Internet Engineering Task Force C. Jacquenet
Internet-Draft France Telecom Orange
Intended status: Informational Q. Zhao
Expires: September 13, 2012 Huawei Technology
March 12, 2012
Receiver Driven Multicast RSVP TE Requirements
draft-jacquenet-mpls-rd-p2mp-te-requirements-01.txt
Abstract
This document presents a set of requirements for the establishment
and maintenance of Receiver-Driven Point-to-Multipoint (P2MP) and
Multipoint-to-Multipoint (MP2MP) Traffic-Engineered (TE)
Multiprotocol Label Switching (MPLS) Label Switched Paths (LSPs).
Status of this Memo
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This Internet-Draft will expire on September 13, 2012.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.3. What is not covered in this doc? . . . . . . . . . . . . . 4
2. Basic Requirements . . . . . . . . . . . . . . . . . . . . . . 5
3. Leaf Driven mRSVP-TE LSP Exampls . . . . . . . . . . . . . . . 8
4. Detailed Requirements . . . . . . . . . . . . . . . . . . . . 10
4.1. Leaf Driven mRSVP-TE LSP . . . . . . . . . . . . . . . . . 10
4.2. P2MP TE LSP Establishment, Teardown, and Modification
Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . 10
4.3. Re-Optimization of Leaf Driven mRSVP-TE LSPs . . . . . . . 11
4.4. Support for LAN interfaces . . . . . . . . . . . . . . . . 11
4.5. P2MP/MP2MP MPLS Label . . . . . . . . . . . . . . . . . . 12
4.6. Advertisement of Leaf Driven mRSVP-TE Capability . . . . . 12
4.7. Scalability . . . . . . . . . . . . . . . . . . . . . . . 12
4.8. Variation of LSP Parameters . . . . . . . . . . . . . . . 14
5. In-Band Signalling . . . . . . . . . . . . . . . . . . . . . . 14
6. Backwards Compatibility . . . . . . . . . . . . . . . . . . . 14
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
9. Security Considerations . . . . . . . . . . . . . . . . . . . 15
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
10.1. Normative References . . . . . . . . . . . . . . . . . . . 15
10.2. Informative References . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
For content delivery services that rely upon the IP multicast
transmission scheme, the distribution trees are receiver-initiated.
The delivery of such services over MPLS networking infrastructures
may rely upon P2MP LSP tree structures that are currently source-
initiated, with the root of the P2MP tree being at the LSR router
directly connected to the sender ([RFC4875].
Multiparty multimedia applications are getting greater attention in
the telecom world. Such applications are QoS-demanding and can
therefore benefit from the activation of MPLS traffic engineering
capabilities that lead to the dynamic computation and establishment
of MPLS LSPs whose characteristics comply with application-specific
QoS requirements.
P2MP-RE-REQ[RFC4461] specifies the signalling requirements to setup
multipoint LSPs from source to receiver. P2MP-TE [RFC4875] defines
the procedure to setup multipoint LSPs from source to receiver.
This document presents a set of requirements specific for the dynamic
establishment and maintenance of receiver-driven P2MP-TE and MP2MP-TE
LSPs.
1.1. Motivation
IP multicast distribution trees are receiver-initiated and dynamic by
nature. IP multicast-enabled applications are also bandwidth savvy,
especially in the area of residential Live TV broadcasting services,
where several hundreds of thousands of IPTV receivers need to be
served with the appropriate level of quality. Current source-driven
P2MP LSP establishment assumes a prior knowledge of receiver(s)
location for the sake of the P2MP LSP tree structure's forwarding
efficiency. But the receiver's location information is not available
a priori for the root MPLS router to compute and establish the
relevant P2MP tree structure. In addition, with the source-driven
P2MP-TE solution, full mesh P2MP LSP tree structures need to be
established to setup a MP2MP LSP, possibly raising scalability issues
for the delivery of some multicast services, such as
videoconferencing at large scale.
From this perspective, it is believed that receiver-driven MPLS P2MP
tree structures represent the best of breed that combines the
benefits of IP multicast, receiver-driven dynamics with the benefits
of MPLS-based, QoS-guaranteed LSP path computation.
