream Notify message with "Control Channel Active State"
  indication.  (Specific error codes have been assigned by IANA.)

  When a new Hello message is received from the neighbor, the node must
  determine if the fault was limited to the control channel or was a
  nodal fault.  This determination is based on the Src_Instance
  received from the neighbor.  If the value is different than the value
  that was received from the neighbor prior to the fault, then the
  neighbor should be treated as if it has restarted.  Otherwise, the
  the fault was limited control channel.  Procedures for handling each
  case are described below.

9.4. Control Channel Faults

  In the case of control channel faults, the node SHOULD refresh all
  state shared with the neighbor.  Summary Refreshes [RFC2961] with the
  ACK_Desired flag set SHOULD be used, if supported.  Note that if a
  large number of messages are need, some pacing should be applied.
  All state SHOULD be refreshed within the Recovery time advertised by
  the neighbor.

9.5. Nodal Faults

  Recovering from nodal faults uses one new object and other existing
  protocol messages and objects.

9.5.1. Recovery Label

  The Recovery_Label object is used during the nodal fault recovery
  process.  The format of a Recovery_Label object is identical to a
  generalized label.  A Recovery_Label object uses Class-Number 34 (of
  form 0bbbbbbb) and the C-Type of the label being suggested.

9.5.2. Procedures for the Restarting node

  After a node restarts its control plane, a node that supports state
  recovery SHOULD check whether it was able to preserve its MPLS
  forwarding state.  If no forwarding state from prior to the restart
  was preserved, then the node MUST set the Recovery Time to 0 in the
  Hello message the node sends to its neighbors.

  If the forwarding state was preserved, then the node initiates the
  state recovery process.  The period during which a node is prepared
  to support the recovery process is referred to as the Recovery
  Period.  The total duration of the Recovery Period is advertised by
  the recovering node in the Recovery Time parameter of the Restart_Cap
  object.  The Recovery Time MUST be set to the duration of the



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  Recovery Period in all Hello messages sent during the Recovery
  Period.  State that is not resynchronized during the Recovery Period
  SHOULD be removed at the end of the Period.

  Note that if during Hello synchronization the restarting node
  determines that a neighbor does not support state recovery, and the
  restarting node maintains its MPLS forwarding state on a per neighbor
  basis, the restarting node should immediately consider the Recovery
  Period with that neighbor completed.  Forwarding state may be
  considered to be maintained on a per neighbor basis when per
  interface labels are used on point-to-point interfaces.

  When a node receives a Path message during the Recovery Period, the
  node first checks if it has an RSVP state associated with the
  message.  If the state is found, then the node handles this message
  according to previously defined procedures.

  If the RSVP state is not found, and the message does not carry a
  Recovery_Label object, the node treats this as a setup for a new LSP,
  and handles it according to previously defined procedures.

  If the RSVP state is not found, and the message carries a
  Recovery_Label object, the node searches its MPLS forwarding table
  (the one that was preserved across the restart) for an entry whose
  incoming interface matches the Path message and whose incoming label
  is equal to the label carried in the Recovery_Label object.

  If the MPLS forwarding table entry is not found, the node treats this
  as a setup for a new LSP, and handles it according to previously
  defined procedures.

  If the MPLS forwarding table entry is found, the appropriate RSVP
  state is created, the entry is bound to the LSP associated with the
  message, and related forwarding state should be considered as valid
  and refreshed.  Normal Path message processing should also be
  conducted.  When sending the corresponding outgoing Path message the
  node SHOULD include a Suggested_Label object with a label value
  matching the outgoing label from the now restored forwarding entry.
  The outgoing interface SHOULD also be selected based on the
  forwarding entry.  In the special case where a restarting node also
  has a restating downstream neighbor, a Recovery_Label object should
  be used instead of a Suggested_Label object.

  Additionally, for bidirectional LSPs, the node extracts the label
  from the UPSTREAM_LABEL object carried in the received Path message,
  and searches its MPLS forwarding table for an entry whose outgoing





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  label is equal to the label carried in the object (in the case of
  link bundling, this may also involved first identifying the
  appropriate incoming component link).

  If the MPLS forwarding table entry is not found, the node treats this
  as a setup for a new LSP, and handles it according to previously
  defined procedures.

  If the MPLS forwarding table entry is found, the entry is bound to
  the LSP associated with the Path message, and the entry should be
  considered to be re-synchronized.  In addition, if the node is not
  the tail-end of the LSP, the corresponding outgoing Path messages is
  sent with the incoming label from that entry carried in the
  UPSTREAM_LABEL object.

