Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Path Diversity using Exclude Routes
draft-ietf-ccamp-lsp-diversity-01
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
|
|
|---|---|---|---|
| Authors | Zafar Ali , George Swallow , Clarence Filsfils , Matt Hartley , Ori Gerstel , Gabriele Galimberti , Kenji Kumaki , Ruediger Kunze , Julien Meuric | ||
| Last updated | 2013-02-18 | ||
| Replaces | draft-ali-ccamp-xro-lsp-subobject | ||
| Replaced by | draft-ietf-teas-lsp-diversity, draft-ietf-teas-lsp-diversity, RFC 8390 | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Formats | |||
| Additional resources | Mailing list discussion | ||
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| Document shepherd | (None) | ||
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| Consensus boilerplate | Unknown | ||
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draft-ietf-ccamp-lsp-diversity-01
CCAMP Working Group Zafar Ali
Internet Draft George Swallow
Intended status: Standard Track Clarence Filsfils
Expires: August 17, 2013 Matt Hartley
Ori Gerstel
Gabriele Maria Galimberti
Cisco Systems
Kenji Kumaki
KDDI Corporation
Ruediger Kunze
Deutsche Telekom AG
Julien Meuric
France Telecom Orange
February 18, 2013
Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Path
Diversity using Exclude Routes
draft-ietf-ccamp-lsp-diversity-01.txt
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Abstract
RFC 4874 specifies methods by which route exclusions may be
communicated during RSVP-TE signaling in networks where precise
explicit paths are not computed by the LSP source node. This
document specifies signaling for additional route exclusions based
on Paths currently existing or expected to exist within the network.
Conventions used in this document
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 RFC 2119 [RFC2119].
Table of Contents
1. Introduction ..................................................3
2. RSVP-TE signaling extensions ..................................5
2.1. Terminology .................................................5
2.2. Path XRO Subobjects .........................................5
2.2.1. IPv4 Point-to-Point Path subobject ....................... 5
2.2.2. IPv6 Point-to-Point Path subobject ....................... 9
2.3. Processing rules for the Path XRO subobjects ..............10
2.4. Path EXRS Subobject ........................................13
2.4.1. Processing Rules for the EXRS with Path subobject ....... 14
3. Security Considerations .....................................14
4. IANA Considerations .........................................14
4.1. New XRO subobject types ....................................14
4.2. New EXRS subobject types ...................................15
4.3. New RSVP error sub-codes....................................15
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5. Acknowledgements .............................................15
6. References ...................................................15
6.1. Normative References .................................15
6.2. Informative References ...............................16
1. Introduction
Path diversity is a well-known requirement from Service Providers.
Such diversity is required to ensure Label-Switched Path (LSPs)
may be established without sharing resources, thus greatly
reducing the probability of simultaneous connection failures.
When route computation for paths that need to be diverse is
performed at the LSP's source node, this requirement can be met by
a local decision at that node. However, there are scenarios when
route computations are performed by remote nodes, there is a need
for relevant diversity requirements to be communicated to those
nodes. These include (but are not limited to):
. LSPs with loose hops in the Explicit Route Object (ERO), e.g.
inter-domain LSPs.
. Generalized Multi-Protocol Label Switching (GMPLS) User-
Network Interface (UNI) where route computation may be
performed by the (server layer) core node [RFC4208];
[RFC4874] introduced a means of specifying nodes and resources to
be excluded from a route, using the eXclude Route Object (XRO) and
Explicit Exclusion Route Subobject (EXRS).
[RFC4874] facilitates the calculation of diverse routes for LSPs
based on known properties of those paths including addresses of
links and nodes traversed, and Shared Risk Link Groups (SRLGs) of
traversed links. This requires that these properties of the
path(s) from which diversity is required be known to the source
node which initiates signaling. However, there are circumstances
under which this may not be possible or desirable, including (but
not limited to):
. Exclusion of a path which does not originate, terminate or
traverse the source node signaling the diverse LSP, in which
case the addresses and SRLGs of the path from which diversity
is required are unknown to the source node.
