draft-ietf-ccamp-inter-domain-recovery-analysis-01.txt   draft-ietf-ccamp-inter-domain-recovery-analysis-02.txt 
Network Working Group Tomonori Takeda, Ed. Network Working Group Tomonori Takeda, Ed.
Internet Draft NTT Internet Draft NTT
Intended Status: Informational Yuichi Ikejiri Intended Status: Informational Yuichi Ikejiri
Expires: January 2008 NTT Communications Expires: March 2008 NTT Communications
Adrian Farrel Adrian Farrel
Old Dog Consulting Old Dog Consulting
Jean-Philippe Vasseur Jean-Philippe Vasseur
Cisco Systems, Inc. Cisco Systems, Inc.
September 2007
Analysis of Inter-domain Label Switched Path (LSP) Recovery Analysis of Inter-domain Label Switched Path (LSP) Recovery
draft-ietf-ccamp-inter-domain-recovery-analysis-01.txt draft-ietf-ccamp-inter-domain-recovery-analysis-02.txt
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
skipping to change at page 2, line 12 skipping to change at page 2, line 12
presents various diverse LSP setup schemes based on existing presents various diverse LSP setup schemes based on existing
functional elements. functional elements.
Table of Contents Table of Contents
1. Introduction...................................................2 1. Introduction...................................................2
1.1 Terminology...................................................3 1.1 Terminology...................................................3
1.2 Domain........................................................4 1.2 Domain........................................................4
1.3 Document Scope................................................4 1.3 Document Scope................................................4
1.4 Note on Other Recovery Techniques.............................5 1.4 Note on Other Recovery Techniques.............................5
1.5 Signaling Options.............................................5 1.5 Signaling Options.............................................6
2. Diversity in Multi-domain Networks.............................5 2. Diversity in Multi-domain Networks.............................6
2.1 Multi-domain Network Topology.................................6 2.1 Multi-domain Network Topology.................................6
2.2 Note on Domain Diversity......................................7 2.2 Note on Domain Diversity......................................8
3. Factors to Consider............................................8 3. Factors to Consider............................................8
3.1 Scalability versus Optimality.................................8 3.1 Scalability versus Optimality.................................8
3.2 Key Concepts..................................................8 3.2 Key Concepts..................................................9
4. Diverse LSP Setup Schemes without Confidentiality.............10 4. Diverse LSP Setup Schemes without Confidentiality.............11
4.1 Management Configuration.....................................10 4.1 Management Configuration.....................................11
4.2 Head-end Path Computation (with multi-domain visibility).....10 4.2 Head-end Path Computation (with multi-domain visibility).....11
4.3 Per-domain Path Computation..................................10 4.3 Per-domain Path Computation..................................11
4.3.1 Sequential Path Computation................................11 4.3.1 Sequential Path Computation................................12
4.3.2 Simultaneous Path Computation..............................12 4.3.2 Simultaneous Path Computation..............................12
4.4 Inter-domain Collaborative Path Computation..................13 4.4 Inter-domain Collaborative Path Computation..................13
4.4.1 Sequential Path Computation................................13 4.4.1 Sequential Path Computation................................14
4.4.2 Simultaneous Path Computation..............................14 4.4.2 Simultaneous Path Computation..............................14
5. Diverse LSP Setup Schemes with Confidentiality................14 5. Diverse LSP Setup Schemes with Confidentiality................15
5.1 Management Configuration.....................................15 5.1 Management Configuration.....................................16
5.2 Head-end Path Computation (with multi-domain visibility).....15 5.2 Head-end Path Computation (with multi-domain visibility).....16
5.3 Per-Domain Path Computation..................................15 5.3 Per-Domain Path Computation..................................16
5.3.1 Sequential Path Computation................................15 5.3.1 Sequential Path Computation................................16
5.3.2 Simultaneous Path Computation..............................16 5.3.2 Simultaneous Path Computation..............................17
5.4 Inter-domain Collaborate Path Computation....................16 5.4 Inter-domain Collaborative Path Computation..................17
5.4.1 Sequential Path Computation................................16 5.4.1 Sequential Path Computation................................17
