draft-ietf-pce-disco-proto-ospf-05.txt   draft-ietf-pce-disco-proto-ospf-06.txt 
Network Working Group J.L. Le Roux (Editor) Network Working Group J.L. Le Roux (Editor)
Internet Draft France Telecom Internet Draft France Telecom
Intended Status: Standards Track Intended Status: Standard Track
Expires: November 2007 J.P. Vasseur (Editor) Expires: December 2007 J.P. Vasseur (Editor)
Cisco System Inc. Cisco System Inc.
Yuichi Ikejiri Yuichi Ikejiri
NTT Communications NTT Communications
Raymond Zhang Raymond Zhang
BT Infonet BT Infonet
OSPF protocol extensions for Path Computation Element (PCE) Discovery OSPF protocol extensions for Path Computation Element (PCE) Discovery
draft-ietf-pce-disco-proto-ospf-05.txt draft-ietf-pce-disco-proto-ospf-06.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
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"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
Table of Contents Table of Contents
1. Terminology.................................................3 1. Terminology.................................................3
2. Introduction................................................4 2. Introduction................................................4
3. Overview....................................................5 3. Overview....................................................5
3.1. PCE Information.............................................5 3.1. PCE Information.............................................5
3.2. PCE Discovery Information...................................5 3.2. PCE Discovery Information...................................5
3.2.1. PCE Congestion Information..................................6 3.2.1. PCE Overload Information....................................6
3.3. Flooding Scope..............................................6 3.3. Flooding Scope..............................................6
4. OSPF Extensions.............................................6 4. OSPF Extensions.............................................6
4.1. The OSPF PCED TLV...........................................6 4.1. The OSPF PCED TLV...........................................6
4.1.1. PCE-ADDRESS Sub-TLV.........................................8 4.1.1. PCE-ADDRESS Sub-TLV.........................................8
4.1.2. PATH-SCOPE Sub-TLV..........................................8 4.1.2. PATH-SCOPE Sub-TLV..........................................8
4.1.3. PCE-DOMAIN Sub-TLV.........................................10 4.1.3. PCE-DOMAIN Sub-TLV.........................................10
4.1.4. NEIG-PCE-DOMAIN Sub-TLV....................................11 4.1.4. NEIG-PCE-DOMAIN Sub-TLV....................................11
4.1.5. PCE-CAP-FLAGS Sub-TLV......................................12 4.1.5. PCE-CAP-FLAGS Sub-TLV......................................12
4.1.6. The CONGESTION Sub-TLV.....................................14 4.1.6. The OVERLOAD Sub-TLV.......................................14
5. Elements of Procedure......................................14 5. Elements of Procedure......................................14
5.1. CONGESTION sub-TLV Specific Procedures.....................15 5.1. OVERLOAD sub-TLV Specific Procedures.......................15
6. Backward Compatibility.....................................16 6. Backward Compatibility.....................................16
7. IANA Considerations........................................16 7. IANA Considerations........................................16
7.1. OSPF TLV...................................................16 7.1. OSPF TLV...................................................16
7.2. PCED Sub-TLVs Registry.....................................16 7.2. PCED Sub-TLVs Registry.....................................16
7.3. PCE Capability Flags registry..............................17 7.3. PCE Capability Flags registry..............................17
8. Security Considerations....................................18 8. Security Considerations....................................17
9. Manageability Considerations...............................18 9. Manageability Considerations...............................18
9.1. Control of Policy and Functions............................18 9.1. Control of Policy and Functions............................18
9.2. Information and Data Model.................................18 9.2. Information and Data Model.................................18
9.3. Liveness Detection and Monitoring..........................18 9.3. Liveness Detection and Monitoring..........................18
9.4. Verify Correct Operations..................................18 9.4. Verify Correct Operations..................................18
9.5. Requirements on Other Protocols and Functional 9.5. Requirements on Other Protocols and Functional
Components...............................................19 Components...............................................18
9.6. Impact on network operations...............................19 9.6. Impact on network operations...............................19
10. Acknowledgments............................................19 10. Acknowledgments............................................19
11. References.................................................19 11. References.................................................19
11.1. Normative references.......................................19 11.1. Normative references.......................................19
11.2. Informative references.....................................20 11.2. Informative references.....................................20
12. Editors' Addresses.........................................20 12. Editor's Addresses.........................................20
13. Contributors' Addresses:...................................21 13. Contributors' Addresses....................................20
14. Intellectual Property Statement............................21 14. Intellectual Property Statement............................21
1. Terminology 1. Terminology
Terminology used in this document: Terminology used in this document:
ABR: OSPF Area Border Router. ABR: OSPF Area Border Router.
AS: Autonomous System. AS: Autonomous System.
IGP: Interior Gateway Protocol. Either of the two routing IGP: Interior Gateway Protocol. Either of the two routing
protocols Open Shortest Path First (OSPF) or Intermediate System protocols Open Shortest Path First (OSPF) or Intermediate System
to Intermediate System (ISIS). to Intermediate System (ISIS).
Intra-area TE LSP: A TE LSP whose path does not cross IGP area Intra-area TE LSP: A TE LSP whose path does not cross IGP area
boundaries. boundaries.
Intra-AS TE LSP: A TE LSP whose path does not cross AS boundaries. Intra-AS TE LSP: A TE LSP whose path does not cross AS boundaries.
Inter-area TE LSP: A TE LSP whose path transits two or more IGP Inter-area TE LSP: A TE LSP whose path transits two or more IGP
areas. That is a TE-LSP that crosses at least one IGP area boundary. areas. That is a TE-LSP that crosses at least one IGP area
boundary.