. Exclusion of a path which, while known at the source node of
the diverse LSP, has incomplete or unavailable route
information, e.g. due to confidentiality of the path
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attributes. In other words, the scenario in which the reference
path is hosted by the source / requesting node but the
properties required to construct an XRO object are not known to
source / requesting node. Inter-domain and GMPLS overlay
networks may present such restrictions.
. If the source node knows the route of the reference path from
which diversity is required, it can use this information to
construct an XRO and send it in the path message during the
signaling of a diverse LSP. However, if the route of the
excluded path changes (e.g. due to re-optimization or failure
in the network), the source node would need to change the
diverse path to ensure that it remains diverse from the
excluded path. It is preferable to have this decision made by
the node that performed the path-calculation for the diverse
path. For example, in the case of GMPLS-UNI, it is better to
have such responsibility at the server layer as opposed to at
the client layer so that the diversity requirements are
transparent to the client layer. Furthermore, in all networking
scenarios, if the node performing the route computation/
expansion is aware of the diversity requirements of the two
paths, it may consider joint re-optimization of the diverse
paths.
This document addresses such scenarios and defines procedures
that may be used to exclude the route taken by a particular LSP,
or the routes taken by all LSPs belonging to a single tunnel.
Note that this diversity requirement is different from the
diversity requirements of path protection where both the
reference and diverse LSPs belong to the same tunnel. The
diversity requirements considered in this document do not require
that the paths in question belonging to the same tunnel or share
the same source or destination node.
The means by which the node calculating or expanding the route of
the signaled LSP discovers the route of the path(s) from which
the signaled LSP requires diversity are beyond the scope of this
document.
This document addresses only the exclusion of point-to-point
paths; point-to-multipoint paths will be addressed in a future
version.
If mutually diverse routes are desired for two LSPs belonging to
different tunnels, it is recommended that they be signaled with
XRO LSP subobjects referencing each other. The processing rules
specified in this document cover this case.
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2. RSVP-TE signaling extensions
This section describes the signaling extensions required to
address the aforementioned requirements. Specifically, this
document defines a new LSP subobject to be signaled in the
EXCLUDE_ROUTE object (XRO) and/ or Explicit Exclusion Route
Subobject (EXRS) defined in [RFC4874]. Inclusion of the LSP
subobject in any other RSVP object is not defined.
2.1. Terminology
In this document, the following terminology is adopted:
Excluded path: the path from which diversity is required.
Diverse LSP: the LSP being signaled with XRO/ EXRS containing the
path subobject referencing the excluded path(s).
Processing node: the node performing a path-calculation involving
an exclusion specified in an XRO or EXRS.
Destination node: in the context of an XRO, this is the
destination of the LSP being signaled. In the context of an EXRS,
the destination node is the last explicit node to which the loose
hop is expanded.
Penultimate node: in the context of an XRO, this is the
penultimate hop of the LSP being signaled. In the context of an
EXRS, the penultimate node is the penultimate node of the loose
hop undergoing expansion.
2.2. Path XRO Subobjects
New IPv4 and IPv6 Point-to-Point (P2P) Path XRO subobjects are
defined by this document as follows.
2.2.1. IPv4 Point-to-Point Path subobject
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 |Attribute Flags|Exclusion Flags|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel end point address |
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
L
The L-flag is used as for the other XRO subobjects defined
in [RFC4874].
0 indicates that the attribute specified MUST be excluded.
1 indicates that the attribute specified SHOULD be
avoided.
Type
IPv4 Point-to-Point Path subobject
(to be assigned by IANA; suggested value: 36).
Length
The length contains the total length of the subobject in
bytes, including the type and length fields. The length is
always 24.
Attribute Flags
The Attribute Flags are used to communicate desirable
attributes of the LSP being signaled. The following flags
are defined. None, all or multiple attribute flags MAY be
set within the same subobject.
0x01 = LSP ID to be ignored
This flag is used to indicate tunnel level exclusion.