5.4.2 Simultaneous Path Computation..............................17 5.4.2 Simultaneous Path Computation..............................18
6. Network Topology Specific Considerations......................18 6. Network Topology Specific Considerations......................18
7. Addressing Considerations.....................................18 7. Addressing Considerations.....................................19
8. Note on SRLG Diversity........................................18 8. Note on SRLG Diversity........................................19
9. Security Considerations.......................................18 9. Security Considerations.......................................19
10. References...................................................19 10. References...................................................20
10.1 Normative References........................................19 10.1 Normative References........................................20
10.2 Informative References......................................19 10.2 Informative References......................................20
11. Acknowledgments..............................................21 11. Acknowledgments..............................................22
12. Authors' Addresses...........................................21 12. Authors' Addresses...........................................22
Intellectual Property Consideration..............................22 Intellectual Property Consideration..............................23
Full Copyright Statement.........................................22 Full Copyright Statement.........................................23
1. Introduction 1. Introduction
This document analyzes various schemes to realize Multiprotocol Label This document analyzes various schemes to realize Multiprotocol Label
Switching (MPLS) and Generalized MPLS (GMPLS) Label Switched Path Switching (MPLS) and Generalized MPLS (GMPLS) Label Switched Path
(LSP) recovery in multi-domain networks based on the existing (LSP) recovery in multi-domain networks based on the existing
framework for multi-domain LSPs. framework for multi-domain LSPs.
The main focus for this document is on establishing end-to-end The main focus for this document is on establishing end-to-end
diverse Traffic Engineering (TE) LSPs in multi-domain networks. It diverse Traffic Engineering (TE) LSPs in multi-domain networks. It
skipping to change at page 3, line 25 skipping to change at page 3, line 25
[RFC4726] that provides a framework for inter-domain Label Switched [RFC4726] that provides a framework for inter-domain Label Switched
Path (LSP) setup, and [RFC4427] that provides terminology for LSP Path (LSP) setup, and [RFC4427] that provides terminology for LSP
recovery. recovery.
The following are several key terminologies used within this The following are several key terminologies used within this
document. document.
- Domain: See [RFC4726]. A domain is considered to be any - Domain: See [RFC4726]. A domain is considered to be any
collection of network elements within a common sphere of address collection of network elements within a common sphere of address
management or path computational responsibility. Note that nested management or path computational responsibility. Note that nested
domains continue to be out of scope. domains continue to be out of scope. Section 1.2 provides some more
details.
- Working LSP: See [RFC4427]. The working LSP transports normal user - Working LSP: See [RFC4427]. The working LSP transports normal user
traffic. Note that the term LSP and TE LSP will be used traffic. Note that the term LSP and TE LSP will be used
interchangeably. interchangeably.
- Recovery LSP: See [RFC4427]. The recovery LSP transports normal - Recovery LSP: See [RFC4427]. The recovery LSP transports normal
user traffic when the working LSP fails. The recovery LSP may user traffic when the working LSP fails. The recovery LSP may
transport user traffic even when the working LSP is transporting transport user traffic even when the working LSP is transporting
normal user traffic (e.g., 1+1 protection). In such a scenario, normal user traffic (e.g., 1+1 protection). In such a scenario,
the recovery LSP is sometimes referred to as a protecting LSP. the recovery LSP is sometimes referred to as a protecting LSP.
skipping to change at page 4, line 20 skipping to change at page 4, line 20
IGP areas and Autonomous Systems. A network accessed over the IGP areas and Autonomous Systems. A network accessed over the
Generalized Multiprotocol Label Switching (GMPLS) User-to-Network Generalized Multiprotocol Label Switching (GMPLS) User-to-Network
Interface (UNI) [RFC4208] and a Layer One Virtual Private Network Interface (UNI) [RFC4208] and a Layer One Virtual Private Network
(L1VPN) [RFC4847] are special cases of multi-domain networks. (L1VPN) [RFC4847] are special cases of multi-domain networks.
Example objectives of domain usage include administrative separation, Example objectives of domain usage include administrative separation,
scalability, and forming protection domains. scalability, and forming protection domains.
