Internet Engineering Task Force H. Chen, Ed.
Internet-Draft Huawei Technologies
Intended status: Standards Track R. Torvi, Ed.
Expires: August 18, 2014 Juniper Networks
February 14, 2014
Extensions to RSVP-TE for LSP Ingress Local Protection
draft-chen-mpls-p2mp-ingress-protection-11.txt
Abstract
This document describes extensions to Resource Reservation Protocol -
Traffic Engineering (RSVP-TE) for locally protecting the ingress node
of a Traffic Engineered (TE) Label Switched Path (LSP) in a Multi-
Protocol Label Switching (MPLS) and Generalized MPLS (GMPLS) network.
Status of this Memo
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This Internet-Draft will expire on August 18, 2014.
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Table of Contents
1. Co-authors . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. An Example of Ingress Local Protection . . . . . . . . . . 3
2.2. Ingress Local Protection with FRR . . . . . . . . . . . . 4
3. Ingress Failure Detection . . . . . . . . . . . . . . . . . . 4
3.1. Backup and Source Detect Failure . . . . . . . . . . . . . 4
3.2. Backup Detects Failure . . . . . . . . . . . . . . . . . . 5
3.3. Source Detects Failure . . . . . . . . . . . . . . . . . . 5
3.4. Next Hops Detect Failure . . . . . . . . . . . . . . . . . 5
3.5. Comparing Different Detection Modes . . . . . . . . . . . 6
4. Backup Forwarding State . . . . . . . . . . . . . . . . . . . 6
4.1. Forwarding State for Backup LSP . . . . . . . . . . . . . 7
4.2. Forwarding State on Next Hops . . . . . . . . . . . . . . 7
5. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 7
5.1. INGRESS_PROTECTION Object . . . . . . . . . . . . . . . . 8
5.1.1. Subobject: Backup Ingress IPv4/IPv6 Address . . . . . 10
5.1.2. Subobject: Ingress IPv4/IPv6 Address . . . . . . . . . 11
5.1.3. Subobject: Traffic Descriptor . . . . . . . . . . . . 11
5.1.4. Subobject: Label-Routes . . . . . . . . . . . . . . . 12
6. Behavior of Ingress Protection . . . . . . . . . . . . . . . . 13
6.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 13
6.1.1. Relay-Message Method . . . . . . . . . . . . . . . . . 13
6.1.2. Proxy-Ingress Method . . . . . . . . . . . . . . . . . 13
6.1.3. Comparing Two Methods . . . . . . . . . . . . . . . . 14
6.2. Ingress Behavior . . . . . . . . . . . . . . . . . . . . . 15
6.2.1. Relay-Message Method . . . . . . . . . . . . . . . . . 15
6.2.2. Proxy-Ingress Method . . . . . . . . . . . . . . . . . 16
6.3. Backup Ingress Behavior . . . . . . . . . . . . . . . . . 17
6.3.1. Backup Ingress Behavior in Off-path Case . . . . . . . 17
6.3.2. Backup Ingress Behavior in On-path Case . . . . . . . 20
6.3.3. Failure Detection . . . . . . . . . . . . . . . . . . 21
6.4. Merge Point Behavior . . . . . . . . . . . . . . . . . . . 21
6.5. Revertive Behavior . . . . . . . . . . . . . . . . . . . . 22
6.5.1. Revert to Primary Ingress . . . . . . . . . . . . . . 22
6.5.2. Global Repair by Backup Ingress . . . . . . . . . . . 23
7. Security Considerations . . . . . . . . . . . . . . . . . . . 23
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 24
10. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 25
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
11.1. Normative References . . . . . . . . . . . . . . . . . . . 25
11.2. Informative References . . . . . . . . . . . . . . . . . . 26
A. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 26
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1. Co-authors
Ning So, Autumn Liu, Alia Atlas, Yimin Shen, Fengman Xu, Mehmet Toy,
Lei Liu
2. Introduction
For MPLS LSPs it is important to have a fast-reroute method for
protecting its ingress node as well as transit nodes. This is not
covered either in the fast-reroute method defined in [RFC4090] or in
the P2MP fast-reroute extensions to fast-reroute in [RFC4875].
An alternate approach to local protection (fast-reroute) is to use
global protection and set up a second backup LSP (whether P2MP or
P2P) from a backup ingress to the egresses. The main disadvantage of
this is that the backup LSP may reserve additional network bandwidth.
This specification defines a simple extension to RSVP-TE for local
protection of the ingress node of a P2MP or P2P LSP.
2.1. An Example of Ingress Local Protection
Figure 1 shows an example of using a backup P2MP LSP to locally
protect the ingress of a primary P2MP LSP, which is from ingress R1
to three egresses: L1, L2 and L3. The backup LSP is from backup
ingress Ra to the next hops R2 and R4 of ingress R1.
[R2]******[R3]*****[L1]
* | **** Primary LSP
* | ---- Backup LSP
* / .... BFD Session
* / $ Link
[R1]*******[R4]****[R5]*****[L2] $
$ . / / * $
$ . / / *
[S] . / / *
$ . / / *
$ ./ / *
[Ra]----[Rb] [L3]
Figure 1: Backup P2MP LSP for Locally Protecting Ingress
Source S may send the traffic simultaneously to both primary ingress
R1 and backup ingress Ra. R1 imports the traffic into the primary
LSP. Ra normally does not put the traffic into the backup LSP.
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Ra should be able to detect the failure of R1 and switch the traffic
within 10s of ms. The exact method by which Ra does so is out of
scope. Different options are discussed in this draft.
When Ra detects the failure of R1, it imports the traffic from S into
the backup LSP to R1's next hops R2 and R4, where the traffic is
merged into the primary LSP, and then sent to egresses L1, L2 and L3.
