Internet DRAFT - draft-wijnands-mpls-mldp-node-protection
draft-wijnands-mpls-mldp-node-protection
Network Working Group IJ. Wijnands, Ed.
Internet-Draft E. Rosen
Intended status: Standards Track K. Raza
Expires: December 25, 2013 Cisco Systems, Inc.
J. Tantsura
Ericsson
A. Atlas
Juniper Networks
Q. Quintin
Huawei Technology
June 23, 2013
mLDP Node Protection
draft-wijnands-mpls-mldp-node-protection-04
Abstract
This document describes procedures to support node protection for
Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths
(MP LSPs) built by LDP ("Label Distribution Protocol"), or simply
mLDP. In order to protect a node N, the Point of Local Repair (PLR)
LSR of N must learn the Merge Point (MPT) LSR(s) of node N such that
traffic can be redirected to them in case node N fails. Redirecting
the traffic around the failed node N depends on existing P2P LSPs
originated from the PLR LSR to the MPT LSRs while bypassing LSR node
N.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on December 25, 2013.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions used in this document . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. PLR Determination . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Transit node procedure . . . . . . . . . . . . . . . . . . 4
2.2. MP2MP root node procedure . . . . . . . . . . . . . . . . 5
2.3. PLR information encoding . . . . . . . . . . . . . . . . . 5
3. Using the tLDP session . . . . . . . . . . . . . . . . . . . . 7
4. Link or node failure . . . . . . . . . . . . . . . . . . . . . 9
4.1. Re-convergence after node/link failure . . . . . . . . . . 10
4.1.1. Node failure . . . . . . . . . . . . . . . . . . . . . 10
4.1.2. Link failure . . . . . . . . . . . . . . . . . . . . . 10
4.1.3. Switching to new primary path . . . . . . . . . . . . 11
5. mLDP Capabilities for Node Protection . . . . . . . . . . . . 11
5.1. PLR capability . . . . . . . . . . . . . . . . . . . . . . 12
5.2. MPT capability . . . . . . . . . . . . . . . . . . . . . . 12
5.3. The Protected LSR . . . . . . . . . . . . . . . . . . . . 12
5.4. The Node Protection Capability . . . . . . . . . . . . . . 13
6. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7. IANA considerations . . . . . . . . . . . . . . . . . . . . . 14
8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 14
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.1. Normative References . . . . . . . . . . . . . . . . . . . 14
9.2. Informative References . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
This document describes procedures to support node protection for
Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths
(MP-LSPs) built by LDP ("Label Distribution Protocol"), or simply
mLDP. In order to protect a node N, the Point of Local Repair (PLR)
of N must learn the Merge Point (MPT) LSR(s) of node N such that
traffic can be redirected to them in case node N fails. Redirecting
the traffic around the failed node N depends on existing P2P LSPs
originating from the PLR LSR to the MPT LSR(s) while bypassing node
N. The procedures to setup these P2P LSPs are outside the scope of
this document, but one can imagine using RSVP-TE or LDP LFA based
techniques to accomplish this.
The solution described in this document signals the MPT LSR(s) to the
PLR LSR(s) via a Targeted LDP (tLDP) session [RFC5036]. By having a
tLDP session with the PLR, most of the (m)LDP features currently
defined should just work, like Make-Before-Break (MBB), Graceful
Restart (GR), Typed Wildcard FEC support, etc. All this is achieved
at the expense of having an additional tLDP session between an MPT
and PLR LSR.
1.1. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
The terms "node" is used to refer to an LSR and used interchangeably.
The terms "PLR" and "MPT" are used as shorthand to refer to "PLR LSR"
and "MPT LSR" respectively.
1.2. Terminology
mLDP: Multipoint extensions to LDP.
PLR: Point of Local Repair (the LSR that redirects the traffic to
one or more Merge Point LSRs).
MPT: Merge Point (the LSR that merges the backup LSP with primary
LSP. Note, there can be multiple MPT LSRs for a single MP-LSP
node protection).
tLDP: Targeted LDP session.