Thus, receiver-driven MPLS P2MP/MP2MP tree structure do not require
that the root of the MPLS P2MP tree structure dynamically discovers
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and maintains receiver information a priori. In addition, such a
receiver-driven approach encourages computation schemes that can take
into account the network access conditions of the receivers
(bandwidth capabilities, IPTV customer profile, etc.) for the sake of
customer's Quality of Experience (time to access an IPTV channel,
time to zap fron one channel to another, etc.).
1.2. Terminology
The following terms are used in this document:>
o Sender: Sender refers to the source of the content/payload. As in
[RFC2205].
o Receiver: Receiver refers to the Receiver of the content/payload.
As in [RFC2205].
o Upstream: The direction of a flow from a content Receiver towards
a content Sender. As defined in [RFC2205].
o Downstream: The direction of a flow from a content Sender towards
a content Receiver. As defined in [RFC2205].
o Path-Sender: The sender of the RSVP_PATH message, with NO
correlation to the directionality of the corresponding content
flow.
o Path-Receiver: The receiver of the RSVP_PATH message, with NO
correlation to the directionality of the corresponding content
flow.
o Path-Initiator: The Path-Sender that originated the RSVP_PATH
message. The Path-Initiator is a notion that differs from the
Path-Sender because an intermediate node can be a Path-Sender, and
therefore different from the node that created and initiated the
RSVP_PATH message, which is precisely the Path- Initiator.
o Path-Terminator: The Path-Receiver that does NOT propagate the
Path message. This is a notion that differs from the Path-
Receiver because an intermediate node can be a Path-Receiver.
1.3. What is not covered in this doc?
This document does not specify any requirements for the following
functions.
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o Discovery of the root node for a given P2MP/MP2MP tree structure.
o Algorithms for computing P2MP/MP2MP distribution trees.
o Hierarchical P2MP/MP2MP LSPs.
o OAM for P2MP/MP2MP LSPs.
o Inter-area and inter-AS P2MP/MP2MP TE LSPs.
o Applicability of P2MP/MP2MP MPLS TE LSPs to service scenarios.
o Specific application requirements.
o Routing protocols.
o Construction of the traffic engineering database.
o Distribution of the information used to construct the traffic
engineering database.
2. Basic Requirements
[RFC4461] specifies requirements for P2MP traffic engineering over
MPLS. It describes sender-driven P2MP traffic engineering in detail.
Those definitions and requirements are equally applicable to
receiver-driven traffic engineering in a point-to-multipoint service
environment and are therefore not repeated here.
Following are key requirements that are specific to the receiver-
driven paradigm:
REQ1: The receiver-driven P2MP/MP2MP approach must be scalable,
i.e., the dynamic computation and maintenance of P2MP/MP2MP
tree structures must be adapted to typical live TV
broadcasting services that connect several hundreds of
thousands of receivers.
REQ2: Leaves of receiver-driven P2MP/MP2MP tree structures must be
aware of the corresponding P2MP/MP2MP LSP identifiers for
tree computation and maintenance purposes.
REQ3: The receiver-driven mechanism MUST allow the dynamic addition
and removal of leaves to and from a P2MP/MP2MP tree
structure, without any restriction (provided there is network
connectivity) . It is RECOMMENDED that the corresponding
operations be leaf-initiated.
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REQ4: The dynamic addition and removal of leaves to and from a
receiver-driven P2MP/MP2MP LSP MUST not impact the
performances of the data forwarding (packet loss,
replication, delay) towards other leaves.
REQ5: The dynamic addition and removal of leaves to and from a
receiver-driven P2MP/MP2MP LSP SHOULD NOT infer any
additional processing than that on the path from the added/
removed Leaf LSR to the Branch LSR.
REQ6: A Leaf router MUST initiate RSVP PATH message towards the
root and also signal the type of the LSP.
REQ7: The destination of a L2S (Leaf-to-Source) sub-path MUST be
one of the ingress routers where multicast data sent by a
source enter the P2MP/MP2MP LSP tree structure.