As described in [RFC4726], there could be TE parameters (such as As described in [RFC4726], there could be TE parameters (such as
color and priority) whose meanings are specific to each domain. In color and priority) whose meanings are specific to each domain. In
such a scenarios, mapping functions could be performed based on such scenarios, mapping functions could be performed based on policy
policy agreements between domain administrators. agreements between domain administrators.
1.3 Document Scope 1.3 Document Scope
This document analyzes various schemes to realize Multiprotocol Label This document analyzes various schemes to realize Multiprotocol Label
Switching (MPLS) and Generalized MPLS (GMPLS) LSP recovery in multi- Switching (MPLS) and Generalized MPLS (GMPLS) LSP recovery in multi-
domain networks based on the existing framework for multi-domain LSP domain networks based on the existing framework for multi-domain LSP
setup [RFC4726]. setup [RFC4726]. Note that this document does not intend to prevent
development of additional techniques where appropriate (i.e.,
additional to ones described in this document, which are based on the
existing framework described in [RFC4726]). In other words, this
document is informational and intends to show how the existing
framework can be applied with specific procedures described in this
document and the documents referred to by this document.
There are various recovery techniques for LSPs. For TE LSPs, major There are various recovery techniques for LSPs. For TE LSPs, major
techniques are end-to-end recovery [RFC4872], local protection such techniques are end-to-end recovery [RFC4872], local protection such
as Fast Reroute (FRR) [RFC4090] (in packet switching environments), as Fast Reroute (FRR) [RFC4090] (in packet switching environments),
and segment recovery [RFC4873] (in GMPLS). and segment recovery [RFC4873] (in GMPLS).
In this version of the document the main focus is the analysis of In this document the main focus is the analysis of diverse TE LSP
diverse TE LSP (hereafter LSP) setup schemes, which can (hereafter LSP) setup schemes (path computation and signaling
advantageously used in the context of end-to-end recovery. This aspects), which can advantageously be used in the context of end-to-
document presents various diverse LSP setup schemes by combining end recovery. This document presents various diverse LSP setup
various functional elements. Details of maintenance of diverse LSPs, schemes by combining various functional elements. In particular,
such as re-optimization and OAM, are beyond the scope of this Section 5.5 of [RFC4726] describes some analysis of diverse LSPs in
document. multi-domain networks, and this document provides more detailed
analysis based on that content.
Note that the comparative evaluation of these various schemes is out
of scope for this document, and should be described in separate
applicability documents.
[RFC4105] and [RFC4216] describe requirements for diverse LSPs. There [RFC4105] and [RFC4216] describe requirements for diverse LSPs. There
could be various types of diversity, and this document focuses on could be various types of diversity, and this document focuses on
node/link/SRLG diversity. Note that domain diversity (that is, the node/link/SRLG diversity.
selection of paths that have only the ingress and egress domains in
common) is discussed in Section 2.2.
Based on the service grade, both the working LSP and the recovery LSP Based on the service grade, both the working LSP and the recovery LSP
may be established at the time of service establishment (e.g., may be established at the time of service establishment (e.g.,
service requiring high resiliency). Alternatively, the recovery LSP service requiring high resiliency). Alternatively, the recovery LSP
may be added later due to a change in the grade of the service. may be added later due to a change in the grade of the service. This
document covers both scenarios. Also, there may or may not be
confidentiality requirements among domains. This document covers both
scenarios. Section 3.2 describes more details on confidentiality.
Also, the recovery LSP may be used for 1+1 protection, 1:1 Specific assumptions made in this problem space are described in
Section 2.
Note that the recovery LSP may be used for 1+1 protection, 1:1
protection, or shared mesh restoration. However, ways to compute protection, or shared mesh restoration. However, ways to compute
diverse paths, and the signaling of these TE LSPs are common across diverse paths, and the signaling of these TE LSPs are common across
all uses, and these topics are the main scope of this document. all uses, and these topics are the main scope of this document.
Section 5.5 of [RFC4726] describes some analysis of diverse LSPs in Also, note that diverse LSPs may be used for various purposes, in
multi-domain networks, and this document provides more detailed addition to recovery. An example is for load-balancing, so as to
analysis based on that content. limit the traffic disruption to a portion of the traffic flow in case
of a single network element failure. This document does not preclude
use of diverse LSP setup schemes for those purposes.
