Networking Working Group JP. Vasseur, Ed.
Internet-Draft Cisco Systems, Inc
Intended status: Standards Track JL. Leroux, Ed.
Expires: July 27, 2007 France Telecom
S. Yasukawa
NTT
S. Previdi
P. Psenak
Cisco Systems, Inc
P. Mabbey
Comcast
January 23, 2007
Routing extensions for discovery of Multiprotocol (MPLS) Label Switch
Router (LSR) Traffic Engineering (TE) mesh membership
draft-ietf-ccamp-automesh-04.txt
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Copyright (C) The IETF Trust (2007).
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Abstract
The set up of a full mesh of Multi-Protocol Label Switching (MPLS)
Traffic Engineering (TE) Label Switched Paths (LSP) among a set of
Label Switch Routers (LSR) is a common deployment scenario of MPLS
Traffic Engineering either for bandwidth optimization, bandwidth
guarantees or fast rerouting with MPLS Fast Reroute. Such deployment
may require the configuration of potentially a large number of TE
LSPs (on the order of the square of the number LSRs). This document
specifies Interior Gateway Protocol (IGP) routing extensions for
Intermediate System-to-Intermediate System (IS-IS) and Open Shortest
Path First (OSPF) so as to provide an automatic discovery of the set
of LSRs members of a mesh in order to automate the creation of such
mesh of TE LSPs.
Requirements Language
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].
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Table of Contents
1. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Description of a TE Mesh-Group . . . . . . . . . . . . . . . . 5
4. TE-MESH-GROUP TLV formats . . . . . . . . . . . . . . . . . . 6
4.1. OSPF TE-MESH-GROUP TLV format . . . . . . . . . . . . . . 6
4.2. IS-IS TE-MESH-GROUP sub-TLV format . . . . . . . . . . . . 8
5. Elements of procedure . . . . . . . . . . . . . . . . . . . . 9
5.1. OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.2. IS-IS . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6. Backward compatibility . . . . . . . . . . . . . . . . . . . . 12
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
7.1. OSPF . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
7.2. IS-IS . . . . . . . . . . . . . . . . . . . . . . . . . . 12
8. Security Considerations . . . . . . . . . . . . . . . . . . . 13
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . . 13
10.2. Informative References . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
Intellectual Property and Copyright Statements . . . . . . . . . . 16
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1. Terminology
Terminology used in this document
IGP: Interior Gateway Protocol.
IGP Area: OSPF area or IS-IS level.
IS-IS: Intermediate System-to-Intermediate System (IS-IS).
LSR: Label Switch Router.
OSPF: Open Shortest Path First (OSPF).
OSPF LSA: OSPF Link State Advertisement.
TE LSP: Traffic Engineering Label Switched Path.
TE LSP head-end: head/source of the TE LSP.
TE LSP tail-end: tail/destination of the TE LSP.
TLV: Type Lenght Value
2. Introduction
There are two well-known approaches in deploying MPLS Traffic
Engineering:
(1) The so-called "strategic" approach that consists of setting up a
full mesh of TE LSPs between a set of LSRs,
(2) The so-called "tactical" approach where a set of TE LSPs are
provisioned on well identified "hot spots" in order to alleviate a
congestion resulting for instance from an unexpected traffic growth
in some parts of the network.
The set up of a full mesh of TE LSPs among a set of LSRs is a common
deployment scenario of MPLS Traffic Engineering either for bandwidth
optimization, bandwidth guarantees or fast rerouting with MPLS Fast
Reroute. Setting up a full mesh of TE LSPs between N LSRs requires
the configuration of a potentially large number of TE LSPs (O(N^2)).
Furthermore, the addition of any new LSR in the mesh requires the
configuration of N additional TE LSPs on the new LSR and one new TE
LSP on every LSR of the existing mesh destined to this new LSR, which
gives a total of 2*N TE LSPs to be configured. Such operation is not
only time consuming but also a risky operation (prone to
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misconfiguration) for Service Providers. Hence, an automatic
mechanism for setting up TE LSPs meshes is desirable and requires the
ability to automatically discover the set of LSRs that belong to the
mesh. This document specifies routing extensions so as to
automatically discover the members of a mesh, also referred to as a
"TE mesh-group". Note that the mechanism(s) needed for the dynamic
creation of TE LSPs is implementation specific and outside the scope
of this document.