  During the Recovery Period, Resv messages are processed normally with
  two exceptions.  In the case that a forwarding entry is recovered, no
  new label or resource allocation is required while processing the
  Resv message.  The second exception is that ResvErr messages SHOULD
  NOT be generated when a Resv message with no matching Path state is
  received.  In this case the Resv message SHOULD just be silently
  discarded.

9.5.3. Procedures for the Neighbor of a Restarting node

  The following specifies the procedures that apply when the node
  reestablishes communication with the neighbor's control plane within
  the Restart Time, the node determines (using the procedures defined
  in Section 5 of [RFC3209]) that the neighbor's control plane has
  restarted, and the neighbor was able to preserve its forwarding state
  across the restart (as was indicated by a non-zero Recovery Time
  carried in the Restart_Cap object of the RSVP Hello messages received
  from the neighbor).  Note, a Restart Time value of 0xffffffff
  indicates an infinite Restart Time interval.

  Upon detecting a restart with a neighbor that supports state
  recovery, a node SHOULD refresh all Path state shared with that
  neighbor.  The outgoing Path messages MUST include a Recovery_Label
  object containing a label value corresponding to the label value
  received in the most recently received corresponding Resv message.
  All Path state SHOULD be refreshed within approximately 1/2 of the
  Recovery time advertised by the restarted neighbor.  If there are
  many LSP's going through the restarting node, the neighbor node
  should avoid sending Path messages in a short time interval, as to
  avoid unnecessary stressing the restarting node's CPU.  Instead, it
  should spread the messages across 1/2 the Recovery Time interval.





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  After detecting a restart of a neighbor that supports state recovery,
  all Resv state shared with the restarting node MUST NOT be refreshed
  until a corresponding Path message is received.  This requires
  suppression of normal Resv and Summary Refresh processing to the
  neighbor during the Recovery Time advertised by the restarted
  neighbor.  As soon as a corresponding Path message is received a Resv
  message SHOULD be generated and normal state processing SHOULD be
  re-enabled.

10. RSVP Message Formats and Handling

  This message summarizes RSVP message formats and handling as modified
  by GMPLS.

10.1. RSVP Message Formats

  This section presents the RSVP message related formats as modified by
  this document.  Where they differ, formats for unidirectional LSPs
  are presented separately from bidirectional LSPs.  Unmodified formats
  are not listed.  Again, MESSAGE_ID and related objects are defined in
  [RFC2961].

  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> ... ]
                        <sender descriptor>













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  The format of the sender description for unidirectional LSPs is:

<sender descriptor> ::=  <SENDER_TEMPLATE> <SENDER_TSPEC>
                        [ <ADSPEC> ]
                        [ <RECORD_ROUTE> ]
                        [ <SUGGESTED_LABEL> ]
                        [ <RECOVERY_LABEL> ]

  The format of the sender description for bidirectional LSPs is:

<sender descriptor> ::=  <SENDER_TEMPLATE> <SENDER_TSPEC>
                        [ <ADSPEC> ]
                        [ <RECORD_ROUTE> ]
                        [ <SUGGESTED_LABEL> ]
                        [ <RECOVERY_LABEL> ]
                        <UPSTREAM_LABEL>

  The format of a PathErr message is as follows:

<PathErr Message> ::=    <Common Header> [ <INTEGRITY> ]
                        [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
                        [ <MESSAGE_ID> ]
                        <SESSION> <ERROR_SPEC>
                        [ <ACCEPTABLE_LABEL_SET> ... ]
                        [ <POLICY_DATA> ... ]
                        <sender descriptor>

  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> ... ]
                        <STYLE> <flow descriptor list>

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










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  The format of a ResvErr message is as follows:

<ResvErr Message> ::=    <Common Header> [ <INTEGRITY> ]
                        [ [<MESSAGE_ID_ACK> | <MESSAGE_ID_NACK>] ... ]
                        [ <MESSAGE_ID> ]
                        <SESSION> <RSVP_HOP>
                        <ERROR_SPEC> [ <SCOPE> ]
                        [ <ACCEPTABLE_LABEL_SET> ... ]
                        [ <POLICY_DATA> ... ]
                        <STYLE> <error flow descriptor>

  The modified Hello message format is:

<Hello Message> ::= <Common Header> [ <INTEGRITY> ] <HELLO>
                   [ <RESTART_CAP> ]

10.2. Addressing Path, PathTear and ResvConf Messages

  RSVP was designed to handle dynamic (non-explicit) path changes and
  non RSVP hops along the path.  To this end, the Path, PathTear and
  ResvConf messages carry the destination address of the session in the
  IP header.  In generalized signaling, routes are usually explicitly
  signaled.  Further, hops that cannot allocate labels cannot exist in
  the path of an LSP.  A further difference with traditional RSVP is
  that at times, an RSVP message may travel out of band with respect to
  an LSP's data channel.