Note that diverse LSPs may be used for various purposes, in addition The following are beyond the scope of this document.
to recovery. An example is for load-balancing, so as to limit the
traffic disruption to a portion of the traffic flow in case of a - Analysis of recovery techniques other than link/node/SRLG diverse
single network element failure. This document does not preclude use LSPs (see Section 1.4).
of diverse LSP setup schemes for those purposes. - Details of maintenance of diverse LSPs, such as re-optimization and
OAM.
- Comparative evaluation of various diverse LSP setup schemes
mentioned in this document.
1.4 Note on Other Recovery Techniques 1.4 Note on Other Recovery Techniques
Fast Reroute and segment recovery in multi-domain networks are Fast Reroute and segment recovery in multi-domain networks are
described in Section 5.4 of [RFC4726], and a more detailed analysis described in Section 5.4 of [RFC4726], and a more detailed analysis
is provided in Section 5 of [inter-domain-rsvp]. is provided in Section 5 of [inter-domain-rsvp]. This document does
not cover any additional analysis for Fast ReRoute and segment
recovery in multi-domain networks.
Also, the recovery type of an LSP or service may change at a domain Also, the recovery type of an LSP or service may change at a domain
boundary. That is, the recovery type could remain the same within one boundary. That is, the recovery type could remain the same within one
domain, but might be different in the next domain. This may be due to domain, but might be different in the next domain. This may be due to
the capabilities of each domain, administrative policies, or to the capabilities of each domain, administrative policies, or to
topology limitations. An example is where protection at the domain topology limitations. An example is where protection at the domain
boundary is provided by link protection on the inter-domain link(s), boundary is provided by link protection on the inter-domain link(s),
but where protection within each domain is achieved through segment but where protection within each domain is achieved through segment
recovery. This mixture of protection techniques is beyond the scope recovery. This mixture of protection techniques is beyond the scope
of this document. of this document.
Domain diversity (that is, the selection of paths that have only the
ingress and egress domains in common) may be considered as one form
of diversity in multi-domain networks, but this is beyond the scope
of this document (see Section 2.2).
1.5 Signaling Options 1.5 Signaling Options
There are three signaling options for establishing inter-domain TE There are three signaling options for establishing inter-domain TE
LSPs: nesting, contiguous LSPs, and stitching [RFC4726]. The LSPs: nesting, contiguous LSPs, and stitching [RFC4726]. The
description in this document of diverse LSP setup is agnostic in description in this document of diverse LSP setup is agnostic in
relation to the signaling option used, unless otherwise specified. relation to the signaling option used, unless otherwise specified.
Note that signaling option-specific considerations for Fast Reroute Note that signaling option-specific considerations for Fast Reroute
and segment recovery are described in Section 5 of [inter-domain- and segment recovery are described in Section 5 of [inter-domain-
rsvp]. rsvp].
skipping to change at page 7, line 33 skipping to change at page 8, line 7
beyond the scope of this document. beyond the scope of this document.
Furthermore, the working LSP and the recovery LSP may or may not be Furthermore, the working LSP and the recovery LSP may or may not be
routed along the same set of domains in the same order. In this routed along the same set of domains in the same order. In this
document, we assume that the working LSP and recovery LSP follow the document, we assume that the working LSP and recovery LSP follow the
same set of domains in the same order (via configuration, policy or same set of domains in the same order (via configuration, policy or
some external mechanism). That is, we assume that the domain mesh some external mechanism). That is, we assume that the domain mesh
topology is reduced to a linear domain topology for each pair of topology is reduced to a linear domain topology for each pair of
working and recovery LSPs. working and recovery LSPs.
In summary,
- There is no assumption about the multi-domain network topology. For
example, there could be more than two domain boundary nodes or
inter-domain links (links connecting a pair of domain boundary
nodes belonging to different domains).
- However, there is an assumption that under such a network topology,
the set of domains that the working LSP and the recovery LSP follow
must be the same and pre-configured.
- Domain re-entry is not considered.
