draft-ietf-mpls-mldp-in-band-signaling-08.txt   rfc6826.txt 
Network Working Group IJ. Wijnands, Ed. Internet Engineering Task Force (IETF) IJ. Wijnands, Ed.
Internet-Draft T. Eckert Request for Comments: 6826 T. Eckert
Intended status: Standards Track Cisco Systems, Inc. Category: Standards Track Cisco Systems, Inc.
Expires: June 2, 2013 N. Leymann ISSN: 2070-1721 N. Leymann
Deutsche Telekom Deutsche Telekom
M. Napierala M. Napierala
AT&T Labs AT&T Labs
November 29, 2012 January 2013
Multipoint LDP in-band signaling for Point-to-Multipoint and Multipoint- Multipoint LDP In-Band Signaling for
to-Multipoint Label Switched Paths Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths
draft-ietf-mpls-mldp-in-band-signaling-08
Abstract Abstract
Consider an IP multicast tree, constructed by Protocol Independent Consider an IP multicast tree, constructed by Protocol Independent
Multicast (PIM), needs to pass through an MPLS domain in which Multicast (PIM), that needs to pass through an MPLS domain in which
Multipoint LDP (mLDP) Point-to-Multipoint and/or Multipoint-to- Multipoint LDP (mLDP) point-to-multipoint and/or multipoint-to-
Multipoint Labels Switched Paths (LSPs) can be created. The part of multipoint Labels Switched Paths (LSPs) can be created. The part of
the IP multicast tree that traverses the MPLS domain can be the IP multicast tree that traverses the MPLS domain can be
instantiated as a multipoint LSP. When a PIM Join message is instantiated as a multipoint LSP. When a PIM Join message is
received at the border of the MPLS domain, information from that received at the border of the MPLS domain, information from that
message is encoded into mLDP messages. When the mLDP messages reach message is encoded into mLDP messages. When the mLDP messages reach
the border of the next IP domain, the encoded information is used to the border of the next IP domain, the encoded information is used to
generate PIM messages that can be sent through the IP domain. The generate PIM messages that can be sent through the IP domain. The
result is an IP multicast tree consisting of a set of IP multicast result is an IP multicast tree consisting of a set of IP multicast
sub-trees that are spliced together with a multipoint LSP. This sub-trees that are spliced together with a multipoint LSP. This
document describes procedures how IP multicast trees are spliced document describes procedures regarding how IP multicast trees are
together with multipoint LSPs. spliced together with multipoint LSPs.
Status of this Memo
This Internet-Draft is submitted in full conformance with the Status of This Memo
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering This is an Internet Standards Track document.
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
This Internet-Draft will expire on June 2, 2013. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6826.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Conventions used in this document . . . . . . . . . . . . 3 1.1. Conventions Used in This Document . . . . . . . . . . . . 3
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
2. In-band signaling for MP LSPs . . . . . . . . . . . . . . . . 4 2. In-Band Signaling for MP LSPs . . . . . . . . . . . . . . . . 4
2.1. Transiting Unidirectional IP multicast Shared Trees . . . 6 2.1. Transiting Unidirectional IP Multicast Shared Trees . . . 6
2.2. Transiting IP multicast source trees . . . . . . . . . . . 6 2.2. Transiting IP Multicast Source Trees . . . . . . . . . . . 6
2.3. Transiting IP multicast bidirectional trees . . . . . . . 7 2.3. Transiting IP Multicast Bidirectional Trees . . . . . . . 7
3. LSP opaque encodings . . . . . . . . . . . . . . . . . . . . . 7 3. LSP Opaque Encodings . . . . . . . . . . . . . . . . . . . . . 8
3.1. Transit IPv4 Source TLV . . . . . . . . . . . . . . . . . 7 3.1. Transit IPv4 Source TLV . . . . . . . . . . . . . . . . . 8
3.2. Transit IPv6 Source TLV . . . . . . . . . . . . . . . . . 8 3.2. Transit IPv6 Source TLV . . . . . . . . . . . . . . . . . 8
3.3. Transit IPv4 bidir TLV . . . . . . . . . . . . . . . . . . 9 3.3. Transit IPv4 Bidir TLV . . . . . . . . . . . . . . . . . . 9
3.4. Transit IPv6 bidir TLV . . . . . . . . . . . . . . . . . . 9 3.4. Transit IPv6 Bidir TLV . . . . . . . . . . . . . . . . . . 9
4. Security Considerations . . . . . . . . . . . . . . . . . . . 10 4. Security Considerations . . . . . . . . . . . . . . . . . . . 10
5. IANA considerations . . . . . . . . . . . . . . . . . . . . . 10 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 10
7. Contributing authors . . . . . . . . . . . . . . . . . . . . . 11 6.1. Normative References . . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6.2. Informative References . . . . . . . . . . . . . . . . . . 10
8.1. Normative References . . . . . . . . . . . . . . . . . . . 11 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11
8.2. Informative References . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
The mLDP (Multipoint LDP) [RFC6388] specification describes The mLDP (Multipoint LDP) [RFC6388] specification describes
mechanisms for creating point-to-multipoint (P2MP) and multipoint-to- mechanisms for creating point-to-multipoint (P2MP) and multipoint-to-
multipoint (MP2MP) LSPs (Label Switched Paths). These LSPs are multipoint (MP2MP) LSPs (Label Switched Paths). These LSPs are
typically used for transporting end-user multicast packets. However, typically used for transporting end-user multicast packets. However,
the mLDP specification does not provide any rules for associating the mLDP specification does not provide any rules for associating
particular end-user multicast packets with any particular LSP. Other particular end-user multicast packets with any particular LSP. Other
documents, like [RFC6513], describe applications in which out-of-band documents, like [RFC6513], describe applications in which out-of-band
signaling protocols, such as PIM and BGP, are used to establish the signaling protocols, such as PIM and BGP, are used to establish the
mapping between an LSP and the multicast packets that need to be mapping between an LSP and the multicast packets that need to be
forwarded over the LSP. forwarded over the LSP.