Inter-AS TE LSP: A TE LSP whose path transits two or more Inter-AS TE LSP: A TE LSP whose path transits two or more
ASes or sub-ASes (BGP confederations). That is a TE-LSP that ASes or sub-ASes (BGP confederations). That is a TE-LSP that
crosses at least one AS boundary. crosses at least one AS boundary.
LSA: Link State Advertisement LSA: Link State Advertisement
LSR: Label Switching Router. LSR: Label Switching Router.
PCC: Path Computation Client: Any client application requesting a PCC: Path Computation Client: Any client application requesting a
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distinct capabilities. In such a context it is highly desirable to distinct capabilities. In such a context it is highly desirable to
have a mechanism for automatic and dynamic PCE discovery, which have a mechanism for automatic and dynamic PCE discovery, which
allows PCCs to automatically discover a set of PCEs, along with allows PCCs to automatically discover a set of PCEs, along with
additional information about each PCE that may be required for the additional information about each PCE that may be required for the
PCC to perform PCE selection. Additionally, it is valuable for a PCC PCC to perform PCE selection. Additionally, it is valuable for a PCC
to dynamically detect new PCEs or any modification of the PCE to dynamically detect new PCEs or any modification of the PCE
information. Detailed requirements for such a PCE discovery mechanism information. Detailed requirements for such a PCE discovery mechanism
are provided in [RFC4674]. are provided in [RFC4674].
Moreover, it may also be useful to discover when a PCE experiences Moreover, it may also be useful to discover when a PCE experiences
processing congestion and when it exits such a state, in order for processing overload and when it exits such a state, in order for the
the PCCs to take some appropriate actions (e.g. to redirect their PCCs to take some appropriate actions (e.g. to redirect their
requests to another PCE). Note that the PCE selection algorithm requests to another PCE). Note that the PCE selection algorithm
applied by a PCC is out of the scope of this document. applied by a PCC is out of the scope of this document.
When PCCs are LSRs participating in the IGP (OSPF or IS-IS), and PCEs When PCCs are LSRs participating in the IGP (OSPF or IS-IS), and PCEs
are either LSRs or servers also participating in the IGP, an are either LSRs or servers also participating in the IGP, an
effective mechanism for PCE discovery within an IGP routing domain effective mechanism for PCE discovery within an IGP routing domain
consists of utilizing IGP advertisements. consists of utilizing IGP advertisements.
This document defines OSPF extensions to allow a PCE in an OSPF This document defines OSPF extensions to allow a PCE in an OSPF
routing domain to advertise its location along with some information routing domain to advertise its location along with some information
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an OSPF area or an entire OSPF routing domain. This document an OSPF area or an entire OSPF routing domain. This document
leverages this generic capability advertisement mechanism to fully leverages this generic capability advertisement mechanism to fully
satisfy the aforementioned dynamic PCE discovery requirements. satisfy the aforementioned dynamic PCE discovery requirements.
This document defines a new TLV (named the PCE Discovery (PCED) TLV) This document defines a new TLV (named the PCE Discovery (PCED) TLV)
to be carried within the OSPF Router Information LSA ([OSPF-CAP]). to be carried within the OSPF Router Information LSA ([OSPF-CAP]).
The PCE information advertised is detailed in section 3. Protocol The PCE information advertised is detailed in section 3. Protocol
extensions and procedures are defined in section 4 and 5. extensions and procedures are defined in section 4 and 5.
This document does not define any new OSPF elements of procedure. The
procedures defined in [OSPF-CAP] MUST be used.
The OSPF extensions defined in this document allow for PCE discovery The OSPF extensions defined in this document allow for PCE discovery
within an OSPF Routing domain. Solutions for PCE discovery across AS within an OSPF Routing domain. Solutions for PCE discovery across AS
boundaries are beyond the scope of this document, and for further boundaries are beyond the scope of this document, and for further
study. study.
In this document, we call TLV any TLV that is carried within an OSPF
LSA. Any TLV that is itself carried within another TLV is referred to
as either a TLV or a sub-TLV.
3. Overview 3. Overview
3.1. PCE Information 3.1. PCE Information
The PCE information advertised via OSPF falls into two categories: The PCE information advertised via OSPF falls into two categories:
PCE Discovery information and PCE Congestion information. PCE Discovery information and PCE Overload information.
3.2. PCE Discovery Information 3.2. PCE Discovery Information
The PCE Discovery information is comprised of: The PCE Discovery information is comprised of:
- The PCE location: an IPv4 and/or IPv6 address that is used to reach - The PCE location: an IPv4 and/or IPv6 address that is used to reach
the PCE. It is RECOMMENDED to use an address that is always the PCE. It is RECOMMENDED to use an address that is always
reachable; reachable;
- The PCE path computation scope (i.e. inter-area, inter-AS, inter- - The PCE path computation scope (i.e. inter-area, inter-AS, inter-
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Optional elements to describe more complex capabilities may also be Optional elements to describe more complex capabilities may also be
advertised. advertised.
PCE Discovery information is by nature fairly static and does not PCE Discovery information is by nature fairly static and does not
change with PCE activity. Changes in PCE Discovery information may change with PCE activity. Changes in PCE Discovery information may
occur as a result of PCE configuration updates, PCE occur as a result of PCE configuration updates, PCE
deployment/activation, PCE deactivation/suppression, or PCE failure. deployment/activation, PCE deactivation/suppression, or PCE failure.
Hence, this information is not expected to change frequently. Hence, this information is not expected to change frequently.
3.2.1. PCE Congestion Information 3.2.1. PCE Overload Information
The PCE Congestion information is optional information and can be The PCE Overload information is optional and can be used to report a
used to report a PCE's processing congestion state along with an PCE's overload state in order to discourage the PCCs to send new path
estimated congestion duration. This is dynamic information, which may computation requests.
change with PCE activity.