Note that the backup egress must be one logical hop away from the
ingress. A logical hop is a direct link or a tunnel such as a GRE
tunnel, over which RSVP-TE messages may be exchanged.
2.2. Ingress Local Protection with FRR
Through using the ingress local protection and the FRR, we can
locally protect the ingress node, all the links and the intermediate
nodes of an LSP. The traffic switchover time is within tens of
milliseconds whenever the ingress, any of the links and the
intermediate nodes of the LSP fails.
The ingress node of the LSP can be locally protected through using
the ingress local protection. All the links and all the intermediate
nodes of the LSP can be locally protected through using the FRR.
3. Ingress Failure Detection
Exactly how the failure of the ingress (e.g. R1 in Figure 1) is
detected is out of scope for this document. However, it is necessary
to discuss different modes for detecting the failure because they
determine what must be signaled and what is the required behavior for
the traffic source, backup ingress, and merge-points.
3.1. Backup and Source Detect Failure
Backup and Source Detect Failure or Backup-Source-Detect for short
means that both the backup ingress and the source are concurrently
responsible for detecting the failures of the primary ingress.
In normal operations, the source sends the traffic to the primary
ingress. It switches the traffic to the backup ingress when it
detects the failure of the primary ingress.
The backup ingress does not import any traffic from the source into
the backup LSP in normal operations. When it detects the failure of
the primary ingress, it imports the traffic from the source into the
backup LSP to the next hops of the primary ingress, where the traffic
is merged into the primary LSP.
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Note that the source may locally distinguish between the failure of
the primary ingress and that of the link between the source and the
primary ingress. When the source detects the failure of the link, it
may continue to send the traffic to the primary ingress via another
link between the source and the primary ingress if there is one.
3.2. Backup Detects Failure
Backup Detects Failure or Backup-Detect means that the backup ingress
is responsible for detecting the failure of the primary ingress of an
LSP. The source SHOULD send the traffic simultaneously to both the
primary ingress and backup ingress.
The backup ingress does not import any traffic from the source into
the backup LSP in normal operations. When it detects the failure of
the primary ingress, it imports the traffic from the source into the
backup LSP to the next hops of the primary ingress, where the traffic
is merged into the primary LSP.
Note that the backup ingress may locally distinguish between the
failure of the primary ingress and that of the link between the
backup ingress and the primary ingress through two BFDs between the
backup ingress and the primary ingress. One is through the link, and
the other is not. If the first BFD is down and the second is up, the
link fails and the primary ingress does not.
3.3. Source Detects Failure
Source Detects Failure or Source-Detect means that the source is
responsible for detecting the failure of the primary ingress of an
LSP. The backup ingress is ready to import the traffic from the
source into the backup LSP after the backup LSP is up.
In normal operations, the source sends the traffic to the primary
ingress. When the source detects the failure of the primary ingress,
it switches the traffic to the backup ingress, which delivers the
traffic to the next hops of the primary ingress through the backup
LSP, where the traffic is merged into the primary LSP.
3.4. Next Hops Detect Failure
Next Hops Detect Failure or Next-Hop-Detect means that each of the
next hops of the primary ingress of an LSP is responsible for
detecting the failure of the primary ingress.
In normal operations, the source sends the traffic to both the
primary ingress and the backup ingress. Both ingresses deliver the
traffic to the next hops of the primary ingress. Each of the next
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hops selects the traffic from the primary ingress and sends the
traffic to the destinations of the LSP.
When each of the next hops detects the failure of the primary
ingress, it switches to receive the traffic from the backup ingress
and then sends the traffic to the destinations.
3.5. Comparing Different Detection Modes
+----------+--------------+----------------+--------+-------------------+
|\_Behavior|Traffic Always|Backup Ingress |Next-Hop|Incorrect Failure |
| \______ |Sent to |Activation of |Select |Detection Cause |
|Detection\|Backup Ingress|Forwarding Entry|Stream |Traffic Duplication|
|Mode | | | |(Ingress does FRR) |
+----------+--------------+----------------+--------+-------------------+
|Backup- | | | | |
|Source- | No | Yes | No | No |
|Detect | | | | |
+----------+--------------+----------------+--------+-------------------+
|Backup- | Yes | Yes | No | Yes |
|Detect | | | | |
+----------+--------------+----------------+--------+-------------------+
|Source- | No | No | No | No |
|Detect | | (Always Active)| | |
+----------+--------------+----------------+--------+-------------------+
|Next-Hop- | Yes | No | Yes |(If Ingress-Next- |
|Detect | | (Always Active)| |Hop link fails, |
| | | | |stream selection |
| | | | |at Next-Next-Hops |
| | | | |can mitigate) |
+----------+--------------+----------------+--------+-------------------+
A primary goal of failure detection and FRR protection is to avoid
traffic duplication, particularly along the P2MP. A reasonable
assumption when this ingress protection is in use is that the ingress
is also trying to provide link and node protection. When the failure
cannot be accurately identified as that of the ingress, this can lead
to the ingress sending traffic on bypass to the next-next-hop(s) for
node-protection while the backup ingress is sending traffic to its
next-hop(s) if Next-Hop-Detect mode is used. RSVP Path messages from
the bypass may help to eventually resolve this by removing the
forwarding entry for receiving the traffic from the next-hop.
4. Backup Forwarding State
Before the primary ingress fails, the backup ingress is responsible
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for creating the necessary backup LSPs to the next hops of the
ingress. These LSPs might be multiple bypass P2P LSPs that avoid the
ingress. Alternately, the backup ingress could choose to use a
single backup P2MP LSP as a bypass or detour to protect the primary
ingress of a primary P2MP LSP.
The backup ingress may be off-path or on-path of an LSP. When a
backup ingress is not any node of the LSP, we call the backup ingress
is off-path. When a backup ingress is a next-hop of the primary
ingress of the LSP, we call it is on-path. If the backup ingress is
on-path, the primary forwarding state associated with the primary LSP
SHOULD be clearly separated from the backup LSP(s) state.