This document describes an application in which the information This document describes an application in which the information
needed to establish the mapping between an LSP and the set of needed to establish the mapping between an LSP and the set of
multicast packets to be forwarded over it is carried in the "opaque multicast packets to be forwarded over it is carried in the "opaque
value" field of an mLDP FEC (Forwarding Equivalence Class) element. value" field of an mLDP FEC (Forwarding Equivalence Class) element.
When an IP multicast tree (either a source-specific tree or a When an IP multicast tree (either a source-specific tree or a
bidirectional tree) enters the MPLS network the (S,G) or (*,G) bidirectional tree) enters the MPLS network, the (S,G) or (*,G)
information from the IP multicast control plane state is carried in information from the IP multicast control-plane state is carried in
the opaque value field of the mLDP FEC message. As the tree leaves the opaque value field of the mLDP FEC message. As the tree leaves
the MPLS network, this information is extracted from the FEC element the MPLS network, this information is extracted from the FEC Element
and used to build the IP multicast control plane. PIM messages can and used to build the IP multicast control plane. PIM messages can
be sent outside the MPLS domain. Note that although the PIM control be sent outside the MPLS domain. Note that although the PIM control
messages are sent periodically, the mLDP messages are not. messages are sent periodically, the mLDP messages are not.
Each IP multicast tree is mapped one-to-one to a P2MP or MP2MP LSP in Each IP multicast tree is mapped one-to-one to a P2MP or MP2MP LSP in
the MPLS network. A network operator should expect to see as many the MPLS network. A network operator should expect to see as many
LSPs in the MPLS network as there are IP multicast trees. A network LSPs in the MPLS network as there are IP multicast trees. A network
operator should be aware how IP multicast state is created in the operator should be aware how IP multicast state is created in the
network to ensure it does not exceed the scalability numbers of the network to ensure that it does not exceed the scalability numbers of
protocol, either PIM or mLDP. the protocol, either PIM or mLDP.
1.1. Conventions used in this document 1.1. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
1.2. Terminology 1.2. Terminology
IP multicast tree : An IP multicast distribution tree identified by ASM: PIM Any Source Multicast
a IP multicast Group address and optionally a Source IP address,
also referred to as (S,G) and (*,G).
RP: The PIM Rendezvous Point. Egress LSR: One of potentially many destinations of an LSP; also
referred to as leaf node in the case of P2MP and MP2MP LSPs.
SSM: PIM Source Specific Multicast. In-band signaling: Using the opaque value of an mLDP FEC Element to
carry the (S,G) or (*,G) identifying a particular IP multicast
tree.
ASM: PIM Any Source Multicast. Ingress LSR: Source of the P2MP LSP; also referred to as a root
node.
mLDP : Multipoint LDP. IP multicast tree: An IP multicast distribution tree identified by
an IP multicast Group address and, optionally, by a Source IP
address, also referred to as (S,G) and (*,G).
Transit LSP : A P2MP or MP2MP LSP whose FEC element contains the LSR: Label Switching Router
(S,G) or (*,G) identifying a particular IP multicast distribution
tree.
In-band signaling : Using the opaque value of a mLDP FEC element to LSP: Labels Switched Path
carry the (S,G) or (*,G) identifying a particular IP multicast
tree.