REQ8: RSVP P2MP PATH messages MUST be forwarded along the path from
a given leaf to the root of the P2MP tree structure.
REQ9: RSVP P2MP RESV messages MUST be frowarded along the path from
the root to the receiver if the leaf is the MPLS router that
directly connects receivers to the corresponding receiver-
driven P2MP tree structure . Otherwise, RSVP P2MP RESV
messages will be forwarded from the PATH Terminator to the
PATH Initiator.
REQ10: A node receiving a RSVP RESV message SHOULD interpret it as a
successful resource reservation from the upstream node for
the establishment of the P2MP tree structure.
REQ11: A node receiving a RSVP RESV message SHOULD interpret it as a
successful resource reservation from the downstream node for
the establishment of the MP2MP tree structure.
REQ12: Label allocation on incoming interface MUST be done prior to
sending RSVP PATH messages upstream for P2MP tree structures.
REQ13: Label allocation on incoming interface MUST be done prior to
sending RSVP RESV messages upstream for MP2MP tree
structures.
REQ14: For P2MP LSP tree structures, a node receiving a RSVP PATH
message MUST first decide if this RSVP PATH message will make
itself a branch LSR or not. In the case that it will become
a transit LSR because of this PATH message, then it will
allocate required resources on the interface through which
the RSVP PATH message is received, before sending the RSVP
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PATH message upstream. So that the upstream node can send
traffic soon after successfully reserving resources on the
downstream link, on which the RSVP PATH message SHOULD be
received. In the case that the node is a branch or transit
node already before it receives the PATH message, then it
will allocate required resources (provided they are
available) on the interface through which the RSVP PATH
message is received, and then send the RESV message back to
the node that sent the PATH message without sending the PATH
message upstream.
REQ15: For MP2MP LSP tree structures, a node will allocate required
resources on the interface through which the RSVP PATH
message is sent, before sending the RSVP PATH message
upstream. A node receiving a RSVP PATH message MUST first
decide if this RSVP PATH message will make itself a branch
LSR or not. In the case that it will become a transit LSR
because of this PATH message, and then allocate required
resources (provided they are available) on the interface
through which the RSVP PATH message was received and will
allocate required resources on the interface through which
the RSVP PATH message is sent, before sending it upstream.
So that the downstream node can send traffic soon after
successfully reserving resources on the upstream link, on
which the RSVP PATH message SHOULD be sent. The upstream
node can then send traffic soon after successfully reserving
resources on the downstream link, on which the RSVP PATH
message SHOULD be received. In the case that the node is a
branch or transit node already before it receives the PATH
message, then it will allocate required resources on the
interface through which the RSVP PATH message is received,
and send the RESV message to the node which sent the PATH
message without sending the PATH message upstream.
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3. Leaf Driven mRSVP-TE LSP Exampls
Path Terminator/Ingress Router
+---------+
| R1 |
+-----+---+
_
\ \ /\
\ \ \ Path Message w/ Label OBJECT
Resv \ \ \ (msg2)
Message \ \ \
(msg3) \ \ \
_\/ \ \
+----------------+ Path Remerge
| R3 | Creates Branch Point
+----------------+
_ _
/ / /\ \ \ /\
/ / / \ \ \ Path Message (msg1)
Resv Message / / / msg4 \ \ \ w/ Label OBJECT
(msg6) / / / \ \ \
/ / /Path Msg \ \ \
/ / / msg5 \ \ \
\/_ / / w/Label OBJ _\/ \ \
+----------+ +---+-----+
| R4 | | R5 |
+----------+ +---------+
Path Initiator Path Initiator
Originator ID = R4 Originator ID = R5
L2S Destination = R1 L2S Destination = R1
Session = S Session = S
Figure 1: P2MP Example
Figure 1 shows that R5 is added as the first leaf of the RD P2MP TE
LSP, the message flow goes from
R5->msg1->R3->msg2->R1->msg3->R3->msg4->R5. When the leaf R4 is
added, the message flow goes from R4->msg5->R3->msg6->R4. In this
case, when R3 receives msg5, R3 finds out that the RD P2MP LSP has
already been set up for R5: therefore, R3 finds itself a branch node
for leaf R4 and R5, so it will terminate the PATH message and build
the corresponding RESV message and send it back to R4. The
association of the LSP initiated by R4 to the existing RD P2MP LSP is
determined based on the processing of the session object from the
mRSVP-TE message. This session object is further documented in
Section 2 of this draft.
