Network Working Group R. Aggarwal
Internet Draft Juniper Networks
Category: Standards Track
Expiration Date: August 2011
J. L. Le Roux
France Telecom
February 02, 2011
MPLS Upstream Label Assignment for LDP
draft-ietf-mpls-ldp-upstream-10.txt
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Abstract
This document describes procedures for distributing upstream-assigned
labels for Label Distribution Protocol (LDP). It also describes how
these procedures can be used for avoiding branch Label Switching
Router (LSR) traffic replication on a LAN for LDP point-to-multipoint
(P2MP) Label Switched Paths (LSPs).
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Table of Contents
1 Specification of requirements ......................... 3
2 Introduction .......................................... 3
3 LDP Upstream Label Assignment Capability .............. 4
4 Distributing Upstream-Assigned Labels in LDP .......... 5
4.1 Procedures ............................................ 5
5 LDP Tunnel Identifier Exchange ........................ 6
6 LDP Point-to-Multipoint LSPs on a LAN ................. 10
7 IANA Considerations ................................... 12
7.1 LDP TLVs .............................................. 12
7.2 Interface Type Identifiers ............................ 12
8 Security Considerations ............................... 12
9 Acknowledgements ...................................... 13
10 References ............................................ 13
10.1 Normative References .................................. 13
10.2 Informative References ................................ 13
11 Author's Address ...................................... 14
1. Specification of requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Introduction
This document describes procedures for distributing upstream-assigned
labels [RFC5331] for Label Distribution Protocol (LDP) [RFC5036].
These procedures follow the architecture for MPLS Upstream Label
Assignment described in [RFC5331].
This document describes extensions to LDP that a Label Switching
Router (LSR) can use to advertise to its neighboring LSRs whether the
LSR supports upstream label assignment.
This document also describes extensions to LDP to distribute
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upstream-assigned labels.
The usage of MPLS upstream label assignment using LDP for avoiding
branch LSR traffic replication on a LAN for LDP point-to-multipoint
(P2MP) Label Switched Paths (LSPs) [MLDP] is also described.
3. LDP Upstream Label Assignment Capability
According to [RFC5331], upstream-assigned label bindings MUST NOT be
used unless it is known that a downstream LSR supports them. This
implies that there MUST be a mechanism to enable an LSR to advertise
to its LDP neighbor LSR(s) its support of upstream-assigned labels.
A new Capability Parameter, the LDP Upstream Label Assignment
Capability, is introduced to allow an LDP peer to exchange with its
peers, its support of upstream label assignment. This parameter
follows the format and procedures for exchanging Capability
Parameters defined in [RFC5561].
Following is the format of the LDP Upstream Label Assignment
Capability Parameter:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1|0| Upstream Lbl Ass Cap(IANA)| Length (= 1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1| Reserved |
+-+-+-+-+-+-+-+-+
If an LSR includes the Upstream Label Assignment Capability in LDP
Initialization Messages it implies that the LSR is capable of both
distributing upstream-assigned label bindings and receiving upstream-
assigned label bindings. The reserved bits MUST be set to zero on
transmission and ignored on receipt. The Upstream Label Assignment
Capability Parameter MUST be carried only in LDP initialization
messages and MUST be ignored if received in LDP Capability messages.
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4. Distributing Upstream-Assigned Labels in LDP
An optional LDP TLV, Upstream-Assigned Label Request TLV, is
introduced. To request an upstream-assigned label an LDP peer MUST
include this TLV in a Label Request message.
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|0| Upstream Ass Lbl Req (TBD)| Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
An optional LDP TLV, Upstream-Assigned Label TLV is introduced to
signal an upstream-assigned label. Upstream-Assigned Label TLVs are
carried by the messages used to advertise, release and withdraw
upstream assigned label mappings.
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|0| Upstream Ass Label (TBD) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Label field is a 20-bit label value as specified in [RFC3032]
represented as a 20-bit number in a 4 octet field as specified in
section 3.4.2.1 of RFC5036 [RFC5036].
4.1. Procedures
Procedures for Label Mapping, Label Request, Label Abort, Label
Withdraw and Label Release follow [RFC5036] other than the
modifications pointed out in this section.