Specifically, this flag is used to indicate that the
lsp-id field of the subobject is to be ignored and the
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exclusion applies to any LSP matching the rest of the
supplied FEC.
0x02 = Destination node exception
This flag is used to indicate that the destination node
of the LSP being signaled MAY be shared with the
excluded path even when this violates the exclusion
flags.
0x04 = Processing node exception
This flag is used to indicate that the processing node
MAY be shared with the excluded path even when this
violates the exclusion flags.
0x08 = Penultimate node exception
This flag is used to indicate that the penultimate node
of the LSP being signaled MAY be shared with the
excluded path even when this violates the exclusion
flags.
Exclusion Flags
The Exclusion-Flags are used to communicate desirable
types of exclusion. The following flags are defined.
0x01 = SRLG exclusion
This flag is used to indicate that the route of the
LSP being signaled is requested to be SRLG diverse
from the excluded path specified by the LSP
subobject.
0x02 = Node exclusion
This flag is used to indicate that the route of the
LSP being signaled is requested to be node diverse
from the excluded path specified by the LSP
subobject.
(Note: the meaning of this flag may be modified by
the value of the Attribute-flags.)
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0x04 = Link exclusion
This flag is used to indicate that the route of the
LSP being signaled is requested to be link diverse
from the path specified by the LSP subobject.
The remaining fields are as defined in [RFC3209].
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2.2.2. IPv6 Point-to-Point Path subobject
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 |Attribute Flags|Exclusion Flags|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 tunnel end point address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 tunnel end point address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 tunnel end point address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 tunnel end point address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address (cont.) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
L
The L-flag is used as for the other XRO subobjects defined
in [RFC4874].
0 indicates that the attribute specified MUST be excluded.
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1 indicates that the attribute specified SHOULD be
avoided.
Type
IPv6 Point-to-Point Path subobject
(to be assigned by IANA; suggested value: 37).
Length
The length contains the total length of the subobject in
bytes, including the type and length fields. The length is
always 48.
The Attribute Flags and Exclusion Flags are as defined for the
IPv4 Point-to-Point LSP XRO subobject.
The remaining fields are as defined in [RFC3209].
2.3. Processing rules for the Path XRO subobjects
XRO processing as described in [RFC4874] is unchanged.
If the processing node is the destination for the LSP being
signaled, it SHOULD NOT process a Path XRO subobject.
If the L-flag is not set, the processing node follows the
following procedure:
- The processing node MUST ensure that any route calculated for
the signaled LSP respects the requested exclusion flags with
respect to the excluded path referenced by the subobject,
including local resources.
- If the processing node fails to find a route that meets the
requested constraint, the processing node MUST return a PathErr
with the error code "Routing Problem" (24) and error sub-code
"Route blocked by Exclude Route" (67).
- If the excluded path referenced in the LSP subobject is
unknown to the processing node, the processing node SHOULD
ignore the LSP subobject in the XRO and SHOULD proceed with the
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signaling request. After sending the Resv for the signaled LSP,
the processing node SHOULD return a PathErr with the error code
"Notify Error" (25) and error sub-code "Route of XRO path
unknown" (value to be assigned by IANA, suggested value: 13)
for the signaled LSP.
If the L-flag is set, the processing node follows the following
procedure:
- The processing node SHOULD respect the requested exclusion
flags with respect to the excluded path as far as possible.
- If the processing node fails to find a route that meets the
requested constraint, it SHOULD proceed with signaling using a
suitable route that meets the constraint as far as possible.
After sending the Resv for the signaled LSP, it SHOULD return a
PathErr message with error code "Notify Error" (25) and error
sub-code "Failed to respect Exclude Route" (value: to be
assigned by IANA, suggest value: 14) to the source node.
- If the excluded path referenced in the LSP subobject is
unknown to the processing node, the processing node SHOULD
ignore the LSP subobject in the XRO and SHOULD proceed with the
signaling request. After sending the Resv for signaled LSP, the
processing node SHOULD return a PathErr message with the error
code "Notify Error" (25) and error sub-code "Route of XRO path
unknown" for the signaled LSP.