P2MP LSP: An LSP that has one Ingress LSR and one or more Egress mLDP: Multipoint LDP
LSRs.
MP2MP LSP: An LSP that connects a set of leaf nodes that may each MP2MP LSP: An LSP that connects a set of leaf nodes that may each
independently act as ingress or egress. independently act as ingress or egress.
MP LSP: A multipoint LSP, either a P2MP or an MP2MP LSP. MP LSP: A multipoint LSP, either a P2MP or an MP2MP LSP.
Ingress LSR: Source of the P2MP LSP, also referred to as root node. P2MP LSP: An LSP that has one Ingress Label Switching Router (LSR)
and one or more Egress LSRs.
Egress LSR: One of potentially many destinations of an LSP, also RP: PIM Rendezvous Point
referred to as leaf node in the case of P2MP and MP2MP LSPs.
SSM: PIM Source-Specific Multicast
Transit LSP: A P2MP or MP2MP LSP whose FEC Element contains the
(S,G) or (*,G) identifying a particular IP multicast distribution
tree.
Transit LSR: An LSR that has one or more directly connected Transit LSR: An LSR that has one or more directly connected
downstream LSRs. downstream LSRs.
2. In-band signaling for MP LSPs 2. In-Band Signaling for MP LSPs
Consider the following topology; Consider the following topology:
|--- IPM ---|--- MPLS --|--- IPM ---|
S/RP -- (A) - (U) - (C) - (D) -- (B) -- R |--- IPM ---|--- MPLS --|--- IPM ---|
Figure 1. S/RP -- (A) - (U) - (C) - (D) -- (B) -- R
Nodes A and B are IP Multicast capable routers and respectively Figure 1
connect to a Source/RP and a Receiver. Nodes U, C and D are MPLS
Nodes A and B are IP-multicast-capable routers and connect to a
Source/RP and a Receiver, respectively. Nodes U, C, and D are MPLS
Label Switched Routers (LSRs). Label Switched Routers (LSRs).
Label Switched Router D is attached to a network that is capable of LSR D is attached to a network that is capable of MPLS multicast and
MPLS multicast and IP multicast (see figure 1), and D is required to IP multicast (see figure 1), and D is required to create a IP
create a IP multicast tree due to a certain IP multicast event, like multicast tree due to a certain IP multicast event, like a PIM Join,
a PIM Join, MSDP Source Announcement (SA) [RFC3618], BGP Source MSDP Source Announcement (SA) [RFC3618], BGP Source Active auto-
Active auto-discovery route [I-D.rekhter-pim-sm-over-mldp] or discovery route [SM-MLDP], or Rendezvous Point (RP) discovery.
Rendezvous Point (RP) discovery. Suppose that D can determine that Suppose that D can determine that the IP multicast tree needs to
the IP multicast tree needs to travel through the MPLS network until travel through the MPLS network until it reaches LSR U. For
it reaches LSR U. For instance, when D looks up the route to the instance, when D looks up the route to the Source or RP [RFC4601] of
Source or RP [RFC4601] of the IP multicast tree, it may discover that the IP multicast tree, it may discover that the route is a BGP route
the route is a BGP route with U as the BGP next hop. Then D may with U as the BGP next hop. Then D may choose to set up a P2MP or an
chose to set up a P2MP or MP2MP LSP, with U as root, and to make that MP2MP LSP, with U as root, and to make that LSP become part of the IP
LSP become part of the IP multicast distribution tree. Note that multicast distribution tree. Note that other methods are possible to
other methods are possible to determine that an IP multicast tree is determine that an IP multicast tree is to be transported across an
to be transported across an MPLS network using P2MP or MP2MP LSPs, MPLS network using P2MP or MP2MP LSPs. However, these methods are
these methods are outside the scope of this document. outside the scope of this document.
In order to establish a multicast tree via a P2MP or MP2MP LSP using In order to establish a multicast tree via a P2MP or MP2MP LSP using
"in-band signaling", LSR D encodes a P2MP or MP2MP FEC Element, with "in-band signaling", LSR D encodes a P2MP or MP2MP FEC Element, with
the IP address of LSR U as the "Root Node Address", and with the the IP address of LSR U as the "Root Node Address" and with the
source and the group encoded into the "opaque value" ([RFC6388], source and the group encoded into the "opaque value" ([RFC6388],
section 2.2 and 3.2). Several different opaque value types are Sections 2.2 and 3.2). Several different opaque value types are
defined in this document; LSR D MUST NOT use a particular opaque defined in this document. LSR D MUST NOT use a particular opaque
value type unless it knows (through provisioning, or through some value type unless it knows (through provisioning or through some
other means outside the scope of this document) that LSR U supports other means outside the scope of this document) that LSR U supports
the root node procedures for that opaque value type. the root node procedures for that opaque value type.