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MP LSP: Multi-Point LSP (either a P2MP or MP2MP LSP).
2. PLR Determination
In order for a MPT to establish a tLDP session with the PLR, it first
has to learn the PLR for a particular MP LSP. It is the
responsibility of the protected node N to advertise the PLR address
to the MPT. The PLR address for a MP LSP on node N is the address of
the upstream LDP peer, but only when node N is NOT the root node of
the MP2MP LSP. If node N is the root node, the procedures are
slightly different as described in Section 2.2. The procedures that
follow assume that all the participating nodes (N, PLRs, MPTs) are
enabled (e.g. by a user configuration) to support and implement this
feature.
2.1. Transit node procedure
Below we are describing the procedures when the protected node is a
transit node along the path to the root.
root
^
|
(LSR1)
. | .
. | .
. (N) .
. / \ .
. / \.
(LSR2) (LSR3)
| |
Figure 1.
N: The node being protected,
...: Backup LSPs from LSR1 to the LSR2 and LSR3.
Node N uses the root address of the MP LSP to determine the upstream
LSR for a given MP LSP following the procedures as documented in
[RFC6388] section 2.4.1.1. The upstream LSR in figure 1 is LSR1
because it is the first hop along the shortest path to reach the root
address. After determining the upstream LSR, node N (which is
feature enabled), MUST advertise the address of LSR1 as the PLR
address to the downstream members of the MP LSP (i.e. LSR2 and LSR3)
if the given downstream member has announced support for node
protection (see Section 5) for Capability negotiation). For the
format and encoding of PLR address information, see Section 2.3.
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2.2. MP2MP root node procedure
In this section we are describing the procedures for when the
protected node is the root of a MP2MP LSP. Consider figure 2 below;
|
(LSR1)
. | .
. | .
. (N) . root
. / \ .
. / \.
(LSR2)....(LSR3)
| |
Figure 2.
N: The MP2MP root node being protected.
...: Backup LSPs between LSR1, LSR2 and LSR3.
Assume that LSR1, LSR2 and LSR3 are all members of a MP2MP LSP for
which N is the root node. Since N is the root of the MP2MP LSP,
there is no upstream LSR and no 'single' PLR LSR for protecting node
N. In order to protect node N, all the directly connected members of
the MP2MP must participate in protecting node N by acting both as PLR
and MPT LSR. An LSR will act as MPT for traffic coming from the
other LSR(s) and it will act as PLR for traffic it is sending to the
other LSR(s). Since node N knows the members of the MP2MP LSP, it
will advertise the member list to its directly connected members,
excluding the member it is sending to. For example, node N will
advertise {LSR3,LSR1} list to LSR2 excluding LSR2 from it. Instead
of advertising a single PLR when node N is not the root, a list of
PLRs is advertised using the procedures documented in Section 2.3.
It should be noted that the MP2MP root node protection mechanism
don't replace the Root Node Redundancy (RNR) procedures as described
in [RFC6388] section 7. The node protection procedures in this draft
will help restoring traffic for the existing MP2MP LSPs after node
failure, but a new root node has to be elected eventually in order to
allow new MP2MP LSPs to be created.
2.3. PLR information encoding
The upstream LSR address is conveyed via an LDP Notification message
with MP Status, where the MP status contains a new "PLR Status Value
Element" that specifies the address of the PLR.
The new "PLR Status Value Element" is encoded as follows;
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PLR Status Element:
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 = TBA-1 | Length | Addr Family |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Addr Fam cont | Num PLR entry | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
| |
| PLR entry (0 or more) ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
Type: PLR Status Value Element (Type TBA-1 to be assigned by IANA)
Length: The Length field encodes the length of the Status Value
following the Length field. The encoded Length varies based on
the Address Family and the number of PLR entries.
Address Family: Two octet quantity containing a value from IANA's
"Address Family Numbers" registry that encodes the address family
for the PLR Address encoded in the PLR entry.