If, subsequent to the initial signaling of a diverse LSP:
- an excluded path referenced in the diverse LSP's XRO
subobject becomes known to the processing node (e.g. when the
excluded path is signaled), or
- A change in the excluded path becomes known to the processing
node,
the processing node SHOULD re-evaluate the exclusion and
diversity constraints requested by the diverse LSP to determine
whether they are still satisfied.
- If the requested exclusion constraints for the diverse LSP
are no longer satisfied and an alternative route for the
diverse LSP that can satisfy those constraints exists, the
processing node SHOULD send a PathErr message for the diverse
LSP with the error code "Notify Error" (25) and error sub-code
"Preferable path exists" (6). A source node receiving a PathErr
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message with this error code and sub-code combination MAY try
to reoptimize the diverse tunnel to the new compliant path.
- If the requested exclusion constraints for the diverse LSP
are no longer satisfied and no alternative path for the diverse
LSP that can satisfy those constraints exists, then:
o If the L-flag was not set in the original exclusion, the
processing node MUST send a PathErr message for the
diverse LSP with the error code "Routing Problem" (24) and
error sub-code "Route blocked by Exclude Route" (67). The
PSR flag SHOULD NOT be set.
o If the L-flag was set in the original exclusion, the
processing node SHOULD send a PathErr message for the
diverse LSP with the error code error code "Notify Error"
(25) and error sub-code "Failed to respect Exclude Route"
(value: to be assigned by IANA, suggest value: 14).
The following rules apply whether or not the L-flag is set:
- An XRO object MAY contain multiple path subobjects.
- As specified in [RFC4874], a node receiving a Path message
carrying an XRO MAY reject the message if the XRO is too large
or complicated for the local implementation or the rules of
local policy. In this case, the node MUST send a PathErr
message with the error code "Routing Error" (24) and error sub-
code "XRO Too Complex" (68). A source node receiving this
error code/sub-code combination MAY reduce the complexity of
the XRO or route around the node that rejected the XRO.
- A source node receiving a PathErr message with the error code
"Notify Error" (25) and error sub-codes "Route of XRO path
unknown" or "Failed to respect Exclude Route" MAY take no
action.
- The attribute-flags affect the processing of the XRO subobject
as follows:
o When the "LSP ID to be ignored" flag is set, the
processing node MUST calculate a route based on exclusions
from the routes of all known LSPs matching the tunnel-id,
source, destination and extended tunnel-id specified in
the subobject. When this flag is not set, the lsp-id is
not ignored and the exclusion applies only to the
specified LSP (i.e., LSP level exclusion).
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o When the "destination node exception" flag is not set, the
exclusion flags SHOULD also be respected for the
destination node.
o When the "processing node exception" flag is not set, the
exclusion flags SHOULD also be respected for the
processing node.
o When the "penultimate node exception" flag is not set, the
exclusion flags SHOULD also be respected for the
penultimate node.
2.4. Path EXRS Subobject
[RFC4874] defines the EXRS ERO subobject. An EXRS is used to
identify abstract nodes or resources that must not or should not
be used on the path between two inclusive abstract nodes or
resources in the explicit route. An EXRS contains one or more
subobjects of its own, called EXRS subobjects [RFC4874].
An EXRS MAY include an IPv4 Point-to-Point (P2P) Path subobject
as specified in section 2.2.1. In this case, the EXRS format
would be 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 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| Type | Length |Attribute Flags|Exclusion Flags|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel end point address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 tunnel sender address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Must Be Zero | LSP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The meaning of respective fields in EXRS header is as defined in
[RFC4874]. The meaning of respective fields in IPv4 P2P Path
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subobject is as defined earlier in this document. This is with
the exceptions that:
- The processing node exception applies to the node processing
the ERO.
- If the L bit in the ERO header is not set (ERO.L = 0), the
IPv4 P2P Path subobject is processed against the path(s) for
which the processing node is a source, destination or transit
node.