A LDP LSR MUST NOT distribute the Upstream Assigned Label TLV to a
neighboring LSR if the neighboring LSR had not previously advertised
the Upstream Label Assignment Capability in its LDP Initialization
messages. A LDP LSR MUST NOT send the Upstream Assigned Label
Request TLV to a neighboring LSR if the neighboring LSR had not
previously advertised the Upstream Label Assignment Capability in its
LDP Initialization messages.
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As described in [RFC5331] the distribution of upstream-assigned
labels is similar to either ordered LSP control or independent LSP
control of the downstream assigned labels.
When the label distributed in a Label Mapping message is an upstream-
assigned label, the Upstream Assigned Label TLV MUST be included in
the Label Mapping message. When an LSR receives a Label Mapping
message with an Upstream Assigned Label TLV and it does not recognize
the TLV, it MUST generate a Notification message with a status code
of "Unknown TLV" [RFC5036]. If it does recognize the TLV but is
unable to process the upstream label, it MUST generate a Notification
message with a status code of "No Label Resources". If the Label
Mapping message was generated in response to a Label Request message,
the Label Request message MUST contain an Upstream Assigned Label
Request TLV. A LSR that generates an upstream assigned label request
to a neighbor LSR, for a given FEC, MUST NOT send a downstream label
mapping to the neighbor LSR for that FEC unless it withdraws the
upstream-assigned label binding. Similarly if an LSR generates a
downstream assigned label request to a neighbor LSR, for a given FEC,
it MUST NOT send an upstream label mapping to that LSR for that FEC,
unless it aborts the downstream assigned label request.
The Upstream Assigned Label TLV may be optionally included in Label
Withdraw and Label Release messages that withdraw/release a
particular upstream assigned label binding.
5. LDP Tunnel Identifier Exchange
As described in [RFC5331] an upstream LSR Ru MAY transmit an MPLS
packet, the top label of which (L) is upstream-assigned, to a
downstream LSR Rd, by encapsulating it in an IP or MPLS tunnel. In
this case the fact that L is upstream-assigned is determined by Rd by
the tunnel on which the packet is received. There must be a mechanism
for Ru to inform Rd that a particular tunnel from Ru to Rd will be
used by Ru for transmitting MPLS packets with upstream-assigned MPLS
labels.
When LDP is used for upstream label assignment, the Interface ID TLV
[RFC3472] is used for signaling the Tunnel Identifier. If Ru uses an
IP or MPLS tunnel to transmit MPLS packets with upstream assigned
labels to Rd, Ru MUST include the Interface ID TLV in the Label
Mapping messages along with the Upstream Assigned Label TLV. The
IPv4/v6 Next/Previous Hop Address and the Logical Interface ID fields
in the Interface ID TLV SHOULD be set to 0 by the sender and ignored
by the receiver. The Length field indicates the total length of the
TLV, i.e., 4 + the length of the value field in octets. A value
field whose length is not a multiple of four MUST be zero-padded so
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that the TLV is four- octet aligned.
Hence the IPv4 Interface ID TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0|0| Type (0x082d) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Next/Previous Hop Address (0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Logical Interface ID (0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The IPv6 Interface ID TLV 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0|0| Type (0x082e) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Next/Previous Hop Address (0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Logical Interface ID (0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
As shown in the above figures the Interface ID TLV carries sub-TLVs.
Four new Interface ID sub-TLVs are introduced to support RSVP-TE P2MP
LSPs, LDP P2MP LSPs, IP Multicast Tunnels and context labels. The
sub-TLV value in the sub-TLV acts as the tunnel identifier.
Following are the sub-TLVs that are introduced:
1. RSVP-TE P2MP LSP TLV. Type = 28 (To be assigned by IANA). Value of
the TLV is the RSVP-TE P2MP LSP SESSION Object [RFC4875].