Procedures for a PCE to move from a processing congestion state to a A PCE may decide to clear the overload state according to local
non congestion state are beyond the scope of this document, but the implementation triggers (e.g. CPU utilization, average queue length
rate at which a PCE Status change is advertised MUST NOT impact by below some predefined thresholds). The rate at which a PCE Status
any means the IGP scalability. Particular attention MUST be given to change is advertised MUST NOT impact by any means the IGP
procedures to avoid state oscillations. scalability. Particular attention MUST be given on procedures to
avoid state oscillations.
3.3. Flooding Scope 3.3. Flooding Scope
The flooding scope for PCE information advertised through OSPF can be The flooding scope for PCE information advertised through OSPF can be
limited to one or more OSPF areas the PCE belongs to, or can be limited to one or more OSPF areas the PCE belongs to, or can be
extended across the entire OSPF routing domain. extended across the entire OSPF routing domain.
Note that some PCEs may belong to multiple areas, in which case the Note that some PCEs may belong to multiple areas, in which case the
flooding scope may comprise these areas. This could be the case for flooding scope may comprise these areas. This could be the case for
an ABR for instance advertising its PCE information within the an ABR for instance advertising its PCE information within the
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4. OSPF Extensions 4. OSPF Extensions
4.1. The OSPF PCED TLV 4.1. The OSPF PCED TLV
The OSPF PCE Discovery TLV (PCED TLV) is made of a set of non-ordered The OSPF PCE Discovery TLV (PCED TLV) is made of a set of non-ordered
sub-TLVs. sub-TLVs.
The format of the OSPF PCED TLV and its sub-TLVs is identical to the The format of the OSPF PCED TLV and its sub-TLVs is identical to the
TLV format used by the Traffic Engineering Extensions to OSPF TLV format used by the Traffic Engineering Extensions to OSPF
[RFC3630]. That is, the TLV is composed of 2 octets for the type, 2 [RFC3630]. That is, the TLV is comprised of 2 octets for the type, 2
octets specifying the TLV length, and a value field. The Length field octets specifying the TLV length, and a value field. The Length field
defines the length of the value portion in octets. defines the length of the value portion in octets.
The TLV is padded to four-octet alignment; padding is not included in The TLV is padded to four-octet alignment; padding is not included in
the Length field (so a three octet value would have a length of the Length field (so a three octet value would have a length of
three, but the total size of the TLV would be eight octets). Nested three, but the total size of the TLV would be eight octets). Nested
TLVs are also four-octet aligned. Unrecognized types are ignored. TLVs are also four-octet aligned. Unrecognized types are ignored.
All Type values between 32768 and 65535 are reserved for vendor- All Type values between 32768 and 65535 are reserved for vendor-
specific extensions. All other undefined Type codes are reserved for specific extensions. All other undefined Type codes are reserved for
future assignment by IANA. future assignment by IANA.
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Sub-TLVs types are under IANA control. Sub-TLVs types are under IANA control.
Currently five sub-TLVs are defined (type values to be assigned by Currently five sub-TLVs are defined (type values to be assigned by
IANA): IANA):
Sub-TLV type Length Name Sub-TLV type Length Name
1 variable PCE-ADDRESS sub-TLV 1 variable PCE-ADDRESS sub-TLV
2 4 PATH-SCOPE sub-TLV 2 4 PATH-SCOPE sub-TLV
3 variable PCE-DOMAIN sub-TLV 3 variable PCE-DOMAIN sub-TLV
4 variable NEIG-PCE-DOMAIN sub-TLV 4 variable NEIG-PCE-DOMAIN sub-TLV
5 variable PCE-CAP-FLAGS sub-TLV 5 variable PCE-CAP-FLAGS sub-TLV
6 4 CONGESTION sub-TLV 6 4 OVERLOAD sub-TLV
The PCE-ADDRESS and PATH-SCOPE sub-TLVs MUST always be present within The PCE-ADDRESS and PATH-SCOPE sub-TLVs MUST always be present within
the PCED TLV. the PCED TLV.
The PCE-DOMAIN and NEIG-PCE-DOMAIN sub-TLVs are optional. They MAY be The PCE-DOMAIN and NEIG-PCE-DOMAIN sub-TLVs are optional. They MAY be
present in the PCED TLV to facilitate selection of inter-domain PCEs. present in the PCED TLV to facilitate selection of inter-domain PCEs.
The PCE-CAP-FLAGS sub-TLV is optional and MAY be present in the PCED The PCE-CAP-FLAGS sub-TLV is optional and MAY be present in the PCED
TLV to facilitate the PCE selection process. TLV to facilitate the PCE selection process.
The CONGESTION sub-TLV is optional and MAY be present in the PCED The OVERLOAD sub-TLV is optional and MAY be present in the PCED TLV,
TLV, to indicate a PCE's processing congestion state. to indicate a PCE's processing congestion state.
Any non recognized sub-TLV MUST be silently ignored. Any non recognized sub-TLV MUST be silently ignored.
Additional sub-TLVs could be added in the future to advertise Additional sub-TLVs could be added in the future to advertise
additional information. additional information.
The PCED TLV is carried within an OSPF Router Information LSA The PCED TLV is carried within an OSPF Router Information LSA
defined in [OSPF-CAP]. defined in [OSPF-CAP].
The following sub-sections describe the sub-TLVs which may be carried The following sub-sections describe the sub-TLVs which may be carried
within the PCED sub-TLV. within the PCED sub-TLV.
4.1.1. PCE-ADDRESS Sub-TLV 4.1.1. PCE-ADDRESS Sub-TLV
The PCE-ADDRESS sub-TLV specifies the IP address(es) that can be The PCE-ADDRESS sub-TLV specifies the IP address(es) that can be
used to reach the PCE. It is RECOMMENDED to make use of an address used to reach the PCE. It is RECOMMENDED to make use of an address
that is always reachable, provided that the PCE is alive. that is always reachable, provided that the PCE is alive.