Specifically in Backup-Detect mode, the backup ingress will receive
traffic from the primary ingress and from the traffic source; only
the former should be forwarded until failure is detected even if the
backup ingress is the only next-hop.
4.1. Forwarding State for Backup LSP
A forwarding entry for a backup LSP is created on the backup ingress
after the LSP is set up. Depending on the failure-detection mode
(e.g., source-detect), it may be used to forward received traffic or
simply be inactive (e.g., backup-detect) until required. In either
case, when the primary ingress fails, this forwarding entry is used
to import the traffic into the backup LSP to the next hops of the
primary ingress, where the traffic is merged into the primary LSP.
The forwarding entry for a backup LSP is a local implementation
issue. In one device, it may have an inactive flag. This inactive
forwarding entry is not used to forward any traffic normally. When
the primary ingress fails, it is changed to active, and thus the
traffic from the source is imported into the backup LSP.
4.2. Forwarding State on Next Hops
When Next-Hop-Detect is used, a forwarding entry for a backup LSP is
created on each of the next hops of the primary ingress of the LSP.
This forwarding entry does not forward any traffic normally. When
the primary ingress fails, it is used to import/select the traffic
from the backup LSP into the primary LSP.
5. Protocol Extensions
A new object INGRESS_PROTECTION is defined for signaling ingress
local protection. It is backward compatible.
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5.1. INGRESS_PROTECTION Object
The INGRESS_PROTECTION object with the FAST_REROUTE object in a PATH
message is used to control the backup for protecting the primary
ingress of a primary LSP. The primary ingress MUST insert this
object into the PATH message to be sent to the backup ingress for
protecting the primary ingress. It has the following format:
Class-Num = TBD C-Type = TBD
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length (bytes) | Class-Num | C-Type |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Secondary LSP ID | Flags | Options | DM |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ (Subobjects) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Flags
0x01 Ingress local protection available
0x02 Ingress local protection in use
0x04 Bandwidth protection
Options
0x01 Revert to Ingress
0x02 Ingress-Proxy/Relay-Message
0x04 P2MP Backup
DM (Detection Mode)
0x00 Backup-Source-Detect
0x01 Backup-Detect
0x02 Source-Detect
0x03 Next-Hop-Detect
For backward compatible, the two high-order bits of the Class-Num in
the object are set as follows:
o Class-Num = 0bbbbbbb for the object in a message not on LSP path.
The entire message should be rejected and an "Unknown Object
Class" error returned.
o Class-Num = 10bbbbbb for the object in a message on LSP path. The
node should ignore the object, neither forwarding it nor sending
an error message.
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The Secondary LSP ID in the object is an LSP ID that the primary
ingress has allocated for a protected LSP tunnel. The backup ingress
will use this LSP ID to set up a new LSP from the backup ingress to
the destinations of the protected LSP tunnel. This allows the new
LSP to share resources with the old one.
The flags are used to communicate status information from the backup
ingress to the primary ingress.
o Ingress local protection available: The backup ingress sets this
flag after backup LSPs are up and ready for locally protecting the
primary ingress. The backup ingress sends this to the primary
ingress to indicate that the primary ingress is locally protected.
o Ingress local protection in use: The backup ingress sets this flag
when it detects a failure in the primary ingress. The backup
ingress keeps it and does not send it to the primary ingress since
the primary ingress is down.
o Bandwidth protection: The backup ingress sets this flag if the
backup LSPs guarantee to provide desired bandwidth for the
protected LSP against the primary ingress failure.
The options are used by the primary ingress to specify the desired
behavior to the backup ingress and next-hops.
o Revert to Ingress: The primary ingress sets this option indicating
that the traffic for the primary LSP successfully re-signaled will
be switched back to the primary ingress from the backup ingress
when the primary ingress is restored.
o Ingress-Proxy/Relay-Message: This option is set to one indicating
that Ingress-Proxy method is used. It is set to zero indicating
that Relay-Message method is used.
o P2MP Backup: This option is set to ask for the backup ingress to
use P2MP backup LSP to protect the primary ingress. Note that one
spare bit of the flags in the FAST-REROUTE object can be used to
indicate whether P2MP or P2P backup LSP is desired for protecting
an ingress and intermediate node.
The DM (Detection Mode) is used by the primary ingress to specify a
desired failure detection mode.
o Backup-Source-Detect (0x00): The backup ingress and the source are
concurrently responsible for detecting the failure involving the
primary ingress and redirecting the traffic.
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o Backup-Detect (0x01): The backup ingress is responsible for
detecting the failure and redirecting the traffic.
o Source-Detect (0x02): The source is responsible for detecting the
failure and redirecting the traffic.
o Next-Hop-Detect (0x03): The next hops of the primary ingress are
responsible for detecting the failure and selecting the traffic.
The INGRESS_PROTECTION object may contain some of the sub objects
described below.
5.1.1. Subobject: Backup Ingress IPv4/IPv6 Address
When the primary ingress of a protected LSP sends a PATH message with
an INGRESS_PROTECTION object to the backup ingress, the object may
have a Backup Ingress IPv4/IPv6 Address sub object containing an
IPv4/IPv6 address belonging to the backup ingress. The formats of
the sub object for Backup Ingress IPv4/IPv6 Address is given below:
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 | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-1 Backup Ingress IPv4 Address
Length: Total length of the subobject in bytes, including
the Type and Length fields. The Length is always 8.
Reserved: Reserved two bytes are set to zeros.
IPv4 address: A 32-bit unicast, host address.
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 | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ IPv6 address (16 bytes) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-2 Backup Ingress IPv6 Address
Length: Total length of the subobject in bytes, including
the Type and Length fields. The Length is always 20.