Below is the RSVP-TE P2MP LSP TLV format when carried in the IPv4
Interface ID TLV:
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type (0x1c) | 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| P2MP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MUST be zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Below is the RSVP-TE P2MP LSP TLV format when carried in the IPv6
Interface ID TLV:
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 (0x1c) | 28 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| P2MP ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MUST be zero | Tunnel ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extended Tunnel ID |
| |
| ....... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
This TLV identifies the RSVP-TE P2MP LSP. It allows Ru to tunnel an
"inner" LDP P2MP LSP, the label for which is upstream assigned, over
an "outer" RSVP-TE P2MP LSP that has leaves <Rd1...Rdn>. The RSVP-TE
P2MP LSP IF_ID TLV allows Ru to signal to <Rd1...Rdn> the binding of
the inner LDP P2MP LSP to the outer RSVP-TE P2MP LSP. The control
plane signaling between Ru and <Rd1...Rdn> for the inner P2MP LSP
uses targeted LDP signaling messages
2. LDP P2MP LSP TLV. Type = 29 (To be assigned by IANA). Value of the
TLV is the LDP P2MP FEC as defined in [MLDP] and has to be set as per
the procedures in [MLDP]. Here is the format of the LDP P2MP FEC as
defined in [MLDP]:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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|P2MP Type | Address Family | Address Length|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Root Node Address ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Opaque Length | Opaque Value ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
~ ~
| |
| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
The Address Family MUST be set to IPv4, the Address Length MUST be
set to 4 and the Root Node Address MUST be set to an IPv4 address
when the LDP P2MP LSP TLV is carried in the IPv4 Interface ID TLV.
The Address Family MUST be set to IPv6, the Address Length MUST be
set to 16 and the Root Node Address MUST be set to an IPv6 address
when the LDP P2MP LSP TLV is carried in the IPv6 Interface ID TLV.
The TLV value identifies the LDP P2MP LSP. It allows Ru to tunnel an
"inner" LDP P2MP LSP, the label for which is upstream assigned, over
an "outer" LDP P2MP LSP that has leaves <Rd1...Rdn>. The LDP P2MP LSP
IF_ID TLV allows Ru to signal to <Rd1...Rdn> the binding of the
inner LDP P2MP LSP to the outer LDP- P2MP LSP. The control plane
signaling between Ru and <Rd1...Rdn> for the inner P2MP LSP uses
targeted LDP signaling messages
3. IP Multicast Tunnel TLV. Type = 30 (To be assigned by IANA) In
this case the TLV value is a <Source Address, Multicast Group
Address> tuple. Source Address is the IP address of the root of the
tunnel i.e. Ru, and Multicast Group Address is the Multicast Group
Address used by the tunnel. The addresses MUST be IPv4 addresses when
the IP Multicast Tunnel TLV is included in the IPv4 Interface ID TLV.
The addresses MUST be IPv6 addresses when the IP Multicast Tunnel TLV
is included in the IPv6 Interface ID TLV.
4. MPLS Context Label TLV. Type = 31 (To be assigned by IANA). In
this case the TLV value is a <Source Address, MPLS Context Label>
tuple. The Source Address belongs to Ru and the MPLS Context Label is
an upstream assigned label, assigned by Ru. The Source Address MUST
be set to an IPv4 address when the MPLS Context Label TLV is carried
in the IPv4 Interface ID TLV. The Source Address MUST be set to an
IPv6 address when the MPLS Context Label TLV is carried in the IPv6
Interface ID TLV. This allows Ru to tunnel an "inner" LDP P2MP LSP,
the label of which is upstream assigned, over an "outer" one-hop MPLS
LSP, where the outer one-hop LSP has the following property:
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+ The label pushed by Ru for the outer MPLS LSP is an upstream
assigned context label, assigned by Ru. When <Rd1...Rdn> perform
an MPLS label lookup on this label a combination of this label
and the incoming interface MUST be sufficient for <Rd1...Rdn> to
uniquely determine Ru's context specific label space to lookup
the next label on the stack in. <Rd1...Rdn> MUST receive the data
sent by Ru with the context specific label assigned by Ru being
the top label on the label stack.
Currently the usage of the context label TLV is limited only to LDP
P2MP LSPs on a LAN as specified in the next section. The context
label TLV MUST NOT be used for any other purposes.