The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the
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4.1.1. PCE-ADDRESS Sub-TLV 4.1.1. PCE-ADDRESS Sub-TLV
The PCE-ADDRESS sub-TLV specifies the IP address(es) that can be The PCE-ADDRESS sub-TLV specifies the IP address(es) that can be
used to reach the PCE. It is RECOMMENDED to make use of an address used to reach the PCE. It is RECOMMENDED to make use of an address
that is always reachable, provided that the PCE is alive. that is always reachable, provided that the PCE is alive.
The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the The PCE-ADDRESS sub-TLV is mandatory; it MUST be present within the
PCED TLV. It MAY appear twice, when the PCE has both an IPv4 and IPv6 PCED TLV. It MAY appear twice, when the PCE has both an IPv4 and IPv6
address. It MUST NOT appear more than once for the same address type. address. It MUST NOT appear more than once for the same address type.
If it appears more than once, only the first occurrence MUST be
processed and other MUST be ignored.
The format of the PCE-ADDRESS sub-TLV is as follows: The format of the PCE-ADDRESS sub-TLV is as follows:
1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| address-type | Reserved | | address-type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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4.1.2. PATH-SCOPE Sub-TLV 4.1.2. PATH-SCOPE Sub-TLV
The PATH-SCOPE sub-TLV indicates the PCE path computation scope, The PATH-SCOPE sub-TLV indicates the PCE path computation scope,
which refers to the PCE's ability to compute or take part in the which refers to the PCE's ability to compute or take part in the
computation of intra-area, inter-area, inter-AS, or inter-layer_TE computation of intra-area, inter-area, inter-AS, or inter-layer_TE
LSP(s). LSP(s).
The PATH-SCOPE sub-TLV is mandatory; it MUST be present within the The PATH-SCOPE sub-TLV is mandatory; it MUST be present within the
PCED TLV. There MUST be exactly one instance of the PATH-SCOPE sub- PCED TLV. There MUST be exactly one instance of the PATH-SCOPE sub-
TLV within each PCED TLV. TLV within each PCED TLV. If it appears more than once, only the
first occurrence MUST be processed and other MUST be ignored.
The PATH-SCOPE sub-TLV contains a set of bit flags indicating the The PATH-SCOPE sub-TLV contains a set of bit flags indicating the
supported path scopes and four fields indicating PCE preferences. supported path scopes and four fields indicating PCE preferences.
The PATH-SCOPE sub-TLV has the following format: The PATH-SCOPE sub-TLV has the following format:
1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0|1|2|3|4|5| Reserved |PrefL|PrefR|PrefS|PrefY| Res | |0|1|2|3|4|5| Reserved |PrefL|PrefR|PrefS|PrefY| Res |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type To be defined by IANA (suggested value =2) Type To be defined by IANA (suggested value =2)
Length 4 Length 4
Value This comprises a 2 byte flag field where each bit Value This comprises a 2-octet flag field where each bit
represents a supported path scope, as well as four represents a supported path scope, as well as four
preference fields used to specify PCE preferences. preference fields used to specify PCE preferences.
The following bits are defined: The following bits are defined:
Bit Path Scope Bit Path Scope
0 L bit: Can compute intra-area paths 0 L bit: Can compute intra-area paths
1 R bit: Can act as PCE for inter-area TE LSP 1 R bit: Can act as PCE for inter-area TE LSP
computation computation
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Length Variable Length Variable
3 domain-type values are defined: 3 domain-type values are defined:
1 IPv4 Area Address 1 IPv4 Area Address
2 IPv6 Area Address 2 IPv6 Area Address
3 AS Number 3 AS Number
Domain ID: With the address type 1/2 this indicates the IPv4/v6 Domain ID: With the address type 1/2 this indicates the IPv4/v6
address of an area where the PCE has visibility. With address- address of an area where the PCE has visibility. With address-
type 3 this indicates an AS number where the PCE has type 3 this indicates an AS number where the PCE has
visibility. When coded in two bytes (which is the current visibility. When coded in two octets (which is the current
defined format as the time of writing this document), the AS defined format as the time of writing this document), the AS
Number field MUST have its left two bytes set to 0. Number field MUST have its first two octets set to 0.
.
4.1.4. NEIG-PCE-DOMAIN Sub-TLV 4.1.4. NEIG-PCE-DOMAIN Sub-TLV
The NEIG-PCE-DOMAIN sub-TLV specifies a neighbour PCE-domain (area, The NEIG-PCE-DOMAIN sub-TLV specifies a neighbour PCE-domain (area,
AS) toward which a PCE can compute paths. It means that the PCE can AS) toward which a PCE can compute paths. It means that the PCE can
take part in the computation of inter-domain TE LSPs whose path take part in the computation of inter-domain TE LSPs whose path
transits this neighbour PCE-domain. transits this neighbour PCE-domain.
A PCED sub-TLV MAY include several NEIG-PCE-DOMAIN sub-TLVs when the A PCED sub-TLV MAY include several NEIG-PCE-DOMAIN sub-TLVs when the
PCE can compute paths towards several neighbour PCE-domains. PCE can compute paths towards several neighbour PCE-domains.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Domain-type | Reserved | | Domain-type | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// Domain ID // // Domain ID //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
NEIG-PCE-DOMAIN sub-TLV format NEIG-PCE-DOMAIN sub-TLV format
Type To be assigned by IANA (suggested value =3) Type To be assigned by IANA (suggested value =4)
Length Variable Length Variable
3 domain-type values are defined: 3 domain-type values are defined:
1 IPv4 Area Address 1 IPv4 Area Address
2 IPv6 Area Address 2 IPv6 Area Address
3 AS Number 3 AS Number
Domain ID: With the address type 1/2 this indicates the Domain ID: With the address type 1/2 this indicates the
IPv4/v6 address of a neighbour area towards which the PCE can IPv4/v6 address of a neighbour area towards which the PCE can
compute paths. With address-type 3 this indicates the AS number compute paths. With address-type 3 this indicates the AS number
of a neighbour AS towards which the PCE can compute paths. When of a neighbour AS towards which the PCE can compute paths. When
coded in two bytes (which is the current defined format as the coded in two octets (which is the current defined format as the
time of writing this document), the AS Number field MUST have time of writing this document), the AS Number field MUST have
its left two bytes set to 0. its first two octets set to 0.