Num PLR entry: Number of "PLR entries" encoded in the Status Value
Element, followed by "Num PLR entry" field (please see format of a
PLR entry below).
The format of a "PLR Entry" is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|A| Reserved | PLR address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ PLR address (cont) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
A bit: 0 = Withdraw, 1 = Add.
Reserved: 15 bits, must be zero on transmit and ignored on receipt
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PLR address: PLR Address encoded according to Address Family field
encoded in the PLR Status Value Element.
The size of a "PLR Entry" is the 2 octets ("A bit + Reserved") + PLR
address length. The length of the PLR address is depending on the
Address Family as encoded in the PLR Status Value Element. The size
of a "PLR entry" is 6 octets and 18 octets respectively for an IPv4
PLR address and an IPv6 PLR address.
If the PLR address on N changes for a given MP LSP, N needs to
trigger a new PLR Status to update the MPT(s). A node N can
advertise or withdraw a given PLR from its PLR set by setting "A bit"
to 1 or 0 respectively in corresponding PLR entry. Removing a PLR
address is likely due to a link failure, see the procedures as
documented in Section 4.1. To remove all PLR addresses belonging to
the encoded Address Family, an LSR N MUST encode PLR Status Value
Element with no PLR entry and "Num PLR entry" field MUST be set to
zero.
Along with the PLR MP Status a MP FEC TLV MUST be included in the LDP
Notification message so that a receiver is able to associate the PLR
Status with the MP LSP.
3. Using the tLDP session
The receipt of a PLR MP Status (with PLR addresses) for a MP LSP on a
receiving LSR makes it an MPT for node protection. If not already
established, the MPT LSR MUST establish a tLDP session with all of
the learned PLR addresses using the procedures as documented in
[I-D.ietf-mpls-targeted-mldp].
Using Figure 1 as the reference topology, let us assume that both
LSR2 and LSR3 are MPTs and have established a tLDP session with the
PLR being LSR1. Assume that both LSR2 and LSR3 have a FEC <R,X> with
a upstream LSR N and label Ln assigned to FEC towards N. The MPTs
will create a secondary upstream LSR (using the received PLR address)
and assigned a Label Lpx to FEC <R,X> towards PLR for it. The MPTs
will do that for each PLR address that was learned for the MP LSP.
In this example, the MPTs will have a FEC <R,X> with two local labels
associated with it. Ln that was assigned to N via the normal mLDP
procedures, and Label Lpx that was assigned for PLR (LSR1) for the
purpose of node protecting MP LSP via node N. Note, when the
protected node is a MP2MP root node, there will be an upstream LSR
for each PLR address that was advertised along with a unique Label
Lpx.
The receipt of a FEC Label Mapping alone over the tLDP session from
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MPT on a PLR conveys the label information but does not convey the
node being protected. The information about a protected node is
known to the MPT LSR and needs to be communicated to the PLR as well.
For this reason, the FEC Label Mapping (FEC <R,X> : Lpx) sent by the
MPT over the tLDP session to the PLR MUST include a Status TLV with
MP Status including a new LDP MP status Value Element called the
"Protected Node Status Value Element". This new value element is
used to specify the address of the node being protected. The
"Protected Node Status Value Element" 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 = TBA-2 | Length | Addr Family |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Addr Fam cont | Node address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Node address continued |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type : Protected Node Status Value Element (Type TBA-2 to be
assigned by IANA)
Length: The Length field encodes the length of the Status Value
following the Length field. The encoded Length varies based on
the Address Family and is 6 octets (for Address Family + IPv4
address and 18 octets for Address Family + IPv6 address.
Address Family: Two octet quantity containing a value from IANA's
"Address Family Numbers" registry that encodes the address family
for the Node Address.
Node address: Protected node address encoded according to Address
Family field.
When a PLR receives a Label Mapping for FEC <R,X> that includes a
Protected Node Status, it will only use that label binding once the
Node advertised in the Status value becomes unreachable. If the LSP
is a MP2MP LSP, the PLR would have assigned a Label Mapping for the
upstream MP2MP FEC Element to the MPT ([RFC6388] section 3) for FEC
<R,X>. This label binding on the MPT MUST only be used once node N
becomes unreachable.