Reserved: Reserved two bytes are set to zeros.
IPv6 address: A 128-bit unicast, host address.
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5.1.2. Subobject: Ingress IPv4/IPv6 Address
The INGRESS_PROTECTION object in a PATH message from the primary
ingress to the backup ingress may have an Ingress IPv4/IPv6 Address
sub object containing an IPv4/IPv6 address belonging to the primary
ingress. The sub object 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 | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-3 Ingress IPv4 Address
Length: Total length of the subobject in bytes, including
the Type and Length fields. The Length is always 8.
Reserved: Reserved two bytes are set to zeros.
IPv4 address: A 32-bit unicast, host address.
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 | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ IPv6 address (16 bytes) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-4 Backup Ingress IPv6 Address
Length: Total length of the subobject in bytes, including
the Type and Length fields. The Length is always 20.
Reserved: Reserved two bytes are set to zeros.
IPv6 address: A 128-bit unicast, host address.
5.1.3. Subobject: Traffic Descriptor
The INGRESS_PROTECTION object in a PATH message from the primary
ingress to the backup ingress may have a Traffic Descriptor sub
object describing the traffic to be mapped to the backup LSP on the
backup ingress for locally protecting the primary ingress. The sub
object has the following format:
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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 | Length | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Traffic Element 1 |
~ ~
| Traffic Element n |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-5/TBD-6/TBD-7 Interface/IPv4/6 Prefix
Length: Total length of the subobject in bytes, including
the Type and Length fields.
Reserved: Reserved two bytes are set to zeros.
The Traffic Descriptor sub object may contain multiple Traffic
Elements of same type as follows.
o Interface Traffic (Type TBD-5): Each of the Traffic Elements is a
32 bit index of an interface, from which the traffic is imported
into the backup LSP.
o IPv4/6 Prefix Traffic (Type TBD-6/TBD-7): Each of the Traffic
Elements is an IPv4/6 prefix, containing an 8-bit prefix length
followed by an IPv4/6 address prefix, whose length, in bits, was
specified by the prefix length, padded to a byte boundary.
5.1.4. Subobject: Label-Routes
The INGRESS_PROTECTION object in a PATH message from the primary
ingress to the backup ingress will have a Label-Routes sub object
containing the labels and routes that the next hops of the ingress
use. The sub object 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 | Reserved (zeros) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ (Subobjects) ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD-8 Label-Routes
Length: Total length of the subobject in bytes, including
the Type and Length fields.
Reserved: Reserved two bytes are set to zeros.
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The Subobjects in the Label-Routes are copied from the Subobjects in
the RECORD_ROUTE objects contained in the RESV messages that the
primary ingress receives from its next hops for the protected LSP.
They MUST contain the first hops of the LSP, each of which is paired
with its label.
6. Behavior of Ingress Protection
6.1. Overview
There are four parts of ingress protection: 1) setting up the
necessary backup LSP forwarding state; 2) identifying the failure and
providing the fast repair (as discussed in Sections 2 and 3); 3)
maintaining the RSVP-TE control plane state until a global repair can
be done; and 4) performing the global repair(see Section 5.5).
There are two different proposed signaling approaches to obtain
ingress protection. They both use the same new INGRESS-PROTECTION
object. The object is sent in both PATH and RESV messages.
6.1.1. Relay-Message Method
The primary ingress relays the information for ingress protection of
an LSP to the backup ingress via PATH messages. Once the LSP is
created, the ingress of the LSP sends the backup ingress a PATH
message with an INGRESS-PROTECTION object with Label-Routes
subobject, which is populated with the next-hops and labels. This
provides sufficient information for the backup ingress to create the
appropriate forwarding state and backup LSP(s).
The ingress also sends the backup ingress all the other PATH messages
for the LSP with an empty INGRESS-PROTECTION object. Thus, the
backup ingress has access to all the PATH messages needed for
modification to be sent to refresh control-plane state after a
failure.
The advantages of this method include: 1) the primary LSP is
independent of the backup ingress; 2) simple; 3) less configuration;
and 4) less control traffic.
6.1.2. Proxy-Ingress Method
Conceptually, a proxy ingress is created that starts the RSVP
signaling. The explicit path of the LSP goes from the proxy ingress
to the backup ingress and then to the real ingress. The behavior and
signaling for the proxy ingress is done by the real ingress; the use
of a proxy ingress address avoids problems with loop detection.
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[ traffic source ] *** Primary LSP
$ $ --- Backup LSP
$ $ $$ Link
$ $
[ proxy ingress ] [ backup ]
[ & ingress ] |
* |
*****[ MP ]----|
Figure 2: Example Protected LSP with Proxy Ingress Node
The backup ingress must know the merge points or next-hops and their
associated labels. This is accomplished by having the RSVP PATH and
RESV messages go through the backup ingress, although the forwarding
path need not go through the backup ingress. If the backup ingress
fails, the ingress simply removes the INGRESS-PROTECTION object and
forwards the PATH messages to the LSP's next-hop(s). If the ingress
has its LSP configured for ingress protection, then the ingress can
add the backup ingress and itself to the ERO and start forwarding the
PATH messages to the backup ingress.
Slightly different behavior can apply for the on-path and off-path
cases. In the on-path case, the backup ingress is a next hop node
after the ingress for the LSP. In the off-path, the backup ingress
is not any next-hop node after the ingress for all associated sub-
LSPs.
The key advantage of this approach is that it minimizes the special
handling code requires. Because the backup ingress is on the
signaling path, it can receive various notifications. It easily has
access to all the PATH messages needed for modification to be sent to
refresh control-plane state after a failure.