The NEIG-PCE-DOMAIN sub-TLV MUST be present if the R bit is set and The NEIG-PCE-DOMAIN sub-TLV MUST be present if the R bit is set and
the Rd bit is cleared, and/or, if the S bit is set and the Sd bit is the Rd bit is cleared, and/or, if the S bit is set and the Sd bit is
cleared. cleared.
4.1.5. PCE-CAP-FLAGS Sub-TLV 4.1.5. PCE-CAP-FLAGS Sub-TLV
The PCE-CAP-FLAGS sub-TLV is an optional sub-TLV used to indicate PCE The PCE-CAP-FLAGS sub-TLV is an optional sub-TLV used to indicate PCE
capabilities. It MAY be present within the PCED TLV. It MUST NOT be capabilities. It MAY be present within the PCED TLV. It MUST NOT be
present more than once. present more than once. If it appears more than once, only the first
occurrence MUST be processed and other MUST be ignored.
The value field of the PCE-CAP-FLAGS sub-TLV is made up of an array The value field of the PCE-CAP-FLAGS sub-TLV is made up of an array
of units of 32 flags numbered from the most significant as bit zero, of units of 32 flags numbered from the most significant as bit zero,
where each bit represents one PCE capability. where each bit represents one PCE capability.
The format of the PCE-CAP-FLAGS sub-TLV is as follows: The format of the PCE-CAP-FLAGS sub-TLV is as follows:
0 1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | | |
// PCE Capability Flags // // PCE Capability Flags //
| | | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type To be assigned by IANA (suggested value =5) Type To be assigned by IANA (suggested value =5)
Length Multiple of 4 bytes Length Multiple of 4 octets
Value This contains an array of units of 32 bit flags Value This contains an array of units of 32 bit flags
numbered from the most significant as bit zero, where numbered from the most significant as bit zero, where
each bit represents one PCE capability. each bit represents one PCE capability.
IANA is requested to manage the space of the PCE Capability Flags IANA is requested to manage the space of the PCE Capability Flags
The following bits are to be assigned by IANA: The following bits are to be assigned by IANA:
Bit Capabilities Bit Capabilities
skipping to change at page 14, line 5 skipping to change at page 14, line 5
7 Support for request prioritization 7 Support for request prioritization
8 Support for multiple requests per message 8 Support for multiple requests per message
9-31 Reserved for future assignments by IANA. 9-31 Reserved for future assignments by IANA.
These capabilities are defined in [RFC4657]. These capabilities are defined in [RFC4657].
Reserved bits SHOULD be set to zero on transmission and MUST be Reserved bits SHOULD be set to zero on transmission and MUST be
ignored on receipt. ignored on receipt.
4.1.6. The CONGESTION Sub-TLV 4.1.6. OVERLOAD Sub-TLV
The CONGESTION sub-TLV is used to indicate that a PCE is experiencing The OVERLOAD sub-TLV is used to indicate that a PCE is experiencing
a processing congestion state and may optionally include the expected a processing congestion state and may optionally include the expected
PCE congestion duration. PCE congestion duration.
The CONGESTION sub-TLV is optional, it MAY be carried within the PCED The OVERLOAD sub-TLV is optional, it MAY be carried within the PCED
TLV. It MUST NOT be present more than once. TLV. It MUST NOT be present more than once. If it appears more than
once, only the first occurrence MUST be processed and other MUST be
ignored.
The format of the CONGESTION sub-TLV is as follows: The format of the OVERLOAD sub-TLV is as follows:
0 1 2 3 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 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 | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|C| Reserved | Congestion Duration | |C| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type To be assigned by IANA (suggested value =6) Type To be assigned by IANA (suggested value =6)
Length 4 Length 4
Value Value
-C bit: When set this indicates that the PCE is experiencing -C bit: When set this indicates that the PCE is overloaded
congestion and cannot accept any new request. When and cannot accept any new request. When cleared this
cleared this indicates that the PCE is not indicates that the PCE is not overloaded and can
experiencing congestion and can accept new requests. accept new requests.
-Congestion Duration: 2-bytes, the estimated PCE congestion
duration in seconds.
When C is set and the Congestion Duration field is equal to 0, this
means that the Congestion Duration is unknown.
When C is cleared the Congestion Duration SHOULD be set to 0 and MUST
be ignored.
5. Elements of Procedure 5. Elements of Procedure
The PCED TLV is advertised within OSPFv2 Router Information LSAs The PCED TLV is advertised within OSPFv2 Router Information LSAs
(Opaque type of 4 and Opaque ID of 0) or OSPFv3 Router information (Opaque type of 4 and Opaque ID of 0) or OSPFv3 Router information
LSAs (function code of 12) which are defined in [OSPF-CAP]. As such, LSAs (function code of 12) which are defined in [OSPF-CAP]. As such,
elements of procedure are inherited from those defined in [OSPF-CAP]. elements of procedure are inherited from those defined in [OSPF-CAP].