The procedures to determine if a node is unreachable is a local
decision and not spelled out in this draft. Typical link failure or
Bidirectional Forwarding Detection (BFD) can be used to determine and
detect node unreachability.
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4. Link or node failure
Consider the following topology;
root
^
|
. (LSR1)
. / | .
. (M) | .
. \ | .
. (N) .
. / \ .
. / \.
(LSR2) (LSR3)
| |
Figure 3.
N: The node being protected
M: The backup node to protect link LSR1 - N
...; Backup LSPs from LSR1 to LSR2 and LSR3.
Assume that LSR1 is the PLR for protected node N, LSR2 and LSR3 are
MPTs for node N. When LSR1 discovered that node N is unreachable, it
can't determine whether it is the 'LSR1 - N' link or node N that
failed. In Figure 3, the link between LSR1 and N is also protected
using Fast ReRoute (FRR) [RFC4090] link protection via node M. LSR1
MAY potentially invoke 2 protection mechanisms at the same time,
redirection the traffic due to link protection via node M to N, and
for node protection directly to LSR1 and LSR2. If only the link
failed, LSR2 and LSR3 will receive the packets twice due to the two
protection mechanisms. To prevent duplicate packets to be forwarded
to the receivers on the tree, LSR2 and LSR3 need to determin which
upstream node to accept the packets from. So, either from the
primary upstream LSR N or from the secondary upstream LSR1, but never
both at the same time. The selection between the primary upstream
LSR or (one or more) secondary upstream LSRs (on LSR2 and LSR3) is
based on the reachability of the protected node N. As long as N is
reachable, N is the primary upstream LSR who is accepting the MPLS
packets and forwarding them. Once N becomes unreachable, the
secondary upstream LSRs (LSR1 in our example) are activated. Note
that detecting if N is unreachable is a local decision and not
spelled out in this draft. Typical link failure or Bidirectional
Forwarding Detection (BFD) can be used to determine and detect node
unreachability.
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4.1. Re-convergence after node/link failure
Consider the following topology;
root
^
_ |
/. (LSR1)
/. /. | .\
/. (M). | .\
(P). \. | .\
\. ( N ) .(Q)
\. / \ ./
\. / \ ./
(LSR2) (LSR3)
| |
Figure 4.
N: The node being protected.
M: The backup node to protect link 'LSR1 - N'.
P and Q: The nodes on the new primary path after N failure.
...: P2P backup LSPs.
Assume that LSR1 has detected that Node N is unreachable and invoked
both the Link Protection and Node Protection procedures as described
in this draft. LSR1 is acting as PLR and sending traffic over both
the backup P2P LSP to node N (via M) and the P2P LSPs directly to
LSR2 and LSR3, acting as MPT LSRs. The sequence of events are
depending on whether the link 'LSR1 - N' has failed or node N itself.
The node's downsteam from the protected node (and participating in
node protection) MUST have the capability to determin that the
protected node became unreachable. Otherwise the procedures below
can not be applied.
4.1.1. Node failure
If node N failed, both LSR2 and LSR3 will have changed the primary
upstream LSR to the secondary upstream LSR (LSR1) due to node N being
unreachable. With that, the label bindings previously assigned to
LSR1 will be activated on the MPTs (LSR2 and LSR3) and the label
binding to N will be disabled. Traffic is now switched over the
label bindings that where installed for node protection.
4.1.2. Link failure
If the link 'LSR1 - N' has failed, both LSR2 and LSR3 will not change
the primary upstream LSR because node N is still reachable. LSR2 and
LSR3 will receive traffic over two different bindings, the primary
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label binding assigned to node N (due to link protection via node M)
as well as over the binding assigned to LSR1 for the node protection.