2.2 Note on Domain Diversity 2.2 Note on Domain Diversity
As described in Section 1.3, domain diversity means the selection of As described in Section 1.4, domain diversity means the selection of
paths that have only the ingress and egress domains in common. This paths that have only the ingress and egress domains in common. This
may provide enhanced resilience against failures, and is a way to may provide enhanced resilience against failures, and is a way to
ensure path diversity for most of the path of the LSP. ensure path diversity for most of the path of the LSP.
In Section 2.1 we assumed that the working LSP and the recovery LSP In Section 2.1 we assumed that the working LSP and the recovery LSP
follow the same set of domains in the same order. Under this follow the same set of domains in the same order. Under this
assumption, domain diversity cannot be achieved. However, by relaxing assumption, domain diversity cannot be achieved. However, by relaxing
this assumption, domain diversity could be achieved, e.g., by either this assumption, domain diversity could be achieved, e.g., by either
of the following schemes. of the following schemes.
skipping to change at page 9, line 20 skipping to change at page 10, line 4
computation computation
- Per domain path computation - Per domain path computation
In this scheme, a path is computed domain by domain as LSP In this scheme, a path is computed domain by domain as LSP
signaling progresses through the network. This scheme requires signaling progresses through the network. This scheme requires
ERO expansion in each domain. The case for unprotected LSPs under ERO expansion in each domain. The case for unprotected LSPs under
this scheme is covered in [inter-domain-pd]. this scheme is covered in [inter-domain-pd].
- Inter-domain collaborative path computation - Inter-domain collaborative path computation
In this scheme, path computation is typically done before In this scheme, path computation is typically done before
signaling. This scheme typically uses communication between signaling. This scheme typically uses communication between
cooperating path computation elements (PCEs) [RFC4655]. An cooperating path computation elements (PCEs) [RFC4655]. An
example of such a scheme is Backward Recursive Pause Computation example of such a scheme is Backward Recursive Path Computation
(BRPC) [brpc]. The use of BRPC for unprotected LSPs under this (BRPC) [brpc]. The use of BRPC for unprotected LSPs under this
scheme is covered in [brpc]. scheme is covered in [brpc].
Note that these are path computation techniques. It is also Note that these are path computation techniques. It is also
possible to obtain a path via management configuration, or head-end possible to obtain a path via management configuration, or head-end
path computation (with multi-domain visibility). This is discussed path computation (with multi-domain visibility). This is discussed
in Sections 4 and 5. in Sections 4 and 5.
Note also that it is possible to combine multiple path computation Note also that it is possible to combine multiple path computation
techniques (including using a different technique for the working techniques (including using a different technique for the working
skipping to change at page 12, line 8 skipping to change at page 12, line 42
In order that the computation noted above can be performed, each In order that the computation noted above can be performed, each
computation point must be aware of the path of the working LSP. computation point must be aware of the path of the working LSP.
This information can be supplied in the XRO included in the Path This information can be supplied in the XRO included in the Path
message for recovery LSP. The XRO lists nodes, links and SRLGs that message for recovery LSP. The XRO lists nodes, links and SRLGs that
must be avoided by the LSP being signaled, and its contents are must be avoided by the LSP being signaled, and its contents are
copied from the RRO of the working LSP. copied from the RRO of the working LSP.
This scheme cannot guarantee to establish diverse LSPs (even if they This scheme cannot guarantee to establish diverse LSPs (even if they
could exist) because the first LSP is established without could exist) because the first LSP is established without
consideration of the need for a diverse recovery LSP. Crankback consideration of the need for a diverse recovery LSP. Crankback
[crankback] may be used in combination with this scheme in order to [RFC4920] may be used in combination with this scheme in order to
improve the possibility of successful diverse LSP setup. Furthermore, improve the possibility of successful diverse LSP setup. Furthermore,
re-optimization of the working LSP and the recovery LSP may be used re-optimization of the working LSP and the recovery LSP may be used
to achieve fully diverse paths. to achieve fully diverse paths.
Note that even if a solution is found, the degree of optimality of Note that even if a solution is found, the degree of optimality of
the solution (i.e., of the set of diverse TE LSPs) might not be the solution (i.e., of the set of diverse TE LSPs) might not be
maximal. maximal.