6.1.3. Comparing Two Methods
+-------+-----------+------+--------+-----------------+---------+
| |Primary LSP|Simple|Config |PATH Msg from |Reuse |
|Method |Depends on | |Proxy- |Backup to primary|Some of |
| |Backup | |Ingress-|RESV Msg from |Existing |
| |Ingress | |ID |Primary to backup|Functions|
+-------+-----------+------+--------+-----------------+---------+
|Relay- | No |Yes | No | No | Yes- |
|Message| | | | | |
+-------+-----------+------+--------+-----------------+---------+
|Proxy- | Yes |Yes- | Yes | Yes | Yes |
|Ingress| | | | | |
+-------+-----------+------+--------+-----------------+---------+
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6.2. Ingress Behavior
The primary ingress must be configured with four pieces of
information for ingress protection.
o Backup Ingress Address: The primary ingress must know an IP
address for it to be included in the INGRESS-PROTECTION object.
o Failure Detection Mode: The primary ingress must know what failure
detection mode is to be used: Backup-Source-Detect, Backup-Detect,
Source-Detect, or Next-Hop-Detect.
o Proxy-Ingress-Id (only needed for Proxy-Ingress Method): The
Proxy-Ingress-Id is only used in the Record Route Object for
recording the proxy-ingress. If no proxy-ingress-id is specified,
then a local interface address that will not otherwise be included
in the Record Route Object can be used. A similar technique is
used in [RFC4090 Sec 6.1.1].
o Application Traffic Identifier: The primary ingress and backup
ingress must both know what application traffic should be directed
into the LSP. If a list of prefixes in the Traffic Descriptor
sub-object will not suffice, then a commonly understood
Application Traffic Identifier can be sent between the primary
ingress and backup ingress. The exact meaning of the identifier
should be configured similarly at both the primary ingress and
backup ingress. The Application Traffic Identifier is understood
within the unique context of the primary ingress and backup
ingress.
With this additional information, the primary ingress can create and
signal the necessary RSVP extensions to support ingress protection.
6.2.1. Relay-Message Method
To protect the ingress of an LSP, the ingress does the following
after the LSP is up.
1. Select a PATH message.
2. If the backup ingress is off-path, then send the backup ingress a
PATH message with the content from the selected PATH message and
an INGRESS-PROTECTION object; else (the backup ingress is a next
hop, i.e., on-path case) add an INGRESS-PROTECTION object into
the existing PATH message to the backup ingress (i.e., the next
hop). The INGRESS-PROTECTION object contains the Traffic-
Descriptor sub-object, the Backup Ingress Address sub-object and
the Label-Routes sub-object. The DM (Detection Mode) in the
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object is set to indicate the failure detection mode desired.
The flags is set to indicate whether a Backup P2MP LSP is
desired. If not yet allocated, allocate a second LSP-ID to be
used in the INGRESS-PROTECTION object. The Label-Routes sub-
object contains the next-hops of the ingress and their labels.
3. For each of the other PATH messages, if the node to which the
message is sent is not the backup ingress, then send the backup
ingress a PATH message with the content copied from the message
to the node and an empty INGRESS-PROTECTION object; else send the
node the message with an empty INGRESS-PROTECTION object.
6.2.2. Proxy-Ingress Method
The primary ingress is responsible for starting the RSVP signaling
for the proxy-ingress node. To do this, the following is done for
the RSVP PATH message.
1. Compute the EROs for the LSP as normal for the ingress.
2. If the selected backup ingress node is not the first node on the
path (for all sub-LSPs), then insert at the beginning of the ERO
first the backup ingress node and then the ingress node.
3. In the PATH RRO, instead of recording the ingress node's address,
replace it with the Proxy-Ingress-Id.
4. Leave the HOP object populated as usual with information for the
ingress-node.
5. Add the INGRESS-PROTECTION object to the PATH message. Allocate
a second LSP-ID to be used in the INGRESS-PROTECTION object.
Include the Backup Ingress Address (IPv4 or IPv6) sub-object and
the Traffic-Descriptor sub-object. Set the control-options to
indicate the failure detection mode desired. Set or clear the
flag indicating that a Backup P2MP LSP is desired.
6. Optionally, add the FAST-REROUTE object [RFC4090] to the Path
message. Indicate whether one-to-one backup is desired.
Indicate whether facility backup is desired.
7. The RSVP PATH message is sent to the backup node as normal.
If the ingress detects that it can't communicate with the backup
ingress, then the ingress should instead send the PATH message to the
next-hop indicated in the ERO computed in step 1. Once the ingress
detects that it can communicate with the backup ingress, the ingress
SHOULD follow the steps 1-7 to obtain ingress failure protection.
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When the ingress node receives an RSVP PATH message with an INGRESS-
PROTECTION object and the object specifies that node as the ingress
node and the PHOP as the backup ingress node, the ingress node SHOULD
check the Failure Scenario specified in the INGRESS-PROTECTION object
and, if it is not the Next-Hop-Detect, then the ingress node SHOULD
remove the INGRESS-PROTECTION object from the PATH message before
sending it out. Additionally, the ingress node must store that it
will install ingress forwarding state for the LSP rather than
midpoint forwarding.
When an RSVP RESV message is received by the ingress, it uses the
NHOP to determine whether the message is received from the backup
ingress or from a different node. The stored associated PATH message
contains an INGRESS-PROTECTION object that identifies the backup
ingress node. If the RESV message is not from the backup node, then
ingress forwarding state should be set up, and the INGRESS-PROTECTION
object MUST be added to the RESV before it is sent to the NHOP, which
should be the backup node. If the RESV message is from the backup
node, then the LSP should be considered available for use.
If the backup ingress node is on the forwarding path, then a RESV is
received with an INGRESS-PROTECTION object and an NHOP that matches
the backup ingress. In this case, the ingress node's address will
not appear after the backup ingress in the RRO. The ingress node
should set up ingress forwarding state, just as is done if the LSP
weren't ingress-node protected.