Note that when the outer P2MP LSP is signaled with RSVP-TE or MLDP
the above procedures assume that Ru has a priori knowledge of all the
<Rd1, ... Rdn>. In the scenario where the outer P2MP LSP is signaled
using RSVP-TE, Ru can obtain this information from RSVP-TE. However,
in the scenario where the outer P2MP LSP is signaled using MLDP, MLDP
does not provide this information to Ru. In this scenario the
procedures by which Ru could acquire this information are outside the
scope of this document.
6. LDP Point-to-Multipoint LSPs on a LAN
This section describes one application of upstream label assignment
using LDP. Further applications are to be described in separate
documents.
[MLDP] describes how to setup P2MP LSPs using LDP. On a LAN the
solution relies on "ingress replication". A LSR on a LAN, that is a
branch LSR for a P2MP LSP, (say Ru) sends a separate copy of a packet
that it receives on the P2MP LSP to each of the downstream LSRs on
the LAN (say <Rd1...Rdn> that are adjacent to it in the P2MP LSP.
It is desirable for Ru to send a single copy of the packet for the
LDP P2MP LSP on the LAN, when there are multiple downstream routers
on the LAN that are adjacent to Ru in that LDP P2MP LSP. This
requires that each of <Rd1...Rdn> must be able to associate the label
L, used by Ru to transmit packets for the P2MP LSP on the LAN, with
that P2MP LSP. It is possible to achieve this using LDP upstream-
assigned labels with the following procedures.
Consider an LSR Rd that receives the LDP P2MP FEC [MLDP] from its
downstream LDP peer. Further the upstream interface to reach LSR Ru
which is the next-hop to the P2MP LSP root address, Pr, in the LDP
P2MP FEC, is a LAN interface, Li. Further Rd and Ru support upstream-
assigned labels. In this case Rd instead of sending a Label Mapping
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message as described in [MLDP] sends a Label Request message to Ru.
This Label Request message MUST contain an Upstream Assigned Label
Request TLV.
On receiving this message, Ru sends back a Label Mapping message to
Rd with an upstream-assigned label. This message also contains an
Interface ID TLV with a MPLS Context Label sub-TLV, as described in
the previous section, with the value of the MPLS label set to a value
assigned by Ru on inteface Li as specified in [RFC5331]. Processing
of the Label Request and Label Mapping messages for LDP upstream-
assigned labels is as described in section 4.1. If Ru receives a
Label Request for an upstream assigned label for the same P2MP FEC
from multiple downstream LSRs on the LAN, <Rd1...Rdn>, it MUST send
the same upstream-assigned label to each of <Rd1...Rdn>.
Ru transmits the MPLS packet using the procedures defined in
[RFC5331] and [RFC5332]. The MPLS packet transmitted by Ru contains
as the top label the context label assigned by Ru on the LAN
interface, Li. The bottom label is the upstream label assigned by Ru
to the LDP P2MP LSP. The top label is looked up in the context of the
LAN interface, Li, [RFC5331] by a downstream LSR on the LAN. This
lookup enables the downstream LSR to determine the context specific
label space to lookup the inner label in.
Note that <Rd1...Rdn> may have more than one equal cost next-hop on
the LAN to reach Pr. It MAY be desirable for all of them to send the
label request to the same upstream LSR and they MAY select one
upstream LSR using the following procedure:
1. The candidate upstream LSRs are numbered from lower to higher IP
address
2. The following hash is performed: H = (Sum Opaque value) modulo N,
where N is the number of candidate upstream LSRs. Opaque value is
defined in [MLDP] and comprises the P2MP LSP identifier.
3. The selected upstream LSR U is the LSR that has the number H.
This allows for load balancing of a set of LSPs among a set of
candidate upstream LSRs, while ensuring that on a LAN interface a
single upstream LSR is selected. It is also to be noted that the
procedures in this section can still be used by Rd and Ru if other
LSRs on the LAN do not support upstream label assignment. Ingress
replication and downstream label assignment will continue to be used
for LSRs that do not support upstream label assignment.