Since the secondary upstream LSRs have not been activated, the
traffic received due to node protection will be dropped. Node N will
re-converge and update LSR2 and LSR3 (Section 2.3) with the
information that the PLR address (LSR1) is no longer applicable and
must be removed. In response, LSR2 and LSR3 MUST sent a Label
Withdraw to LSR1 to withdraw the label binding. This will stop the
traffic being forwarded over the backup P2P LSPs for node protection.
LSR1 will respond back with a Label Release as soon as the binding
has been removed.
4.1.3. Switching to new primary path
The network will eventually re-converge and a new best path to the
root will be found by LSR2 and LSR3. LSR2 will find that P is its
new primary upstream LSR to reach the Root and LSR3 will find Q. Note
that although the current active upstream LSR can either be node N or
LSR1 (depending on link or node failure), it does not matter for the
following procedures. Both LSR2 and LSR3 SHOULD use the Make-Before-
Break (MBB) procedures as described in [RFC6388] section 8 to switch
to the new primary upstream node. As soon as the new primary
upstream LSRs P and Q are activated, a Label Withdraw message MUST be
sent to the old upstream LSR. Note that an upstream LSR switchover
from a tLDP neighbor to a directly connected LDP neighbor is no
different compared to switching between two directly connected
neighbors. After the Label Withdraw message has been received by
LSR1 or node N, forwarding will stop and a Label Release will be
sent.
When it is determined that after re-convergence there is no more
interest in the tLDP session between the MPT and the PLR, the tLDP
session MAY be taken down. It is possible that having no more
interest in the tLDP session is temporarily due to link flapping. In
order to avoid the tLDP session from flapping, it is RECOMMENDED to
apply a delay before tearing down the session. Determining the delay
is a local implementation matter.
5. mLDP Capabilities for Node Protection
In order to describe the capabilities of the participating LSRs , we
are organizing it per role in the network i.e., Point of Local Repair
(PLR), Merge Point (MPT), and Protected Node (as depicted in Fig 1).
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5.1. PLR capability
A PLR node should handle the following conditions;
1. Accept an incoming tLDP session from the MPT LSR.
2. Support the receipt of a "Protected Node Status Value Element"
status in a MP Status TLV over tLDP session.
3. Upon node failure detection, capable of switching traffic towards
one or more MPT(s) over P2P LSP (bypassing N) using the labels
previously advertised for MP LSPs over the tLDP session.
An LSR capable of performing these actions will advertise it self as
PLR capable in the Node Protection capability (see Section 5.4).
This is a unidirectional capability announced from PLR to the
protected LSR.
5.2. MPT capability
An MPT node should handle the following conditions;
1. Support the receipt of "PLR Status Value Element" in a MP Status
TLV from a protected node N.
2. Support to transmit "Protected Node Status Value Element" in a MP
Status TLV to a PLR.
A LSR capable of performing these actions will advertise itself as
the MPT capable in the Node Protection capability (see Section 5.4).
This is a unidirectional capability from MPT to the protected LSR.
5.3. The Protected LSR
A protected node should handle the following conditions;
1. Determine the PLR and MPT capability for directly connected
upstream and downstream LSRs for a given MP FEC.
2. Support transmitting of "PLR Status Value Element" in a MP Status
TLV to one or more downstream MPT LSRs.
The protected LSR does not advertise any capability for mLDP Node
Protection because it does not need to receive any of the defined MP
Status values as described above. However, the protected node does
play an important role in the signaling and setup of the node
protection. For a given FEC, the protected node can only send PLR
information to a downstream LSR if the PLR has signaled the PLR
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capability and the downstream LSR has signaled the MPT capability.
When the downstream LSR (acting as MPT) receives the PLR status, it
can implicitly infer that the advertised LSR(s) are PLR capable. The
MPT LSR can now proceed with setting up a tLDP session with the
PLR(s) and MP LSP node protection signaling.
5.4. The Node Protection Capability
We define a single capability "MP Node Protection Capability" to
announce the PLR and MPT capability.