6.3. Backup Ingress Behavior
An LER determines that the ingress local protection is requested for
an LSP if the INGRESS_PROTECTION object is included in the PATH
message it receives for the LSP. The LER can further determine that
it is the backup ingress if one of its addresses is in the Backup
Ingress Address sub-object of the INGRESS-PROTECTION object. The LER
as the backup ingress will assume full responsibility of the ingress
after the primary ingress fails. In addition, the LER determines
that it is off-path if it is not a next hop of the primary ingress.
6.3.1. Backup Ingress Behavior in Off-path Case
The backup ingress considers itself as a PLR and the primary ingress
as its next hop and provides a local protection for the primary
ingress. It behaves very similarly to a PLR providing fast-reroute
where the primary ingress is considered as the failure-point to
protect. Where not otherwise specified, the behavior given in
[RFC4090] for a PLR should apply.
The backup ingress SHOULD follow the control-options specified in the
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INGRESS-PROTECTION object and the flags and specifications in the
FAST-REROUTE object. This applies to providing a P2MP backup if the
"P2MP backup" is set, a one-to-one backup if "one-to-one desired" is
set, facility backup if the "facility backup desired" is set, and
backup paths that support the desired bandwidth, and administrative-
colors that are requested.
If multiple INGRESS-PROTECTION objects have been received via
multiple PATH messages for the same LSP, then the most recent one
that specified a Traffic-Descriptor sub-object MUST be the one used.
The backup ingress creates the appropriate forwarding state based on
failure detection mode specified. For the Source-Detect and Next-
Hop-Detect, this means that the backup ingress forwards any received
identified traffic into the backup LSP tunnel(s) to the merge
point(s). For the Backup-Detect and Backup-Source-Detect, this means
that the backup ingress creates state to quickly determine the
primary ingress has failed and switch to sending any received
identified traffic into the backup LSP tunnel(s) to the merge
point(s).
When the backup ingress sends a RESV message to the primary ingress,
it should add an INGRESS-PROTECTION object into the message. It
SHOULD set or clear the flags in the object to report "Ingress local
protection available", "Ingress local protection in use", and
"bandwidth protection".
If the backup ingress doesn't have a backup LSP tunnel to all the
merge points, it SHOULD clear "Ingress local protection available".
[Editor Note: It is possible to indicate the number or which are
unprotected via a sub-object if desired.]
When the primary ingress fails, the backup ingress redirects the
traffic from a source into the backup P2P LSPs or the backup P2MP LSP
transmitting the traffic to the next hops of the primary ingress,
where the traffic is merged into the protected LSP.
In this case, the backup ingress keeps the PATH message with the
INGRESS_PROTECTION object received from the primary ingress and the
RESV message with the INGRESS_PROTECTION object to be sent to the
primary ingress. The backup ingress sets the "local protection in
use" flag in the RESV message, indicating that the backup ingress is
actively redirecting the traffic into the backup P2P LSPs or the
backup P2MP LSP for locally protecting the primary ingress failure.
Note that the RESV message with this piece of information will not be
sent to the primary ingress because the primary ingress has failed.
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If the backup ingress has not received any PATH message from the
primary ingress for an extended period of time (e.g., a cleanup
timeout interval) and a confirmed primary ingress failure did not
occur, then the standard RSVP soft-state removal SHOULD occur. The
backup ingress SHALL remove the state for the PATH message from the
primary ingress, and tear down the one-to-one backup LSPs for
protecting the primary ingress if one-to-one backup is used or unbind
the facility backup LSPs if facility backup is used.
When the backup ingress receives a PATH message from the primary
ingress for locally protecting the primary ingress of a protected
LSP, it checks to see if any critical information has been changed.
If the next hops of the primary ingress are changed, the backup
ingress SHALL update its backup LSP(s).
6.3.1.1. Relay-Message Method
When the backup ingress receives a PATH message with the INGRESS-
PROTECTION object, it examines the object to learn what traffic
associated with the LSP and what ingress failure detection mode is
being used. It determines the next-hops to be merged to by examining
the Label-Routes sub-object in the object. If the Traffic-Descriptor
sub-object isn't included, this object is considered "empty".
The backup ingress stores the PATH message received from the primary
ingress, but does NOT forward it.
The backup ingress MUST respond with a RESV to the PATH message
received from the primary ingress. If the INGRESS-PROTECTION object
is not "empty", the backup ingress SHALL send the RESV message with
the state indicating protection is available after the backup LSP(s)
are successfully established.
6.3.1.2. Proxy-Ingress Method
The backup ingress determines the next-hops to be merged to by
collecting the set of the pair of (IPv4/IPv6 sub-object, Label sub-
object) from the Record Route Object of each RESV that are closest to
the top and not the Ingress router; this should be the second to the
top pair. If a Label-Routes sub-object is included in the INGRESS-
PROTECTION object, the included IPv4/IPv6 sub-objects are used to
filter the set down to the specific next-hops where protection is
desired. A RESV message must have been received before the Backup
Ingress can create or select the appropriate backup LSP.
When the backup ingress receives a PATH message with the INGRESS-
PROTECTION object, the backup ingress examines the object to learn
what traffic associated with the LSP and what ingress failure
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detection mode is being used. The backup ingress forwards the PATH
message to the ingress node with the normal RSVP changes.
When the backup ingress receives a RESV message with the INGRESS-
PROTECTION object, the backup ingress records an IMPLICIT-NULL label
in the RRO. Then the backup ingress forwards the RESV message to the
ingress node, which is acting for the proxy ingress.
6.3.2. Backup Ingress Behavior in On-path Case
An LER as the backup ingress determines that it is on-path if one of
its addresses is a next hop of the primary ingress and the primary
ingress is not its next hop via checking the PATH message with the
INGRESS_PROTECTION object received from the primary ingress. The LER
on-path sends the corresponding PATH messages without any
INGRESS_PROTECTION object to its next hops. It creates a number of
backup P2P LSPs or a backup P2MP LSP from itself to the other next
hops (i.e., the next hops other than the backup ingress) of the
primary ingress. The other next hops are from the Label-Routes sub
object.