Routing extensions have been defined in [I-D.ietf-ospf-cap] and
[I-D.ietf-isis-caps] in order to advertise router capabilities. This
document specifies IGP (OSPF and IS-IS) TE Mesh Group (Type Lenght
Value) TLVs allowing for the automatic discovery of a TE mesh-group
members, to be carried in the OSPF Router Information (Link State
Advertisement) LSA [I-D.ietf-ospf-cap] and IS-IS Router Capability
TLV [I-D.ietf-isis-caps]. The routing extensions specified in this
document provide the ability to signal multiple TE mesh groups. An
LSR may belong to more than one TE mesh-group(s).
There are relatively tight real-time constraints on the operation of
IGPs (such as OSPF and IS-IS). For this reason some care needs to be
applied when proposing to carry additional information in an IGP.
The information described in this document is both relatively small
in total volume (compared with other information already carried in
IGPs), and also relatively stable (ie, changes are based on
configuration changes, but not based on dynamic events within the
network, and not based on dynamic triggers such as the leaking of
information from other routing protocols or routing protocol
instances).
3. Description of a TE Mesh-Group
A TE mesh-group is defined as a group of LSRs that are connected by a
full mesh of TE LSPs. Routing extensions are specified in this
document allowing for dynamic discovery of the TE mesh-group members.
Procedures are also specified for a member to join and leave a TE
mesh-group. For each TE mesh-group membership announced by an LSR,
the following information is avdertized:
- A mesh-group number identifying the TE mesh-group the LSR belongs
to,
- A Tail-end address (used as the TE LSP Tail-end address by other
LSRs belonging to the same mesh-group),
- A Tail-end name: a display string that is allocated to the Tail-end
used to ease the TE-LSP naming.
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4. TE-MESH-GROUP TLV formats
4.1. OSPF TE-MESH-GROUP TLV format
The TE-MESH-GROUP TLV is used to advertise the desire of an LSR to
join/leave a given TE mesh-group. No sub-TLV is currently defined
for the TE-MESH-GROUP TLV.
The OSPF TE-MESH-GROUP TLV (advertised in an OSPF router information
LSA defined in [I-D.ietf-ospf-cap]) has the following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
// Value //
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1 - OSPF TE-MESH-GROUP TLV format
Where
Type: identifies the TLV type
Length: length of the value field in octets
The format of the OSPF TE-MESH-GROUP TLV is the same as the TLV
format used by the Traffic Engineering Extensions to OSPF
(see[RFC3630]). 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 three, but the total size of the TLV would be eight
octets). Nested TLVs are also 32-bit aligned. Unrecognized types
are ignored. All types between 32768 and 65535 are reserved for
vendor-specific extensions. All other undefined type codes are
reserved for future assignment by IANA.
The OSPF TE-MESH-GROUP TLV format for IPv4 (figure 2) and IPv6
(figure 3) is as follows:
TYPE: To be assigned by IANA (Suggested Value: 3)
LENGTH: Variable
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tail-end IPv4 address 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name 1 |
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tail-end IPv4 address n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2 - OSPF TE-MESH-GROUP TLV format (IPv4 Address)
TYPE: To be assigned by IANA (Suggested Value: 4)
LENGTH: Variable
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Tail-end IPv6 address 1 |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Tail-end IPv6 address n |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3 - OSPF TE-MESH-GROUP TLV format (IPv6 Address)
The OSPF TE-MESH-GROUP TLV may contain one or more mesh-group entries
where each entry correspond to a TE mesh-group and is made of the
following fields:
- A mesh-group-number that identifies the mesh-group number,
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- A Tail-end address: an IPv4 or IPv6 IP address to be used as a
tail-end TE LSP address by other LSRs belonging to the same mesh-
group,
- A Tail-end name: A display string that is allocated to the Tail-
end. The field is of variable length field and is used to facilitate
the TE LSP identification. - Name length field: An integer, expressed
in octets, that indicates the length of the Tail-end name before
padding.