In OSPFv2 the flooding scope is controlled by the opaque LSA type (as In OSPFv2 the flooding scope is controlled by the opaque LSA type (as
defined in [RFC2370]) and in OSPFv3 by the S1/S2 bits (as defined in defined in [RFC2370]) and in OSPFv3 by the S1/S2 bits (as defined in
skipping to change at page 15, line 11 skipping to change at page 15, line 6
bit cleared. If the flooding scope is the entire domain then the PCED bit cleared. If the flooding scope is the entire domain then the PCED
TLV MUST be carried within an OSPFv2 type 11 Router Information LSA TLV MUST be carried within an OSPFv2 type 11 Router Information LSA
or OSPFv3 Router Information LSA with the S1 bit cleared and the S2 or OSPFv3 Router Information LSA with the S1 bit cleared and the S2
bit set. When only the L bit of the PATH-SCOPE sub-TLV is set, the bit set. When only the L bit of the PATH-SCOPE sub-TLV is set, the
flooding scope MUST be area local. flooding scope MUST be area local.
An OSPF router MUST originate a new Router Information LSA whenever An OSPF router MUST originate a new Router Information LSA whenever
there is a change in a PCED TLV associated with a PCE it advertises. there is a change in a PCED TLV associated with a PCE it advertises.
When a PCE is deactivated, the OSPF router advertising this PCE MUST When a PCE is deactivated, the OSPF router advertising this PCE MUST
originate a new Router Information LSA that does no longer include originate a new Router Information LSA that no longer includes the
the corresponding PCED TLV. corresponding PCED TLV.
The PCE address, i.e. the address indicated within the PCE ADDRESS The PCE address, i.e. the address indicated within the PCE ADDRESS
TLV, MUST be reachable via some prefixes advertised by OSPF; this TLV, SHOULD be reachable via some prefixes advertised by OSPF; this
allows speeding up the detection of a PCE failure. Note that when the allows speeding up the detection of a PCE failure. Note that when the
PCE address is no longer reachable, this means that the PCE node has PCE address is no longer reachable, this means that the PCE node has
failed or has been torn down, or that there is no longer IP failed or has been torn down, or that there is no longer IP
connectivity to the PCE node. connectivity to the PCE node.
The PCED TLV is OPTIONAL. When an OSPF LSA does not contain any PCED
TLV, this means that the PCE information of that node is unknown.
A change in PCED information MUST NOT trigger any SPF computation at A change in PCED information MUST NOT trigger any SPF computation at
a receiving router. a receiving router.
The way PCEs determine the information they advertise is out of the The way PCEs determine the information they advertise is out of the
scope of this document. Some information may be configured on the PCE scope of this document. Some information may be configured on the PCE
(e.g., address, preferences, scope) and other information may be (e.g., address, preferences, scope) and other information may be
automatically determined by the PCE (e.g., areas of visibility). automatically determined by the PCE (e.g., areas of visibility).
5.1. CONGESTION sub-TLV Specific Procedures 5.1. OVERLOAD sub-TLV Specific Procedures
When a PCE enters into a processing congestion state, the conditions
of which are implementation dependent, a Router Information LSA with
a CONGESTION sub-TLV with the C bit set, and optionally a non-null
expected congestion duration MAY be generated.
When a PCE exits from the processing congestion state, the conditions When a PCE enters into an overload state, the conditions of which are
of which are implementation dependent, two cases are considered: implementation dependent, a Router Information LSA with an OVERLOAD
- If the congestion duration in the previously originated sub-TLV with the C bit set MAY be generated.
CONGESITON sub-TLV was null, a CONGESTION sub-TLV with the C bit
cleared SHOULD be generated;
- If the congestion duration in the previously originated
CONGESTION sub-TLV was non null, a CONGESTION sub-TLV with the C bit
cleared MAY be generated. Note that in some particular cases it may
be desired to originate a CONGESTION sub-TLV with the C bit cleared
if the congestion duration was over estimated.
The congestion duration allows a reduction in the amount of OSPF When a PCE exits from an overload state, the conditions of which
flooding, as only uncongested-to-congested state transitions need to are implementation dependent (e.g. CPU utilization, average queue
be advertised. length below some pre-defined threshold), a new Router Information
LSA with an OVERLOAD sub-TLV with the C bit cleared SHOULD be
generated, if the overload information had been previously
advertised.
An OSPF implementation SHOULD support an appropriate dampening A PCE implementation supporting the OSPF extensions defined in this
algorithm so as to dampen OSPF flooding of PCE Congestion information document SHOULD support an appropriate dampening algorithm so as to
in order to not impact the OSPF scalability. It is RECOMMENDED to dampen OSPF flooding of PCE Overload information in order to not
introduce some hysteresis for congestion state transition, so as to impact the OSPF scalability. It is RECOMMENDED to introduce some
avoid state oscillations that may impact OSPF performance. For hysteresis for overload state transition, so as to avoid state
instance two thresholds MAY be configured: A resource congestion oscillations that may impact OSPF performance. For instance two
upper-threshold and a resource congestion lower-threshold. An LSR thresholds MAY be configured: An upper-threshold and a lower-
enters the congested state when the CPU load reaches the upper threshold; an LSR enters the overload state when the CPU load reaches
threshold and leaves the congested state when the CPU load goes under the upper threshold and leaves the overload state when the CPU load
the lower threshold. goes under the lower threshold.
Upon receipt of an updated CONGESTION sub-TLV a PCC SHOULD take Upon receipt of an updated OVERLOAD sub-TLV a PCC SHOULD take
appropriate actions. In particular, the PCC SHOULD stop sending appropriate actions. In particular, the PCC SHOULD stop sending
requests to a congested PCE, and SHOULD gradually start sending requests to an overloaded PCE, and SHOULD gradually start sending
again requests to a PCE that is no longer congested. again requests to a PCE that is no longer overloaded.