4.3.2 Simultaneous Path Computation 4.3.2 Simultaneous Path Computation
skipping to change at page 13, line 9 skipping to change at page 13, line 41
and to return is to the head-end in the Resv message. When and to return is to the head-end in the Resv message. When
signaling the recovery LSP, the content of the ERO is copied from signaling the recovery LSP, the content of the ERO is copied from
this object. this object.
Protocol mechanisms to achieve these signaling features are not Protocol mechanisms to achieve these signaling features are not
currently available. The definition of protocol extensions is currently available. The definition of protocol extensions is
beyond the scope of this document. beyond the scope of this document.
This scheme also cannot guarantee to establish diverse LSPs (even if This scheme also cannot guarantee to establish diverse LSPs (even if
they could exist) if there are more than two domain boundary nodes they could exist) if there are more than two domain boundary nodes
out of each domain. Crankback [crankback] may also be used in out of each domain. Crankback [RFC4920] may also be used in
combination with this scheme to improve the chances of success. combination with this scheme to improve the chances of success.
Note that even if a solution is found, the degree of optimality of Note that even if a solution is found, the degree of optimality of
the solution (i.e., of the set of diverse TE LSPs) might not be the solution (i.e., of the set of diverse TE LSPs) might not be
maximal. maximal.
4.4 Inter-domain Collaborative Path Computation 4.4 Inter-domain Collaborative Path Computation
Section 3.4 of [RFC4726] describes this approach, and [brpc] provides Section 3.4 of [RFC4726] describes this approach, and [brpc] provides
detail of Backward Recursive Path Computation which is a detail of Backward Recursive Path Computation which is a
skipping to change at page 16, line 44 skipping to change at page 17, line 29
- Alternatively, information identifying the working LSP is included - Alternatively, information identifying the working LSP is included
in the Path message for the recovery LSP, and the domain boundary in the Path message for the recovery LSP, and the domain boundary
node consults the entity which computed the path of the recovery node consults the entity which computed the path of the recovery
LSP (i.e., domain boundary node or PCE), so as to obtain the path LSP (i.e., domain boundary node or PCE), so as to obtain the path
of the recovery LSP. This requires that the entity which computed of the recovery LSP. This requires that the entity which computed
the path of the recovery LSP is temporarily stateful. An example of the path of the recovery LSP is temporarily stateful. An example of
such information is the Association Object [RFC4872]. Detailed such information is the Association Object [RFC4872]. Detailed
protocol specifications are beyond the scope of this document. protocol specifications are beyond the scope of this document.
5.4 Inter-domain Collaborate Path Computation 5.4 Inter-domain Collaborative Path Computation
5.4.1 Sequential Path Computation 5.4.1 Sequential Path Computation
Route exclusion using the XRO [PCEP-XRO] in combination with the path Route exclusion using the XRO [PCEP-XRO] in combination with the path
key [conf-segment] can be requested in PCEP [PCEP] and this can be key [conf-segment] can be requested in PCEP [PCEP] and this can be
used to compute the path of a recovery LSP after the path of the used to compute the path of a recovery LSP after the path of the
working LSP has been determined. Details are as follows. working LSP has been determined. Details are as follows.
The working LSP is computed as described in [brpc] with the help of The working LSP is computed as described in [brpc] with the help of
path key [conf-segment], and may be immediately established. It is path key [conf-segment], and may be immediately established. It is
skipping to change at page 20, line 50 skipping to change at page 21, line 34
[inter-domain-pd] Vasseur JP., Ed., and Ayyangar A., Ed., "A Per- [inter-domain-pd] Vasseur JP., Ed., and Ayyangar A., Ed., "A Per-
domain path computation method for establishing domain path computation method for establishing
Inter-domain Traffic Engineering (TE) Label Inter-domain Traffic Engineering (TE) Label
Switched Paths (LSPs)", draft-ietf-ccamp-inter- Switched Paths (LSPs)", draft-ietf-ccamp-inter-
domain-pd-path-comp, work in progress. domain-pd-path-comp, work in progress.
[brpc] Vasseur, JP., Ed., "A Backward Recursive [brpc] Vasseur, JP., Ed., "A Backward Recursive
PCE-based Computation (BRPC) procedure to compute PCE-based Computation (BRPC) procedure to compute
shortest inter-domain Traffic Engineering Label shortest inter-domain Traffic Engineering Label
Switched Path", draft-ietf-pce-brpc, work in Switched Paths", draft-ietf-pce-brpc, work in
progress. progress.