It also creates a forwarding entry, which sends/multicasts the
traffic from the source to the next hops of the backup ingress along
the protected LSP when the primary ingress fails. The traffic is
described by the Traffic-Descriptor.
After the forwarding entry is created, all the backup P2P LSPs or the
backup P2MP LSP is up and associated with the protected LSP, the
backup ingress sends the primary ingress the RESV message with the
INGRESS_PROTECTION object containing the state of the local
protection such as "local protection available" flag set to one,
which indicates that the primary ingress is locally protected.
When the primary ingress fails, the backup ingress sends/multicasts
the traffic from the source to its next hops along the protected LSP
and imports the traffic into each of the backup P2P LSPs or the
backup P2MP LSP transmitting the traffic to the other next hops of
the primary ingress, where the traffic is merged into protected LSP.
During the local repair, the backup ingress continues to send the
PATH messages to its next hops as before, keeps the PATH message with
the INGRESS_PROTECTION object received from the primary ingress and
the RESV message with the INGRESS_PROTECTION object to be sent to the
primary ingress. It sets the "local protection in use" flag in the
RESV message.
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6.3.3. Failure Detection
Failure detection happens much faster than RSVP, whether via a link-
level notification or BFD. As discussed, there are different modes
for detecting it. The backup ingress MUST have properly set up its
forwarding state to either always forward the specified traffic into
the backup LSP(s) for the Source-Detect and Next-Hop-Detect modes or
to swap from discarding to forwarding when a failure is detected for
the Backup-Source-Detect and Backup-Detect modes.
For facility backup LSPs, the correct inner MPLS label to use must be
determined. For the ingress-proxy method, that MPLS label comes
directly from the RRO of the RESV. For the relay-message method,
that MPLS label comes from the Label-Routes sub-object in the non-
empty INGRESS-PROTECTION object.
As described in [RFC4090], it is necessary to refresh the PATH
messages via the backup LSP(s). The Backup Ingress MUST wait to
refresh the backup PATH messages until it can accurately detect that
the ingress node has failed. An example of such an accurate
detection would be that the IGP has no bi-directional links to the
ingress node and the last change was long enough in the past that
changes should have been received (i.e., an IGP network convergence
time or approximately 2-3 seconds) or a BFD session to the primary
ingress' loopback address has failed and stayed failed after the
network has reconverged.
As described in [RFC4090 Section 6.4.3], the backup ingress, acting
as PLR, SHOULD modify - including removing any INGRESS-PROTECTION and
FAST-REROUTE objects - and send any saved PATH messages associated
with the primary LSP.
6.4. Merge Point Behavior
An LSR that is serving as a Merge Point may need to support the
INGRESS-PROTECTION object and functionality defined in this
specification if the LSP is ingress-protected where the failure
scenario is Next-Hop-Detect. An LSR can determine that it must be a
merge point if it is not the ingress, it is not the backup ingress
(determined by examining the Backup Ingress Address (IPv4 or IPv6)
sub-object in the INGRESS-PROTECTION object), and the PHOP is the
ingress node.
In that case, when the LSR receives a PATH message with an INGRESS-
PROTECTION object, the LSR MUST remove the INGRESS-PROTECTION object
before forwarding on the PATH message. If the failure scenario
specified is Next-Hop-Detect, the MP must connect up the fast-failure
detection (as configured) to accepting backup traffic received from
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the backup node. There are a number of different ways that the MP
can enforce not forwarding traffic normally received from the backup
node. For instance, first, any LSPs set up from the backup node
should not be signaled with an IMPLICIT NULL label and second, the
associated label for the ingress- protected LSP could be set to
normally discard inside that context.
When the MP receives a RESV message whose matching PATH state had an
INGRESS-PROTECTION object, the MP SHOULD add the INGRESS-PROTECTION
object to the RESV message before forwarding it. The Backup PATH
handling is as described in [RFC4090] and [RFC4875].
6.5. Revertive Behavior
Upon a failure event in the (primary) ingress of a protected LSP, the
protected LSP is locally repaired by the backup ingress. There are a
couple of basic strategies for restoring the LSP to a full working
path.
- Revert to Primary Ingress: When the primary ingress is restored,
it re-signals each of the LSPs that start from the primary
ingress. The traffic for every LSP successfully re-signaled is
switched back to the primary ingress from the backup ingress.
- Global Repair by Backup Ingress: After determining that the
primary ingress of an LSP has failed, the backup ingress computes
a new optimal path, signals a new LSP along the new path, and
switches the traffic to the new LSP.
6.5.1. Revert to Primary Ingress
If "Revert to Primary Ingress" is desired for a protected LSP, the
(primary) ingress of the LSP re-signals the LSP that starts from the
primary ingress after the primary ingress restores. When the LSP is
re-signaled successfully, the traffic is switched back to the primary
ingress from the backup ingress and redirected into the LSP starting
from the primary ingress.
It is possible that the Ingress failure was inaccurately detected,
that the Ingress recovers before the Backup Ingress does Global
Repair, or that the Ingress has the ability to take over an LSP based
on receiving the associated RESVs.
If the ingress can resignal the PATH messages for the LSP, then the
ingress can specify the "Revert to Ingress" control-option in the
INGRESS-PROTECTION object. Doing so may cause a duplication of
traffic while the Ingress starts sending traffic again before the
Backup Ingress stops; the alternative is to drop traffic for a short
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period of time.
Additionally, the Backup Ingress can set the "Revert To Ingress"
control-option as a request for the Ingress to take over.