6. Backward Compatibility 6. Backward Compatibility
The PCED TLV defined in this document does not introduce any The PCED TLV defined in this document does not introduce any
interoperability issues. interoperability issues.
A router not supporting the PCED TLV will just silently ignore the A router not supporting the PCED TLV will just silently ignore the
TLV as specified in [OSPF-CAP]. TLV as specified in [OSPF-CAP].
7. IANA Considerations 7. IANA Considerations
skipping to change at page 17, line 6 skipping to change at page 16, line 41
registry defined in [OSPF-CAP], named the "OSPF PCED sub-TLV" registry defined in [OSPF-CAP], named the "OSPF PCED sub-TLV"
registry, and manage sub-TLV type identifiers as follows: registry, and manage sub-TLV type identifiers as follows:
- sub-TLV Type - sub-TLV Type
- sub-TLV Name - sub-TLV Name
- Reference - Reference
This document defines five sub-TLVs as follows (suggested values): This document defines five sub-TLVs as follows (suggested values):
Sub-TLV Sub-TLV Sub-TLV Sub-TLV
Type Name References Type Name Reference
----- -------- ---------- ----- -------- ----------
1 PCE-ADDRESS This document 1 PCE-ADDRESS This document
2 PATH-SCOPE This document 2 PATH-SCOPE This document
3 PCE-DOMAIN This document 3 PCE-DOMAIN This document
4 NEIG-PCE-DOMAIN This document 4 NEIG-PCE-DOMAIN This document
5 PCE-CAP-FLAGS This document 5 PCE-CAP-FLAGS This document
6 CONGESTION This document 6 OVERLOAD This document
New sub-TLV type values may be allocated only by an IETF Consensus New sub-TLV type values may be allocated only by an IETF Consensus
action. action.
7.3. PCE Capability Flags Registry 7.3. PCE Capability Flags Registry
This document provides new capability bit flags, which are present This document provides new capability bit flags, which are present
in the PCE-CAP-FLAGS TLV referenced in section 4.1.5. in the PCE-CAP-FLAGS TLV referenced in section 4.1.5.
The IANA is requested to create a new top-level OSPF registry, the The IANA is requested to create a new top-level OSPF registry, the
skipping to change at page 18, line 15 skipping to change at page 17, line 50
8. Security Considerations 8. Security Considerations
This document defines OSPF extensions for PCE discovery within an This document defines OSPF extensions for PCE discovery within an
administrative domain. Hence the security of the PCE discovery relies administrative domain. Hence the security of the PCE discovery relies
on the security of OSPF. on the security of OSPF.
Mechanisms defined to ensure authenticity and integrity of OSPF LSAs Mechanisms defined to ensure authenticity and integrity of OSPF LSAs
[RFC2154], and their TLVs, can be used to secure the PCE Discovery [RFC2154], and their TLVs, can be used to secure the PCE Discovery
information as well. information as well.
OSPF provides no mechanism for protecting the privacy of LSAs, and in OSPF provides no encryption mechanism for protecting the privacy of
particular the privacy of the PCE discovery information. LSAs, and in particular the privacy of the PCE discovery information.
9. Manageability Considerations 9. Manageability Considerations
Manageability considerations for PCE Discovery are addressed in Manageability considerations for PCE Discovery are addressed in
section 4.10 of [RFC4674]. section 4.10 of [RFC4674].
9.1. Control of Policy and Functions 9.1. Control of Policy and Functions
Requirements on the configuration of PCE discovery parameters on PCCs Requirements on the configuration of PCE discovery parameters on PCCs
and PCEs are discussed in section 4.10.1 of [RFC4674]. and PCEs are discussed in section 4.10.1 of [RFC4674].
skipping to change at page 19, line 11 skipping to change at page 18, line 49
9.4. Verify Correct Operations 9.4. Verify Correct Operations
The correlation of information advertised against information The correlation of information advertised against information
received can be achieved by comparing the PCED information in the PCC received can be achieved by comparing the PCED information in the PCC
and in the PCE, which is stored in the PCED MIB [PCED-MIB]. The and in the PCE, which is stored in the PCED MIB [PCED-MIB]. The
number of dropped, corrupt, and rejected information elements are number of dropped, corrupt, and rejected information elements are
stored in the PCED MIB. stored in the PCED MIB.
9.5. Requirements on Other Protocols and Functional Components 9.5. Requirements on Other Protocols and Functional Components
The OSPF extensions defined in this documents do not imply any The OSPF extensions defined in this document do not imply any
requirement on other protocols. requirement on other protocols.
9.6. Impact on network operations 9.6. Impact on network operations
Frequent changes in PCE information, and particularly in PCE Frequent changes in PCE information, and particularly in PCE overload
congestion information, may have a significant impact on OSPF and information, may have a significant impact on OSPF and might
might destabilize the operation of the network by causing the PCCs to destabilize the operation of the network by causing the PCCs to swap
swap between PCEs. between PCEs.
As discussed in section 5.1, a PCE implementation SHOULD support an As discussed in section 5.1, a PCE implementation SHOULD support an
appropriate dampening algorithm so as to dampen OSPF flooding in appropriate dampening algorithm so as to dampen OSPF flooding in
order to not impact the OSPF scalability. order to not impact the OSPF scalability.
Also, as discussed in section 4.10.4 of [RFC4674], it MUST be Also, as discussed in section 4.10.4 of [RFC4674], it MUST be
possible to apply at least the following controls: possible to apply at least the following controls:
- Configurable limit on the rate of announcement of changed - Configurable limit on the rate of announcement of changed
parameters at a PCE. parameters at a PCE.
- Control of the impact on PCCs such as through discovery messages - Control of the impact on PCCs such as through discovery messages
rate-limiting. rate-limiting.