  When a node is sending a Path, PathTear or ResvConf message to a node
  that it knows to be adjacent at the data plane (i.e., along the path
  of the LSP), it SHOULD address the message directly to an address
  associated with the adjacent node's control plane.  In this case the
  router-alert option SHOULD not be included.

11. Acknowledgments

  This document is the work of numerous authors and consists of a
  composition of a number of previous documents in this area.

  Valuable comments and input were received from a number of people,
  including Igor Bryskin, Adrian Farrel and Dimitrios Pendarakis.
  Portions of Section 4 are based on suggestions and text proposed by
  Adrian Farrel.

  The security considerations section is based on text provided by
  Steven Bellovin.






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12. Security Considerations

  RSVP message security is described in [RFC2747] and provides message
  integrity and node authentication.  For hop-by-hop messages, this
  document introduces no other new security considerations.

  This document introduces the ability to send a Notify message in a
  non-hop-by-hop fashion.  This precludes RSVP's hop-by-hop integrity
  and authentication model.  In the case where RSVP is generating end-
  to-end messages and the same level of security provided by [RFC2747]
  is desired, the standard IPSEC based integrity and authentication can
  be used.  Alternatively, the sending of no-hop-by-hop Notify messages
  can be disabled.

  When using IPSEC to provide message authentication, the following
  apply:

     Selectors
        The selector is identified by RSVP messages exchanged between a
        pair of non-adjacent nodes.  The nodes are identified by the
        source and destination IP address of the inner IP header used
        on Notify messages.

     Mode
        In this application, transport mode is the proper choice.  The
        information being communicated is generally not confidential,
        so encryption need not be used.  Either AH [RFC2402] or ESP
        [RFC2406] MAY be used; if ESP is used, the sender's IP address
        MUST be checked against the IP address asserted in the key
        management exchange.

     Key Management
        To permit replay detection, an automated key management system
        SHOULD be used, most likely IKE [RFC2409].  Configured keys MAY
        be used.

     Security Policy
        Messages MUST NOT be accepted except from nodes that are not
        known to the recipient to be authorized to make such requests.

     Identification
        Shared keys mechanisms should be adequate for initial
        deployments and smaller networks.  For larger-scale
        deployments, certificate-based IKE should be supported.
        Whatever scheme is used, it must tie back to a source IP
        address in some fashion.





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     Availability
        Many routers and switches already support IPSEC.  For cases
        where IPSEC is unavailable and security is required, Notify
        messages MUST be sent hop-by-hop.

13. IANA Considerations

  IANA assigns values to RSVP protocol parameters.  Within the current
  document multiple objects are defined.  Each of these objects contain
  C-Types.  This section defines the rules for the assignment of the
  related C-Type values.  This section uses the terminology of BCP 26
  "Guidelines for Writing an IANA Considerations Section in RFCs"
  [BCP26].

  As per [RFC2205], C-Type is an 8-bit number that identifies the
  function of an object.  All possible values except zero are available
  for assignment.

  The assignment of C-Type values of the objects defined in this
  document fall into three categories.  The first category inherit C-
  Types from the Label object, i.e., object class number 16 [RFC3209].
  IANA is requested to institute a policy whereby all C-Type values
  assign for the Label object are also assigned for the following
  objects:

     o Suggested_Label    (Class-Num 129)
     o Upstream_Label     (Class-Num 35)
     o Recovery_Label     (Class-Num 34)

  The second category of objects follow independent policies.
  Specifically, following the policies outlined in [BCP26], C-Type
  values in the range 0x00 - 0x3F are allocated through an IETF
  Consensus action, values in the range 00x40 - 0x5F are allocated as
  First Come First Served, and values in the range 0x60 - 0x7F are
  reserved for Private Use.  This policy applies to the following
  objects.

     o Label_Set          (Class-Num 36)
     o Notify_Request     (Class-Num 195)
     o Protection         (Class-Num 37)
     o Admin Status       (Class-Num 196)
     o Restart_Cap        (Class-Num 131)

  The assignment of C-Type values for the remaining object, the
  Acceptable_Label_Set object, follows the assignment of C-Type values
  of the Label_Set object.  IANA will institute a policy whereby all
  C-Type values assigned for the Label_Set object are also assigned for
  the Acceptable_Label_Set object.