4.2. IS-IS TE-MESH-GROUP sub-TLV format
The TE-MESH-GROUP sub-TLV is used to advertise the desire of an LSR
to join/leave a given TE mesh-group. No sub-TLV is currently defined
for the TE-MESH-GROUP sub-TLV.
The IS-IS TE-MESH-GROUP sub-TLV (advertised in the IS-IS CAPABILITY
TLV defined in [I-D.ietf-isis-caps] ) is composed of 1 octet for the
type, 1 octet specifying the TLV length and a value field. The
format of the TE-MESH-GROUP sub-TLV is identical to the TLV format
used by the Traffic Engineering Extensions for IS-IS [RFC3784].
The IS-IS TE-MESH-GROUP sub-TLV format for IPv4 (figure 4) and IPv6
(figure 5) is as follows:
TYPE: To be assigned by IANA (Suggested value: 3).
LENGTH: Variable
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tail-end IPv4 address 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tail-end IPv4 address n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4 - IS-IS TE-MESH-GROUP sub-TLV format (IPv4 Address)
TYPE: To be assigned by IANA (Suggested Value: 4)
LENGTH: Variable
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Tail-end IPv6 address 1 |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mesh-group-number n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| Tail-end IPv6 address n |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name length | Tail-end name n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5 - IS-IS TE-MESH-GROUP sub-TLV format (IPv6 Address)
The IS-IS TE-MESH-GROUP sub-TLV may contain one or more mesh-group
entries where each entry correspond to a TE mesh-group and is made of
the following fields:
- A mesh-group-number that identifies the mesh-group number,
- A Tail-end address: an IPv4 or IPv6 IP address to be used as a
tail-end TE LSP address by other LSRs belonging to the same mesh-
group,
- A Tail-end name: A display string that is allocated to the Tail-
end. The field is of variable length field and is used to facilitate
the TE LSP identification. - Name length field: An integer, expressed
in octets, that indicates the length of the Tail-end name before
padding.
5. Elements of procedure
The OSPF TE-MESH-GROUP TLV is carried within the OSPF Routing
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Information LSA and the TE-MESH-GROUP sub-TLV is caried within the
IS-IS Router capability TLV. As such, elements of procedure are
inherited from those defined in [I-D.ietf-ospf-cap] and
[I-D.ietf-isis-caps] for OSPF and IS-IS respectively. Specifically,
a router MUST originate a new LSA/LSP whenever the content of this
information changes, or whenever required by regular routing
procedure (e.g. update).
The TE-MESH-GROUP TLV is OPTIONAL and MUST NOT include more than one
of each of the IPv4 instance or the IPv6 instance. If either the
IPv4 or the IPv6 OSPF TE-MESH-GROUP TLV occurs more than once within
the OSPF Router Information LSA, only the first instance is
processed, subsequent TLV(s) SHOULD be silently ignored. Similarly,
if either the IPv4 or the IPv6 IS-IS TE-MESH-GROUP sub-TLV occurs
more than once within the ISIS Router capability TLV, only the first
instance is processed, subsequent TLV(s) SHOULD be silently ignored.
5.1. OSPF
The TE-MESH-GROUP TLV is advertised within an OSPF Router Information
opaque LSA (opaque type of 4, opaque ID of 0) for OSPFv2 ([RFC2328])
and within a new LSA (Router Information LSA) for OSPFv3 ([RFC2740]).
The Router Information LSAs for OSPFv2 and OSPFv3 are defined in
([I-D.ietf-ospf-cap]).
A router MUST originate a new OSPF router information LSA whenever
the content of the any of the advertised TLV changes or whenever
required by the regular OSPF procedure (LSA update (every
LSRefreshTime)). If an LSR desires to join or leave a particular TE
mesh group, it MUST originate a new OSPF Router Information LSA
comprising the updated TE-MESH-GROUP TLV. In the case of a join, a
new entry will be added to the TE-MESH-GROUP TLV; conversely, if the
LSR leaves a mesh-group the corresponding entry will be removed from
the TE-MESH-GROUP TLV. Note that both operations can be performed in
the context of a single LSA update. An implementation SHOULD be able
to detect any change to a previously received TE-MESH-GROUP TLV from
a specific LSR.