The format of the capability parameter TLV is as follows:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| Type = TBA-3 | Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| Reserved |P|M| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Where
U/F bits: MUST be set to 1 and 0 respectively (as per [RFC5561])
Type: MP Node Protection Capability (Type = TBA-3 to be assigned
by IANA)
Length: MUST be set to 2.
S bit: Set to 1 to announce and 0 to withdraw the capability (as
per [RFC5561])
P bit: PLR capable for MP LSP node protection
M bit: MPT capable for MP LSP node protection
Reserved: Must be zero on transmit and ignored on receipt
The above capability can be sent in an LDP Initialization message to
announce capability at the session establishment time, or it can be
sent in LDP Capability message to dynamically update (announce or
withdraw) its capability towards its peer using procedures specified
in [RFC5561].
An LSR that supports the PLR functionality LSR MAY send this
capability to its downstream MP peers with "P" bit set; whereas, an
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LSR that supports an the MPT functionality MAY send this capability
to its upstream peer with "M" bit set. Moreover, an LSR that
supports both the PLR and MPT functionality MAY sent this capability
to its peers with both "P" and "M" bit set.
6. Security Considerations
The same security considerations apply as those for the base mLDP
specification, as described in [RFC6388].
7. IANA considerations
IANA is requested to allocate two new code points from the "LDP MP
Status Value Element type" registry within the Label Distribution
Protocol (LDP) Parameters;
Value | Name | Reference
------+----------------------------------------+-----------
TBA-1 | PLR Status Value Element | this doc
------+----------------------------------------+-----------
TBA-2 | Protected Node Status Value Element | this doc
IANA is requested to assign a new code points for a new Capability
Parameter TLV. The code point should be assigned from the IETF
Consensus range of the "TLV Type Name Space" registry within the LDP
Parameters. The lowest available new code point after 0x0970 should
be used.
Value | Description | Reference | Notes/Reg Date
------+-------------------------------+-----------+---------------
TBA-3 | MP Node Protection Capability | This doc |
8. Acknowledgments
The authors like to thank Nagendra Kumar, Duan Hong, Martin
Vigoureux, Kenji Fujihira and Loa Andersson for their comments on
this draft.
9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
Wijnands, et al. Expires December 25, 2013 [Page 14]
Internet-Draft mLDP Node Protection June 2013
[RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP
Specification", RFC 5036, October 2007.
[RFC6388] Wijnands, IJ., Minei, I., Kompella, K., and B. Thomas,
"Label Distribution Protocol Extensions for Point-to-
Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, November 2011.
[RFC5561] Thomas, B., Raza, K., Aggarwal, S., Aggarwal, R., and JL.
Le Roux, "LDP Capabilities", RFC 5561, July 2009.
[I-D.ietf-mpls-targeted-mldp]
Napierala, M. and E. Rosen, "Using LDP Multipoint
Extensions on Targeted LDP Sessions",
draft-ietf-mpls-targeted-mldp-01 (work in progress),
January 2013.
9.2. Informative References
[RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
May 2005.
Authors' Addresses
IJsbrand Wijnands (editor)
Cisco Systems, Inc.
De kleetlaan 6a
Diegem 1831
Belgium
Email: ice@cisco.com
Eric Rosen
Cisco Systems, Inc.
1414 Massachusetts Avenue
Boxborough MA 01719
USA
Email: erosen@cisco.com
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Kamran Raza
Cisco Systems, Inc.
2000 Innovation Drive
Ottawa Ontario K2K-3E8
Canada
Email: skraza@cisco.com
Jeff Tantsura
Ericsson
300 Holger Way
San Jose CA 95134
USA
Email: jeff.tantsura@ericsson.com
Alia Atlas
Juniper Networks
10 Technology Park Drive
Westford MA 01886
USA
Email: akatlas@juniper.net
Quintin Zhao
Huawei Technology
125 Nagog Technology Park
Acton MA 01719
USA
Email: quintin.zhao@huawei.com
Wijnands, et al. Expires December 25, 2013 [Page 16]