[PCEP-XRO] Oki, E., and A. Farrel, "Extensions to the Path [PCEP-XRO] Oki, E., and A. Farrel, "Extensions to the Path
Computation Element Communication Protocol (PCEP) Computation Element Communication Protocol (PCEP)
for Route Exclusions", draft-ietf-pce-pcep-xro, for Route Exclusions", draft-ietf-pce-pcep-xro,
work in progress. work in progress.
[PCEP] Vasseur, JP., Ed., and Le Roux, JL., Ed., "Path [PCEP] Vasseur, JP., Ed., and Le Roux, JL., Ed., "Path
Computation Element (PCE) communication Protocol Computation Element (PCE) communication Protocol
(PCEP)", draft-ietf-pce-pcep, work in progress. (PCEP)", draft-ietf-pce-pcep, work in progress.
[conf-segment] Bradford, R., Ed., "Preserving Topology [conf-segment] Bradford, R., Ed., "Preserving Topology
Confidentiality in Inter-Domain Path Computation Confidentiality in Inter-Domain Path Computation
using a key based mechanism ", draft-ietf-pce- using a key based mechanism ", draft-ietf-pce-
path-key, work in progress. path-key, work in progress.
[crankback] Farrel, A., Ed., "Crankback Signaling Extensions [RFC4920] Farrel, A., Ed., "Crankback Signaling Extensions
for MPLS Signaling", draft-ietf-ccamp-crankback, for MPLS and GMPLS RSVP-TE ", RFC 4920,
work in progress. July 2007.
[RFC4206] Kompella, K. and Y. Rekhter, "Label Switched [RFC4206] Kompella, K. and Y. Rekhter, "Label Switched
Paths (LSP) Hierarchy with Generalized Multi- Paths (LSP) Hierarchy with Generalized Multi-
Protocol Label Switching (GMPLS) Traffic Protocol Label Switching (GMPLS) Traffic
Engineering (TE)", RFC 4206, October 2005. Engineering (TE)", RFC 4206, October 2005.
[LSP-stitch] Ayyangar, A., Kompella, K., Vasseur, JP., and [LSP-stitch] Ayyangar, A., Kompella, K., Vasseur, JP., and
A. Farrel, "Label Switched Path Stitching with A. Farrel, "Label Switched Path Stitching with
Generalized Multiprotocol Label Switching Traffic Generalized Multiprotocol Label Switching Traffic
Engineering (GMPLS TE)", draft-ietf-ccamp-lsp- Engineering (GMPLS TE)", draft-ietf-ccamp-lsp-
stitching, work in progress. stitching, work in progress.
[security-fw] Fang, L., " Security Framework for MPLS and GMPLS [security-fw] Fang, L., " Security Framework for MPLS and GMPLS
Networks", draft-fang-mpls-gmpls-security- Networks", draft-fang-mpls-gmpls-security-
Framework, work in progress. Framework, work in progress.
11. Acknowledgments 11. Acknowledgments
Authors would like to thank Eiji Oki, Ichiro Inoue, and Kazuhiro Authors would like to thank Eiji Oki, Ichiro Inoue, Kazuhiro
Fujihara for valuable comments. Fujihara, Dimitri Papadimitriou and Meral Shirazipour for valuable
comments.
12. Authors' Addresses 12. Authors' Addresses
Tomonori Takeda Tomonori Takeda
NTT Network Service Systems Laboratories, NTT Corporation NTT Network Service Systems Laboratories, NTT Corporation
3-9-11, Midori-Cho 3-9-11, Midori-Cho
Musashino-Shi, Tokyo 180-8585 Japan Musashino-Shi, Tokyo 180-8585 Japan
Email : takeda.tomonori@lab.ntt.co.jp Email : takeda.tomonori@lab.ntt.co.jp
Yuichi Ikejiri Yuichi Ikejiri
 End of changes. 30 change blocks. 
72 lines changed or deleted 105 lines changed or added

This html diff was produced by rfcdiff 1.34. The latest version is available from http://tools.ietf.org/tools/rfcdiff/