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Path Terminator/Ingress Router
+---------+
| R1 |
+-----+---+
_
\ \ /\
\ \ \ Path-mp2mp Message w/ Label OBJECT
Resv \ \ \ (msg2)
Message \ \ \
(msg3) \ \ \
w/ Label OBJECT _\/ \ \
+----------------+ Path-mp2mp
| R3 | (Branch Point)
+----------------+
_ _
/ / /\ \ \ /\
/ / / \ \ \ Path-mp2mp Message (msg1)
Resv Message / / / msg4 \ \ \ (msg1)
(msg6) / / / \ \ \ w/ Label OBJECT
w/ Label OBJECT/ / /Path-mp2mp \ \ \
/ / / Message \ \ \
/ / / (msg5) \ \ \
\/_ / / w/ Label OBJ _\/ \ \
+----------+ +---+-----+
| R4 | | R5 |
+----------+ +---------+
Path-mp2mp Initiator Path-mp2mp Initiator
Originator ID = R4 Originator ID = R5
L2S Destination = R1 L2S Destination = R1
Session = S Session = S
Figure 2: MP2MP Example
Figure 2 shows that R5 is added as the first leaf (as both a sender
and a receiver) of the RD MP2MP TE LSP, the message flow goes from
R5->msg1->R3->msg2->R1->msg3->R3->msg4->R5. When the leaf R4 (both
receiver and sender)is added, the message flow goes from
R4->msg5->R3->msg6. In this case, when R3 receives msg5, R3 finds
out that the RD MP2MP LSP has already been set up for R5, and R3 will
become the branch LSR for the leaf R4 and R5, so it will terminate
the PATH message, build a RESV message and send the RESV message back
to R4. The association of the LSP initiated by R4 to the existing
MP2MP LSP is determined based on the processing of the session object
from the mRSVP-TE message. This session object is further documented
in Section 2 of this draft.
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4. Detailed Requirements
4.1. Leaf Driven mRSVP-TE LSP
The Receiver-Driven RSVP-TE extensions MUST be applicable to the
signaling of P2MP LSPs for different switching types. For example,
it MUST be possible to signal a P2MP/MP2MP TE LSP in any switching
medium, whether it is packet or non-packet based (including frame,
cell, TDM, lambda, etc.).
As with P2P MPLS technology [RFC3031], a given traffic is associated
with a FEC in this extension. All packets that belong to a
particular FEC and that travel from a particular node MUST follow the
same Receiver- Driven P2MP/MP2MP tree structure.
In order to scale to a large number of branches, P2MP/MP2MP TE LSPs
SHOULD be identified by a unique identifier (the P2MP/MP2MP ID) that
is constant for the whole LSP regardless of the number of branches
and/or leaves.
4.2. P2MP TE LSP Establishment, Teardown, and Modification Mechanisms
The Receiver-Driven P2MP LSP approach MUST support the dynamic
establishment, maintenance, and teardown of Receiver-Driven P2MP/
MP2MP LSPs in a manner that the scalability is not affected by the
number of leaves, and it is scalable in a linear way to the number of
branches for a node. This MUST imply the ability to compute to
compute multiple P2MP tree structures at once, and to compute P2MP/
MP2MP LSP tree structures are that composed of many leaves, i.e.,
within the magnitude of typical Live TV broadcasting designs that
accommodate several hundreds of thousands of receivers.
In addition to signaling capabilities for P2MP/MP2MP LSP
establishment and teardown, the solution SHOULD support capabilities
that allow the dynamic modification of part of a given P2MP/MP2MP
tree structure without altering the whole structure:
For the purpose of adding sub-P2MP TE LSPs to an existing P2MP/MP2MP
TE LSP, the extensions SHOULD support a grafting mechanism. For the
purpose of deleting a sub-P2MP TE LSP from an existing P2MP/MP2MP TE
LSP, the extensions SHOULD support a pruning mechanism.