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7. IANA Considerations
7.1. LDP TLVs
IANA maintains a registry of LDP TLVs at the registry "Label
Distribution Protocol" in the sub-registry called "TLV Type Name
Space".
This document defines a new LDP Upstream Label Assignment Capability
TLV (Section 3). IANA is requested to assign the value 0x0507 to this
TLV.
This document defines a new LDP Upstream-Assigned Label TLV (Section
4). IANA is requested to assign the type value of 0x204 to this TLV.
This document defines a new LDP Upstream-Assigned Label Request TLV
(Section 4). IANA is requested to assign the type value of 0x205 to
this TLV.
7.2. Interface Type Identifiers
[RFC3472] defines the LDP Interface ID IPv4 and IPv6 TLV. These top-
level TLVs can carry sub-TLVs dependent on the interface type. These
sub-TLVs are assigned "Interface ID Types". IANA maintains a registry
of Interface ID Types for use in GMPLS in the registry "Generalized
Multi-Protocol Label Switching (GMPLS) Signaling Parameters" and sub-
registry "Interface_ID Types". IANA is requested to make
corresponding allocations from this registry as follows:
- RSVP-TE P2MP LSP TLV (requested value 28)
- LDP P2MP LSP TLV (requested value 29)
- IP Multicast Tunnel TLV (requested value 30)
- MPLS Context Label TLV (requested value 31)
8. Security Considerations
The security considerations discussed in RFC 5036, RFC 5331 and RFC
5332 apply to this document.
More detailed discussion of security issues that are relevant in the
context of MPLS and GMPLS, including security threats, related
defensive techniques, and the mechanisms for detection and reporting,
are discussed in "Security Framework for MPLS and GMPLS Networks
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[MPLS-SEC].
9. Acknowledgements
Thanks to Yakov Rekhter for his contribution. Thanks to Ina Minei and
Thomas Morin for their comments. The hashing algorithm used on LAN
interfaces is taken from [MLDP]. Thanks to Loa Andersson, Adrian
Farrel and Eric Rosen for their comments and review.
10. References
10.1. Normative References
[RFC5331] R. Aggarwal, Y. Rekhter, E. Rosen, "MPLS Upstream Label
Assignment and Context Specific Label Space", RFC5331
[RFC5332] T. Eckert, E. Rosen, R. Aggarwal, Y. Rekhter, RFC5332
[RFC2119] "Key words for use in RFCs to Indicate Requirement
Levels.", Bradner, March 1997
[RFC5036] L. Andersson, et. al., "LDP Specification", RFC5036.
[RFC4875] R. Aggarwal, D. Papadimitriou, S. Yasukawa [Editors],
"Extensions to RSVP-TE for Point to Multipoint TE LSPs", RFC 4875
[MLDP] I. Minei et. al, "Label Distribution Protocol Extensions for
Point-to-Multipoint and Multipoint-to-Multipoint Label Switched
Paths", draft-ietf-mpls-ldp-p2mp-08.txt
10.2. Informative References
[RFC5561] B. Thomas, K. Raza, S. Aggarwal, R. Aggarwal, JL. Le Roux,
"LDP Capabilities", RFC5561
[MPLS-SEC] L. fang, ed, "Security Framework for MPLS and GMPLS
Networks", draft-ietf-mpls-mpls-and-gmpls-security-framework-07.txt
[RFC3032] E. Rosen et. al, "MPLS Label Stack Encoding", RFC 3032
[RFC3472] Ashwood-Smith, P. and L. Berger, Editors, " Generalized
Multi-Protocol Label Switching (GMPLS) Signaling - Constraint-based
Routed Label Distribution Protocol (CR-LDP) Extensions", RFC 3472,
January 2003.
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11. Author's Address
Rahul Aggarwal
Juniper Networks
1194 North Mathilda Ave.
Sunnyvale, CA 94089
Phone: +1-408-936-2720
Email: rahul@juniper.net
Jean-Louis Le Roux
France Telecom
2, avenue Pierre-Marzin
22307 Lannion Cedex
France
E-mail: jeanlouis.leroux@orange-ftgroup.com
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