- Configurable control of triggers that cause a PCC to swap to - Configurable control of triggers that cause a PCC to swap to
another PCE. another PCE.
10. Acknowledgments 10. Acknowledgments
We would like to thank Lucy Wong, Adrian Farrel, Les Ginsberg, Mike We would like to thank Lucy Wong, Adrian Farrel, Les Ginsberg, Mike
Shand and Lou Berger for their useful comments and suggestions. Shand and Lou Berger for their useful comments and suggestions.
We would also like to thank Dave Ward, Lars Eggert, Sam Hartman, and
Tim Polk for their comments during the final stages of publication.
11. References 11. References
11.1. Normative references 11.1. Normative references
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2740] Coltun, R., Ferguson, D., and J. Moy, "OSPF for IPv6", [RFC2740] Coltun, R., Ferguson, D., and J. Moy, "OSPF for IPv6",
RFC 2740, December 1999. RFC 2740, December 1999.
[RFC2370] Coltun, R., "The OSPF Opaque LSA Option", RFC 2370, July [RFC2370] Coltun, R., "The OSPF Opaque LSA Option", RFC 2370, July
1998. 1998.
[RFC3630] Katz, D., Yeung, D., Kompella, K., "Traffic Engineering [RFC3630] Katz, D., Yeung, D., Kompella, K., "Traffic Engineering
Extensions to OSPF Version 2", RFC 3630, September 2003. Extensions to OSPF Version 2", RFC 3630, September 2003.
[OSPF-CAP] Lindem, A., Shen, N., Aggarwal, R., Shaffer, S., Vasseur, [OSPF-CAP] Lindem, A., Shen, N., Aggarwal, R., Shaffer, S., Vasseur,
J.P., "Extensions to OSPF for advertising Optional Router J.P., "Extensions to OSPF for advertising Optional Router
Capabilities", draft-ietf-ospf-cap, work in progress. Capabilities", draft-ietf-ospf-cap, work in progress.
11.2. Informative references
[RFC2154] Murphy, S., Badger, M., and B. Wellington, "OSPF with [RFC2154] Murphy, S., Badger, M., and B. Wellington, "OSPF with
Digital Signatures", RFC 2154, June 1997. Digital Signatures", RFC 2154, June 1997.
[RFC4655] Farrel, A., Vasseur, J.P., Ash, J., "Path Computation 11.2. Informative references
Element (PCE)-based Architecture", RFC4655, August 2006.
[RFC4657] Ash, J., Le Roux, J.L., "PCE Communication Protocol Generic [RFC4657] Ash, J., Le Roux, J.L., "PCE Communication Protocol Generic
Requirements", RFC4657, September 2006. Requirements", RFC4657, September 2006.
[RFC4674] Le Roux, J.L., et al. "Requirements for PCE discovery",
RFC4674, October 2006.
[PCEP] Vasseur, Le Roux, et al., "Path Computation Element (PCE) [PCEP] Vasseur, Le Roux, et al., "Path Computation Element (PCE)
communication Protocol (PCEP) - Version 1", draft-ietf-pce- communication Protocol (PCEP) - Version 1", draft-ietf-pce-pcep, work
pcep, work in progress. in progress.
[PCED-MIB] Stephan, E., "Definitions of Managed Objects for Path [PCED-MIB] Stephan, E., "Definitions of Managed Objects for Path
Computation Element Discovery", draft-ietf-pce-disc-mib, Computation Element Discovery", draft-ietf-pce-disc-mib, work in
work in progress. progress.
12. Editors' Addresses [PCED-ISIS] Le Roux, Vasseur, et al. "IS-IS protocol extensions for
Path Computation Element (PCE) Discovery", draft-ietf-pce-disco-
proto-isis, work in progress.
[RFC4655] Farrel, A., Vasseur, J.P., Ash, J., "Path Computation
Element (PCE)-based Architecture", RFC4655, August 2006.
[RFC4674] Le Roux, J.L., et al. "Requirements for PCE discovery",
RFC4674, October 2006.
12. Editor's Addresses
Jean-Louis Le Roux (Editor) Jean-Louis Le Roux (Editor)
France Telecom France Telecom
2, avenue Pierre-Marzin 2, avenue Pierre-Marzin
22307 Lannion Cedex 22307 Lannion Cedex
FRANCE FRANCE
Email: jeanlouis.leroux@orange-ftgroup.com Email: jeanlouis.leroux@orange-ftgroup.com
Jean-Philippe Vasseur (Editor) Jean-Philippe Vasseur (Editor)
Cisco Systems, Inc. Cisco Systems, Inc.
1414 Massachusetts avenue 1414 Massachusetts avenue
Boxborough , MA - 01719 Boxborough , MA - 01719
USA USA
Email: jpv@cisco.com Email: jpv@cisco.com
13. Contributors' Addresses: 13. Contributors' Addresses
Yuichi Ikejiri Yuichi Ikejiri
NTT Communications Corporation NTT Communications Corporation
1-1-6, Uchisaiwai-cho, Chiyoda-ku 1-1-6, Uchisaiwai-cho, Chiyoda-ku
Tokyo 100-8019 Tokyo 100-8019
JAPAN JAPAN
Email: y.ikejiri@ntt.com Email: y.ikejiri@ntt.com
Raymond Zhang Raymond Zhang
BT Infonet BT Infonet
2160 E. Grand Ave. 2160 E. Grand Ave.
El Segundo, CA 90025 El Segundo, CA 90025
USA USA
Email: raymond_zhang@bt.infonet.com Email: raymond_zhang@bt.infonet.com
14. Intellectual Property Statement 14. Intellectual Property Statement
The IETF takes no position regarding the validity or scope of any The IETF takes no position regarding the validity or scope of any
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