As defined in [RFC2370] for OSPVv2 and in [RFC2740] for OSPFv3, the
flooding scope of the Router Information LSA is determined by the LSA
Opaque type for OSPFv2 and the values of the S1/S2 bits for OSPFv3.
For OSPFv2 Router Information opaque LSA:
- Link-local scope: type 9;
- Area-local scope: type 10;
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- Routing-domain scope: type 11. In this case, the flooding scope is
equivalent to the Type 5 LSA flooding scope.
For OSPFv3 Router Information LSA:
- Link-local scope: OSPFV3 Router Information LSA with the S1 and S2
bits cleared;
- Area-local scope: OSPFV3 Router Information LSA with the S1 bit set
and the S2 bit cleared;
- Routing-domain scope: OSPFv3 Router Information LSA with S1 bit
cleared and the S2 bit set.
A router may generate multiple OSPF Router Information LSAs with
different flooding scopes.
The TE-MESH-GROUP TLV may be advertised within an Area-local or
Routing-domain scope Router Information LSA depending on the MPLS TE
mesh group profile:
- If the MPLS TE mesh-group is contained within a single area (all
the LSRs of the mesh-group are contained within a single area), the
TE-MESH-GROUP TLV MUST be generated within an Area-local Router
Information LSA.
- If the MPLS TE mesh-group spans multiple OSPF areas, the TE mesh-
group TLV MUST be generated within a Routing-domain scope router
information LSA.
5.2. IS-IS
The TE-MESH-GROUP sub-TLV is advertised within the IS-IS Router
CAPABILITY TLV defined in [I-D.ietf-isis-caps]. An IS-IS router MUST
originate a new IS-IS LSP whenever the content of the any of the
advertised sub-TLV changes or whenever required by regular IS-IS
procedure (LSP update). If an LSR desires to join or leave a
particular TE mesh group, it MUST originate a new LSP comprising the
refreshed IS-IS Router capability TLV comprising the updated TE-MESH-
GROUP sub-TLV. In the case of a join, a new entry will be added to
the TE-MESH-GROUP sub-TLV; conversely, if the LSR leaves a mesh-group
the corresponding entry will be deleted from the TE-MESH-GROUP sub-
TLV. Note that both operations can be performed in the context of a
single update. An implementation SHOULD be able to detect any change
to a previously received TE-MESH-GROUP sub-TLV from a specific LSR.
If the flooding scope of an MPLS Traffic Engineering capability is
limited to an IS-IS level/area, the sub-TLV MUST not be leaked across
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level/area and the S flag of the Router CAPABILITY TLV MUST be
cleared. Conversely, if the flooding scope of an MPLS Traffic
Engineering capability is the entire routing domain, the TLV MUST be
leaked across IS-IS levels/areas, and the S flag of the Router
CAPABILITY TLV MUST be set. In both cases the flooding rules
specified in [I-D.ietf-isis-caps] apply.
As specified in [I-D.ietf-isis-caps], a router may generate multiple
IS-IS Router CAPABILITY TLVs within an IS-IS LSP with different
flooding scopes.
6. Backward compatibility
The TE-MESH-GROUP TLVs defined in this document do not introduce any
interoperability issue. For OSPF, a router not supporting the TE-
MESH-GROUP TLV SHOULD just silently ignore the TLV as specified in
[RFC2370]. For IS-IS a router not supporting the TE-MESH-GROUP sub-
TLV SHOULD just silently ignore the sub-TLV.
7. IANA Considerations
7.1. OSPF
Once a registry for the Router Information LSA defined in
[I-D.ietf-ospf-cap] will have been assigned, IANA will assign a new
OSPF TLV code-point for the TE-MESH-GROUP TLVs carried within the
Router Information LSA.