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13.1. IANA Assignments

  This section summarizes values used in this document that have been
  assigned by IANA.

  ---------------------------------------------------------------------
  Message Types

  o Notify message (Message type = 21)

  ---------------------------------------------------------------------
  Class Types

  o RSVP_HOP (C-Num 3)
    - IPv4 IF_ID RSVP_HOP (C-type = 3)
    - IPv6 IF_ID RSVP_HOP (C-type = 4)

  o ERROR_SPEC (C-Num 6)
    - IPv4 IF_ID ERROR_SPEC (C-type = 3)
    - IPv6 IF_ID ERROR_SPEC (C-type = 4)

  o LABEL_REQUEST (Class-Num 19)
    - Generalized_Label_Request (C-Type = 4)

  o RSVP_LABEL (Class-Num = 16)
    - Generalized_Label (C-Type = 2)
    - Waveband_Switching_Label C-Type (C-Type = 3)

  ---------------------------------------------------------------------
  New Class-Nums, C-Types inherited from Label object (same as CNum16)

  o RECOVERY_LABEL     Class-Num of form 0bbbbbbb (= 34)
  o SUGGESTED_LABEL    Class-Num of form 10bbbbbb (= 129)
  o UPSTREAM_LABEL     Class-Num of form 0bbbbbbb (= 35)


  ---------------------------------------------------------------------
  New Class-Nums

  o LABEL_SET                 Class-Num of form 0bbbbbbb (= 36)
    - Type 1               (C-Type = 1)
  o ACCEPTABLE_LABEL_SET      Class-Num of form 10bbbbbb (= 130)
    - Type 1 Acceptable_Label_Set (C-type from label_set cnum)
  o NOTIFY_REQUEST            Class-Num of form 11bbbbbb (= 195)
    - IPv4 Notify Request  (C-Type = 1)
    - IPv6 Notify Request  (C-Type = 2)
  o PROTECTION                Class-Num of form 0bbbbbbb (= 37)
    - Type 1               (C-Type = 1)



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  o ADMIN STATUS              Class-Num of form 11bbbbbb (= 196)
    - Type 1               (C-Type = 1)
  o RESTART_CAP               Class-Num of form 10bbbbbb (= 131)
    - Type 1               (C-Type = 1)
  ---------------------------------------------------------------------
  ERO/RRO subobject types

  o Label ERO subobject
    Type 3 - Label

  o Label RRO subobject
    Type 3 - Label
  ---------------------------------------------------------------------
  Error codes

  o "Routing problem/Label Set"                   (value = 11)
  o "Routing problem/Switching Type"              (value = 12)
                                       (duplicate code 13 dropped)
  o "Routing problem/Unsupported Encoding"        (value = 14)
  o "Routing problem/Unsupported Link Protection" (value = 15)
  o "Notify Error/Control Channel Active State"   (value = 4)
  o "Notify Error/Control Channel Degraded State" (value = 5)
  ---------------------------------------------------------------------

14. Intellectual Property Considerations

  This section is taken from Section 10.4 of [RFC2026].

  The IETF takes no position regarding the validity or scope of any
  intellectual property 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; neither does it represent that it
  has made any effort to identify any such rights.  Information on the
  IETF's procedures with respect to rights in standards-track and
  standards-related documentation can be found in BCP-11.  Copies of
  claims of rights made available for publication 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 implementors or users of this specification can
  be obtained from the IETF Secretariat.

  The IETF invites any interested party to bring to its attention any
  copyrights, patents or patent applications, or other proprietary
  rights which may cover technology that may be required to practice
  this standard.  Please address the information to the IETF Executive
  Director.




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15. References

15.1. Normative References

  [RFC2119]        Bradner, S., "Key words for use in RFCs to Indicate
                   Requirement Levels", BCP 14, RFC 2119, March 1997.

  [RFC2205]        Braden, R. (Ed.), Zhang, L., Berson, S., Herzog, S.
                   and S. Jamin, "Resource ReserVation Protocol --
                   Version 1 Functional Specification", RFC 2205,
                   September 1997.

  [RFC2210]        Wroclawski, J., "The Use of RSVP with IETF
                   Integrated Services", RFC 2210, September 1997.

  [RFC2402]        Kent, S. and R. Atkinson, "IP Authentication
                   Header", RFC 2401, November 1998.

  [RFC2406]        Kent, S. and R. Atkinson, "IP Encapsulating Security
                   Payload (ESP)", RFC 2401, November 1998.