It is RECOMMENDED that these grafting and pruning operations cause no
additional processing in nodes that are not along the path from the
grafting or pruning node to the upstream branch node. Moreover, both
grafting and pruning operations MUST NOT disrupt the forwarding of
traffic along the P2MP/MP2MP tree at any given time.
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There is no assumption that the explicitly routed P2MP/MP2MP LSP
remains on an optimal path after several grafts and prunes have
occurred. In this context, scalability considerations refer to the
signaling process for the P2MP/MP2MP TE LSP . The TE nature of the
LSP allows that re- optimization may take place from time to time to
restore the optimality of the LSP.
4.3. Re-Optimization of Leaf Driven mRSVP-TE LSPs
The detection of a more optimal path (for example, one with a lower
overall cost) is an example of a situation where re-routing of the
Receiver-Driven P2MP/MP2MP LSP may be required. While re-routing is
in progress, an important requirement is to avoid double bandwidth
reservation (over the common parts between the old and new LSP)
through the use of resource sharing.
A Make-before-break design MUST be supported for Receiver-Driven
P2MP/MP2MP LSPs to ensure that there is minimal traffic disruption
during the re-routing operations.
Make-before-break that only applies to a sub-P2MP tree without
impacting the data on all the other parts of the P2MP tree MUST be
supported.
The solution SHOULD allow for make-before-break re-optimization of
any subdivision of the P2MP LSP. It SHOULD do so by not having any
signaling impact on the rest of the P2MP LSP, and without affecting
the ability of the management plane to manage the LSP.
The solution SHOULD also provide the ability for any downstream LSR
to have control over the re-optimization process .
Where sub-LSP re-optimization is allowed by the ingress LSR, such re-
optimization MAY be initiated by a downstream LSR that is the root of
the sub-LSP to be re-optimized. Sub-LSP re-optimization initiated by
a downstream LSR MUST be carried out with the same regard to
minimizing the impact on active traffic as mentioned above for other
re-optimization purposes.
4.4. Support for LAN interfaces
Receiver-Driven P2MP/MP2MP LSPs may be used to traverse network
segments that are provided by multi-access media such as Ethernet.
In these contexts, it is also possible that the entry point to the
network segment is a branch LSR of the Receiver-Driven P2MP/MP2MP
LSP.
To avoid all replicated data are sent through the same port and
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carried on the same segment, the solution SHOULD provide a mechanism
for a branch LSR to send a single copy of the data onto a multi-
access network to reach multiple (adjacent) downstream nodes.
The Receiver-Driven P2MP/MP2MP computation mechanism SHOULD provide a
means for a Branch LSR to send a single copy of the data onto an
Ethernet LAN interface to reach multiple adjacent downstream nodes.
This requires that the same label be negotiated with all downstream
LSRs for the P2MP/MP2MP LSP.
When there are several candidate upstream LSRs on a LAN interface,
the RD P2MP TE mechanism SHOULD provide a means for all downstream
LSRs of a given P2MP LSP to select the same upstream LSR, so as to
avoid traffic replication. In addition, the RD P2MP TE mechanism
SHOULD allow for an efficient balancing of a set of P2MP LSPs among a
set of candidate upstream LSRs on a LAN interface.
4.5. P2MP/MP2MP MPLS Label
A solution for the dynamic establishment and maintenance of Receiver-
Driven P2MP LSPs MUST allow the continued use of existing techniques
to establish P2P and legacy P2MP LSPs (TE and otherwise) within the
same network, and MUST allow the coexistence of Receiver-Driven P2MP/
MP2MP LSPSs with P2P and legacy P2MP LSPs within the same network.
A solution for the dynamic establishment and maintenance of Receiver-
Driven P2MP LSPs MUST be specified in such a way that it allows
legacy P2MP and P2P TE LSPs to be signaled on the same interface.