Value Sub-TLV References
----- -------- ----------
3 TE-MESH-GROUP TLV (IPv4) draft-ietf-ospf-cap (to be replaced by RFC number)
4 TE-MESH-GROUP TLV (IPv6) draft-ietf-ospf-cap (to be replaced by RFC number)
7.2. IS-IS
Once a registry for the Router Capability TLV defined in
[I-D.ietf-isis-caps] will have been assigned, IANA will assign a new
IS-IS sub-TLV code-point for the TE-MESH-GROUP sub-TLVs carried
within the IS-IS Router Capability TLV.
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Value Sub-TLV References
----- -------- ----------
3 TE-MESH-GROUP TLV (IPv4) draft-ietf-isis-caps (to be replaced by RFC number)
4 TE-MESH-GROUP TLV (IPv6) draft-ietf-isis-caps (to be replaced by RFC number)
8. Security Considerations
The function described in this document does not create any new
security issues for the OSPF and the IS-IS protocols. Security
considerations are covered in [RFC2328] and [RFC2740] for the base
OSPF protocol and in [RFC1195] for IS-IS. It must be noted that the
advertisement of "fake" TE Mesh Group membership(s) by a mis-
configured or malicious LSR Y would not have any major impact on the
network (other than overloading the IGP) such as triggering the set
up of new MPLS TE LSP: indeed for a new TE LSP originated by another
LSR X destined to LSR Y to be set up, the same TE Mesh group
membership must be configured on both LSRs. Thus such fake
advertisement could not amplify any DoS attack.
9. Acknowledgements
We would like to thank Dean Cheng, Adrian Farrel, Yannick Le Louedec,
Dave Ward, Les Ginsberg, Stephen Nadas, Acee Lindem, Dimitri
Papadimitriou and Lakshminath Dondeti for their useful comments.
10. References
10.1. Normative References
[I-D.ietf-isis-caps]
Vasseur, J., "IS-IS Extensions for Advertising Router
Information", draft-ietf-isis-caps-06 (work in progress),
January 2006.
[I-D.ietf-ospf-cap]
Lindem, A., "Extensions to OSPF for Advertising Optional
Router Capabilities", draft-ietf-ospf-cap-09 (work in
progress), October 2006.
[RFC1194] Zimmerman, D., "Finger User Information Protocol",
RFC 1194, November 1990.
[RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
dual environments", RFC 1195, December 1990.
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.
[RFC2370] Coltun, R., "The OSPF Opaque LSA Option", RFC 2370,
July 1998.
[RFC2740] Coltun, R., Ferguson, D., and J. Moy, "OSPF for IPv6",
RFC 2740, December 1999.
10.2. Informative References
[RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
(TE) Extensions to OSPF Version 2", RFC 3630,
September 2003.
[RFC3784] Smit, H. and T. Li, "Intermediate System to Intermediate
System (IS-IS) Extensions for Traffic Engineering (TE)",
RFC 3784, June 2004.
Authors' Addresses
JP Vasseur (editor)
Cisco Systems, Inc
1414 Massachusetts Avenue
Boxborough, MA 01719
USA
Email: jpv@cisco.com
JL Le Roux (editor)
France Telecom
2, Avenue Pierre-Marzin
Lanion, 22307
FRANCE
Email: jeanlouis.leroux@francetelecom.com
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Seisho Yasukawa
NTT
9-11, Midori-Cho 3-Chome
Tokyo, 180-8585
JAPAN
Email: yasukawa.seisho@lab.ntt.co.jp
Stefano Previdi
Cisco Systems, Inc
Via Del Serafico 200
Roma, 00142
Italy
Email: sprevidi@cisco.com
Peter Psenak
Cisco Systems, Inc
Pegasus Park DE Kleetlaan 6A
Diegmen, 1831
BELGIUM
Email: ppsenak@cisco.com
Paul Mabbey
Comcast
USA
Email:
Vasseur, et al. Expires July 27, 2007 [Page 15]
Internet-Draft draft-ietf-ccamp-automesh-04.txt January 2007
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Vasseur, et al. Expires July 27, 2007 [Page 16]