  [RFC2409]        Harkins, D. and D. Carrel, "The Internet Key
                   Exchange (IKE)", RFC 2409, November 1998.

  [RFC2747]        Baker, F., Lindell, B. and M. Talwar, "RSVP
                   Cryptographic Authentication", RFC 2747, January
                   2000.

  [RFC2961]        Berger, L., Gan, D., Swallow, G., Pan, P., Tommasi,
                   F. and S. Molendini, "RSVP Refresh Overhead
                   Reduction Extensions", RFC 2961, April 2001.

  [RFC3209]        Awduche, D., Berger, L., Gan, D., Li, T.,
                   Srinivasan, V. and G. Swallow, "RSVP-TE: Extensions
                   to RSVP for LSP Tunnels", RFC 3209, December 2001.

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

  [RFC3477]        Kompella, K. and Y. Rekhter, "Signalling Unnumbered
                   Links in Resource Reservation Protocol - Traffic
                   Engineering (RSVP-TE)", RFC 3477, January 2003.








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15.2. Informative References

  [BCP26]          Narten, T. and H. Alvestrand, "Guidelines for
                   Writing an IANA Considerations Section in RFCs", BCP
                   26, RFC 2434, October 1998.

  [MPLS-HIERARCHY] Kompella, K. and Y. Rekhter, "LSP Hierarchy with
                   MPLS TE", Work in Progress.

  [PAN-RESTART]    Pan, P., et. al., "Graceful Restart Mechanism for
                   RSVP-TE", Work in Progress.

  [RFC2026]        Bradner, S., "The Internet Standards Process --
                   Revision 3", BCP 9, RFC 2026, October 1996.

16. Contributors

  Peter Ashwood-Smith
  Nortel Networks Corp.
  P.O. Box 3511 Station C,
  Ottawa, ON K1Y 4H7
  Canada

  Phone:  +1 613 763 4534
  EMail:  [email protected]


  Ayan Banerjee
  Calient Networks
  5853 Rue Ferrari
  San Jose, CA 95138

  Phone:  +1 408 972-3645
  EMail:  [email protected]


  Lou Berger
  Movaz Networks, Inc.
  7926 Jones Branch Drive
  Suite 615
  McLean VA, 22102

  Phone:  +1 703 847-1801
  EMail:  [email protected]







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  Greg Bernstein
  EMail:  [email protected]


  John Drake
  Calient Networks
  5853 Rue Ferrari
  San Jose, CA 95138

  Phone:  +1 408 972 3720
  EMail:  [email protected]


  Yanhe Fan
  Axiowave Networks, Inc.
  200 Nickerson Road
  Marlborough, MA 01752

  Phone: + 1 774 348 4627
  EMail: [email protected]


  Kireeti Kompella
  Juniper Networks, Inc.
  1194 N. Mathilda Ave.
  Sunnyvale, CA 94089

  EMail:  [email protected]


  Jonathan P. Lang
  EMail:  [email protected]


  Fong Liaw
  Solas Research, LLC

  EMail:  [email protected]













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  Eric Mannie
  Independent Consultant
  2 Avenue de la Folle Chanson
  1050 Brussels
  Belgium

  EMail:  [email protected]


  Ping Pan
  Ciena
  10480 Ridgeview Court
  Cupertino, CA 95014

  Phone:  408-366-4700
  EMail:  [email protected]


  Bala Rajagopalan
  Tellium, Inc.
  2 Crescent Place
  P.O. Box 901
  Oceanport, NJ 07757-0901

  Phone:  +1 732 923 4237
  Fax:    +1 732 923 9804
  EMail:  [email protected]


  Yakov Rekhter
  Juniper Networks, Inc.

  EMail:  [email protected]


  Debanjan Saha
  EMail:  [email protected]














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  Vishal Sharma
  Metanoia, Inc.
  1600 Villa Street, Unit 352
  Mountain View, CA 94041-1174

  Phone:  +1 650-386-6723
  EMail:  [email protected]


  George Swallow
  Cisco Systems, Inc.
  250 Apollo Drive
  Chelmsford, MA 01824

  Phone:  +1 978 244 8143
  EMail:  [email protected]


  Z. Bo Tang
  EMail:  [email protected]

17. Editor's Address

  Lou Berger
  Movaz Networks, Inc.
  7926 Jones Branch Drive
  Suite 615
  McLean VA, 22102

  Phone:  +1 703 847-1801
  EMail:  [email protected]




















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18.  Full Copyright Statement

  Copyright (C) The Internet Society (2003).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS 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.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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