6.5.2. Global Repair by Backup Ingress
When the backup ingress has determined that the primary ingress of
the protected LSP has failed (e.g., via the IGP), it can compute a
new path and signal a new LSP along the new path so that it no longer
relies upon local repair. To do this, the backup ingress uses the
same tunnel sender address in the Sender Template Object and uses the
previously allocated second LSP-ID in the INGRESS-PROTECTION object
of the PATH message as the LSP-ID of the new LSP. This allows the
new LSP to share resources with the old LSP.
When the backup ingress has determined that the primary ingress of
the protected LSP has failed (e.g., via the IGP), it can compute a
new path and signal a new LSP along the new path so that it no longer
relies upon local repair. To do this, the backup ingress uses the
same tunnel sender address in the Sender Template Object and uses the
previously allocated second LSP-ID in the INGRESS-PROTECTION object
of the PATH message as the LSP-ID of the new LSP. This allows the
new LSP to share resources with the old LSP. In addition, if the
Ingress recovers, the Backup Ingress SHOULD send it RESVs with the
INGRESS-PROTECTION object where either the "Force to Backup" or
"Revert to Ingress" is specified. The Secondary LSP ID should be the
unused LSP ID - while the LSP ID signaled in the RESV will be that
currently active. The Ingress can learn from the RESVs what to
signal. Even if the Ingress does not take over, the RESVs notify it
that the particular LSP IDs are in use. The Backup Ingress can
reoptimize the new LSP as necessary until the Ingress recovers.
Alternately, the Backup Ingress can create a new LSP with no
bandwidth reservation that duplicates the path(s) of the protected
LSP, move traffic to the new LSP, delete the protected LSP, and then
resignal the new LSP with bandwidth.
7. Security Considerations
In principle this document does not introduce new security issues.
The security considerations pertaining to RFC 4090, RFC 4875 and
other RSVP protocols remain relevant.
8. IANA Considerations
TBD
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9. Contributors
Renwei Li
Huawei Technologies
2330 Central Expressway
Santa Clara, CA 95050
USA
Email: renwei.li@huawei.com
Quintin Zhao
Huawei Technologies
Boston, MA
USA
Email: quintin.zhao@huawei.com
Zhenbin Li
Huawei Technologies
2330 Central Expressway
Santa Clara, CA 95050
USA
Email: zhenbin.li@huawei.com
Boris Zhang
Telus Communications
200 Consilium Pl Floor 15
Toronto, ON M1H 3J3
Canada
Email: Boris.Zhang@telus.com
Markus Jork
Juniper Networks
10 Technology Park Drive
Westford, MA 01886
USA
Email: mjork@juniper.net
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10. Acknowledgement
The authors would like to thank Rahul Aggarwal, Eric Osborne, Ross
Callon, Loa Andersson, Michael Yue, Olufemi Komolafe, Rob Rennison,
Neil Harrison, Kannan Sampath, and Ronhazli Adam for their valuable
comments and suggestions on this draft.
11. References
11.1. Normative References
[RFC1700] Reynolds, J. and J. Postel, "Assigned Numbers", RFC 1700,
October 1994.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3692] Narten, T., "Assigning Experimental and Testing Numbers
Considered Useful", BCP 82, RFC 3692, January 2004.
[RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, September 1997.
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031, January 2001.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
[RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching
(GMPLS) Signaling Resource ReserVation Protocol-Traffic
Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.
[RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
May 2005.
[RFC4461] Yasukawa, S., "Signaling Requirements for Point-to-
Multipoint Traffic-Engineered MPLS Label Switched Paths
(LSPs)", RFC 4461, April 2006.
[RFC4875] Aggarwal, R., Papadimitriou, D., and S. Yasukawa,
"Extensions to Resource Reservation Protocol - Traffic
Engineering (RSVP-TE) for Point-to-Multipoint TE Label
Switched Paths (LSPs)", RFC 4875, May 2007.
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[P2MP-FRR]
Le Roux, J., Aggarwal, R., Vasseur, J., and M. Vigoureux,
"P2MP MPLS-TE Fast Reroute with P2MP Bypass Tunnels",
draft-leroux-mpls-p2mp-te-bypass , March 1997.
11.2. Informative References
[RFC2702] Awduche, D., Malcolm, J., Agogbua, J., O'Dell, M., and J.
McManus, "Requirements for Traffic Engineering Over MPLS",
RFC 2702, September 1999.
[RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
Encoding", RFC 3032, January 2001.
Appendix A. Authors' Addresses
Huaimo Chen
Huawei Technologies
Boston, MA
USA
Email: huaimo.chen@huawei.com
Ning So
Tata Communications
2613 Fairbourne Cir.
Plano, TX 75082
USA
Email: ning.so@tatacommunications.com
Autumn Liu
Ericsson
300 Holger Way
San Jose, CA 95134
USA
Email: autumn.liu@ericsson.com
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Raveendra Torvi
Juniper Networks
10 Technology Park Drive
Westford, MA 01886
USA
Email: rtorvi@juniper.net
Alia Atlas
Juniper Networks
10 Technology Park Drive
Westford, MA 01886
USA
Email: akatlas@juniper.net
Yimin Shen
Juniper Networks
10 Technology Park Drive
Westford, MA 01886
USA
Email: yshen@juniper.net
Fengman Xu
Verizon
2400 N. Glenville Dr
Richardson, TX 75082
USA
Email: fengman.xu@verizon.com
Mehmet Toy
Comcast
1800 Bishops Gate Blvd.
Mount Laurel, NJ 08054
USA
Email: mehmet_toy@cable.comcast.com
Lei Liu
UC Davis
USA
Chen & Torvi Expires August 18, 2014 [Page 27]
Internet-Draft LSP Ingress Protection February 2014
Email: liulei.kddi@gmail.com
Chen & Torvi Expires August 18, 2014 [Page 28]