4.6. Advertisement of Leaf Driven mRSVP-TE Capability
To facilitate the computation of Receiver-Driven P2MP trees using TE
constraints within a network whose LSRs do not all support the same
capability level with respect to Receiver-Driven P2MP RSVP-TE
signaling and data forwarding, the capability of an LSR to support
the RSVP-TE signaling and forwarding for Receiver-Driven P2MP LSPs
MUST be advertised to its neighbor LSRs.
4.7. Scalability
Scalability is a key requirement in mRSVP-TE systems. Solutions MUST
be designed to scale well as a function of the number of any of the
following:
o the number of receivers
o the number of sources
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o the number of egress LSRs
o the number of branch LSRs
o the number of branches
Furthermore, scalability of control plane operation (setup,
maintenance, modification, and teardown) MUST be considered.
Key considerations MUST include:
o The amount of refresh processing associated with maintaining a
P2MP/MP2MP TE LSP.
o The amount of protocol state that must be maintained by ingress
and transit LSRs along a P2MP/MP2MP tree.
o The number of protocol messages required to set up or tear down a
P2MP/MP2MP LSP as a function of the number of egress LSRs.
o The number of protocol messages required to repair a P2MP/MP2MP
LSP after failure or to perform make-before-break.
o The amount of protocol information transmitted to manage a P2MP/
MP2MP TE LSP (i.e., the message size).
o The amount of additional data distributed in potential routing
extensions.
o The amount of additional control plane processing required in the
network to detect whether an add/delete of a new branch is
required, and in particular, the amount of processing in steady
state when no add/delete is requested.
o The amount of control plane processing required by the ingress,
transit, and egress LSRs to add/delete a branch LSP to/from an
existing P2MP LSP.
It is expected that the applicability of each solution will be
evaluated with regards to the aforementioned scalability criteria.
In order to accommodate a growing number of leaves, it is RECOMMENDED
that the amount of a P2MP LSP/MP2MP state on a LSR, for one
particular LSP, depends only on the number of adjacent LSRs on the
LSP.
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4.8. Variation of LSP Parameters
Certain parameters (such as priority and bandwidth) are associated
with an LSP. The parameters are installed by the signaling exchanges
associated with the establishment and the maintenance of the P2MP/
MP2MP LSP.
Any solution MUST NOT allow for variance of these parameters within a
single P2MP/MP2MP LSP. That is:
o Downstream or upstream LSRs MUST NOT alter the attributes set and
signaled by a first leaf router of a P2MP/MP2MP tree structure.
o A consistent QoS policy SHOULD be enforced from the root to all
leaves of a single P2MP/MP2MP LSP.
o Some leaves of a given tree may yield the enforcement of a
different QoS policy, depending on the various access capabilities
of the receivers. Still, content will be delivered to these
receivers by using the same (core) P2MP/MP2MP tree structure.
o Changing the parameters for the whole tree MAY be supported, but
the change MUST apply to the whole tree from ingress LSR to all
egress LSRs.
5. In-Band Signalling
TBD.
6. Backwards Compatibility
Any P2MP/MP2MP TE LSP solution SHOULD offer as much backward
compatibility as possible. Also, RD P2MP TE LSPs MUST be able to
coexist with IP unicast and IP multicast networks.
7. Acknowledgements
We would like to thank authors of [RFC4461] and the authors of
[RFC6348] from which some text of this document has been inspired.
8. IANA Considerations
This memo includes no request to IANA.
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9. Security Considerations
This document does not define any protocol extensions and does not,
therefore, make any changes to any security models. It is a
requirement that any RD P2MP/MP2MP solution developed to meet some or
all of the requirements expressed in this document MUST include
mechanisms to enable the secure establishment and management. of
P2MP/MP2MP RSVP-TE LSPs. This includes, but is not limited to:
o A receiver MUST be authenticated before it is allowed to trigger
the establishment of an additional leaf of a RD P2MP LSP tree
structure, in addition to hop-by-hop security issues identified in
RFC 3209 and RFC 4206.
o mechanisms that provide some guarantees about the identity of an
ingress LSR of a P2MP/MP2MP LSP;
o mechanisms to ensure that communicating signaling entities can
verify each other's identities;
o mechanisms to ensure that control plane messages are protected
against spoofing and tampering;
o mechanisms to ensure that unauthorized leaves or branches are not
added to the P2MP/MP2MP LSP; and mechanisms to protect signaling
messages from snooping.
o Note that RD P2MP/MP2MP signaling mechanisms built on P2P RSVP-TE
signaling and RSVP-TE P2MP signalling are likely to inherit all
the security techniques and problems associated with RSVP-TE.