- The penultimate node exception applies to the penultimate node
of the loose hop. This flag is only processed if the ERO.L bit
is set, i.e. in the loose ERO hop case.
- The destination node exception applies to the last explicit
node to which the loose hop is expanded. This flag is only
processed if ERO.L bit is set, i.e., in the loose ERO hop case.
2.4.1. Processing Rules for the EXRS with Path subobject
The processing rules for the EXRS object are unchanged from
[RFC4874]. When the EXRS contains one or more Path subobject(s),
the processing rules specified in Section 2.3 apply to the node
processing the ERO with the EXRS subobject.
The EXRS scope is limited to the loose hop in which the EXRS
appears. If loose-hop expansion results in the creation of
another loose-hop in the outgoing ERO, the processing node MAY
include the EXRS in the newly-created loose hop for further
processing by downstream nodes.
3. Security Considerations
This document does not introduce any additional security issues
above those identified in [RFC5920], [RFC2205], [RFC3209],
[RFC3473] and [RFC4874].
4. IANA Considerations
4.1. New XRO subobject types
IANA registry: RSVP PARAMETERS
Subsection: Class Names, Class Numbers, and Class Types
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This document introduces two new subobjects for the EXCLUDE_ROUTE
object [RFC4874], C-Type 1.
Subobject Type
Subobject Description
--------------
---------------------
To be assigned by IANA IPv4 P2P Path subobject
(suggested value: 36)
To be assigned by IANA IPv6 P2P Path subobject
(suggested value: 37)
4.2. New EXRS subobject types
The IPv4 and IPv6 P2P Path subobjects are also defined as new
EXRS subobjects.
4.3. New RSVP error sub-codes
IANA registry: RSVP PARAMETERS
Subsection: Error Codes and Globally-Defined Error Value Sub-
Codes
For Error Code "Notify Error" (25) (see [RFC3209]) the following
sub-codes are defined.
Sub-code Value
-------- -----
Route of XRO path unknown To be assigned by IANA.
Suggested Value: 13.
Failed to respect Exclude Route To be assigned by IANA.
Suggested Value: 14.
5. Acknowledgements
The authors would like to thank Luyuan Fang and Walid Wakim for
their review comments.
6. References
6.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[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.
[RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions", RFC 3473, January
2003.
[RFC4874] Lee, CY., Farrel, A., and S. De Cnodder, "Exclude
Routes - Extension to Resource ReserVation Protocol-
Traffic Engineering (RSVP-TE)", RFC 4874, April 2007.
6.2. Informative References
[RFC4208] Swallow, G., Drake, J., Ishimatsu, H., and Y. Rekhter,
"Generalized Multiprotocol Label Switching (GMPLS)
User-Network Interface (UNI): Resource ReserVation
Protocol-Traffic Engineering (RSVP-TE) Support for the
Overlay Model", RFC 4208, October 2005.
[RFC2209] Braden, R. and L. Zhang, "Resource ReSerVation Protocol
(RSVP) -- Version 1 Message Processing Rules", RFC
2209, September 1997.
[RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
Networks", RFC 5920, July 2010.
Authors' Addresses
Zafar Ali
Cisco Systems.
Email: zali@cisco.com
George Swallow
Cisco Systems
swallow@cisco.com
Clarence Filsfils
Cisco Systems, Inc.
cfilsfil@cisco.com
Ali, Swallow, Filsfils, et al Expires July 2013 [Page 16]
Internet Draft draft-ietf-ccamp-lsp-diversity-01.txt
Matt Hartley
Cisco Systems
Email: mhartley@cisco.com
Ori Gerstel
Cisco Systems
ogerstel@cisco.com
Gabriele Maria Galimberti
Cisco Systems
ggalimbe@cisco.com
Kenji Kumaki
KDDI Corporation
Email: ke-kumaki@kddi.com
Rudiger Kunze
Deutsche Telekom AG
Ruediger.Kunze@telekom.de
Julien Meuric
France Telecom Orange
Email: julien.meuric@orange.com
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