These problems may be exacerbated in P2MP/MP2MP situations where
security relationships may need to be maintained between an
ingress LSR and multiple egress LSRs. Such issues are similar to
security issues for IP multicast.
10. References
10.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[2] Awduche, D., Malcolm, J., Agogbua, J., O'Dell, M., and J.
McManus, "Requirements for Traffic Engineering Over MPLS",
RFC 2702, September 1999.
[3] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol Label
Jacquenet & Zhao Expires September 13, 2012 [Page 15]
Internet-Draft RD mRSVP TE Requirements March 2012
Switching Architecture", RFC 3031, January 2001.
[4] 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.
[5] Yasukawa, S., "Signaling Requirements for Point-to-Multipoint
Traffic-Engineered MPLS Label Switched Paths (LSPs)", RFC 4461,
April 2006.
[6] 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.
[7] Farrel, A., Papadimitriou, D., Vasseur, J., and A. Ayyangar,
"Encoding of Attributes for Multiprotocol Label Switching
(MPLS) Label Switched Path (LSP) Establishment Using Resource
ReserVation Protocol-Traffic Engineering (RSVP-TE)", RFC 4420,
February 2006.
[8] Kompella, K. and Y. Rekhter, "Label Switched Paths (LSP)
Hierarchy with Generalized Multi-Protocol Label Switching
(GMPLS) Traffic Engineering (TE)", RFC 4206, October 2005.
[9] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. Jamin,
"Resource ReSerVation Protocol (RSVP) -- Version 1 Functional
Specification", RFC 2205, September 1997.
[10] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute Extensions to
RSVP-TE for LSP Tunnels", RFC 4090, May 2005.
[11] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS)
Signaling Functional Description", RFC 3471, January 2003.
[12] Aggarwal, R. and J. Roux, "MPLS Upstream Label Assignment for
RSVP-TE", draft-ietf-mpls-rsvp-upstream-05 (work in progress),
March 2010.
[13] Roux, J. and T. Morin, "Requirements for Point-To-Multipoint
Extensions to the Label Distribution Protocol",
draft-ietf-mpls-mp-ldp-reqs-08 (work in progress), May 2011.
[14] Aggarwal, R. and E. Rosen, "Multicast in MPLS/BGP IP VPNs",
draft-ietf-l3vpn-2547bis-mcast-10 (work in progress),
January 2010.
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Internet-Draft RD mRSVP TE Requirements March 2012
10.2. Informative References
[15] Andersson, L. and G. Swallow, "The Multiprotocol Label
Switching (MPLS) Working Group decision on MPLS signaling
protocols", RFC 3468, February 2003.
[16] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS)
Signaling Resource ReserVation Protocol-Traffic Engineering
(RSVP-TE) Extensions", RFC 3473, January 2003.
[17] Le Faucheur, F. and W. Lai, "Requirements for Support of
Differentiated Services-aware MPLS Traffic Engineering",
RFC 3564, July 2003.
[18] Berger, L., Takacs, A., Caviglia, D., Fedyk, D., and J. Meuric,
"GMPLS Asymmetric Bandwidth Bidirectional Label Switched Paths
(LSPs)", RFC 5467, March 2009.
Authors' Addresses
Christian Jacquenet
France Telecom Orange
4 rue du Clos Courtel
35512 Cesson Sevigne
France
Phone: +33 2 99 12 43 82
Email: christian.jacquenet@orange-ftgroup.com
Quintin Zhao
Huawei Technology
125 Nagog Park
Acton, MA 01919
US
Phone:
Email: qzhao@huawei.com
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