The particular type of FEC Element and opaque value used depends on The particular type of FEC Element and opaque value used depends on
the IP address family being used, and on whether the multicast tree the IP address family being used, and on whether the multicast tree
being established is a source specific or a bidirectional multicast being established is a source-specific or a bidirectional multicast
tree. tree.
When an LSR receives a label mapping or withdraw whose FEC Element When an LSR receives a label mapping or withdraw whose FEC Element
contains one of the opaque value types defined in this document, and contains one of the opaque value types defined in this document, and
that LSR is not the one identified by the "Root Node Address" field that LSR is not the one identified by the "Root Node Address" field
of that FEC element, the LSR follows the procedures of RFC 6388. of that FEC Element, the LSR follows the procedures provided in RFC
6388.
When an LSR receives a label mapping or withdraw whose FEC Element When an LSR receives a label mapping or withdraw whose FEC Element
contains one of the opaque value types defined in this document, and contains one of the opaque value types defined in this document, and
that LSR is the one identified by the "Root Node Address" field of that LSR is the one identified by the Root Node Address field of that
that FEC element, then the following procedure is executed. The FEC Element, then the following procedure is executed. The multicast
multicast source and group are extracted and passed to the multicast source and group are extracted and passed to the multicast code. If
code. If a label mapping is being processed, the multicast code will a label mapping is being processed, the multicast code will add the
add the downstream LDP neighbor to the olist of the corresponding downstream LDP neighbor to the olist of the corresponding (S,G) or
(S,G) or (*,G) state, creating such state if it does not already (*,G) state, creating such state if it does not already exist. If a
exist. If a label withdraw is being processed, the multicast code label withdraw is being processed, the multicast code will remove the
will remove the downstream LDP neighbor from the olist of the downstream LDP neighbor from the olist of the corresponding (S,G) or
corresponding (S,G) or (*,G) state. From this point on normal PIM (*,G) state. From this point on, normal PIM processing will occur.
processing will occur.
Note that if the LSR identified by the "Root Node Address" field does Note that if the LSR identified by the Root Node Address field does
not recognize the opaque value type, the MP LSP will be established, not recognize the opaque value type, the MP LSP will be established,
but the root node will not send any multicast data packets on it. but the root node will not send any multicast data packets on it.
Source or RP addresses that are reachable in a VPN context are Source or RP addresses that are reachable in a VPN context are
outside the scope of this document. outside the scope of this document.
Multicast groups that operate in PIM Dense-Mode are outside the scope Multicast groups that operate in PIM Dense-Mode are outside the scope
of this document. of this document.
2.1. Transiting Unidirectional IP multicast Shared Trees 2.1. Transiting Unidirectional IP Multicast Shared Trees
Nothing prevents PIM shared trees, used by PIM-SM in the ASM service Nothing prevents PIM shared trees, used by PIM-SM in the ASM service
model, from being transported across a MPLS core. However, it is not model, from being transported across an MPLS core. However, it is
possible to prune individual sources from the shared tree without the not possible to prune individual sources from the shared tree without
use of an additional out-of-band signaling protocol, like PIM or BGP the use of an additional out-of-band signaling protocol, like PIM or
[I-D.rekhter-pim-sm-over-mldp]. For that reason transiting Shared BGP [SM-MLDP]. For this reason, transiting shared trees across a
Trees across a Transit LSP is outside the scope of this document. transit LSP is outside the scope of this document.
2.2. Transiting IP multicast source trees 2.2. Transiting IP Multicast Source Trees
IP multicast source trees can either be created via PIM operating in IP multicast source trees can be created via PIM operating in either
SSM mode [RFC4607] or ASM mode [RFC4601]. When PIM-SM is used in ASM SSM mode [RFC4607] or ASM mode [RFC4601]. When PIM-SM is used in ASM
mode, the usual means of discovering active sources is to join a mode, the usual means of discovering active sources is to join a
sparse mode shared tree. However, this document does not provide any sparse-mode shared tree. However, this document does not provide any
method of establishing a sparse mode shared tree across an MPLS method of establishing a sparse-mode shared tree across an MPLS
network. To apply the technique of this document to PIM-SM in ASM network. To apply the technique of this document to PIM-SM in ASM
mode, there must be some other means of discovering the active mode, there must be some other means of discovering the active
sources. One possible means is the use of MSDP [RFC3618]. Another sources. One possible means is the use of MSDP [RFC3618]. Another
possible means is to use BGP Source Active auto-discovery routes, as possible means is to use BGP Source Active auto-discovery routes, as
documented in [I-D.rekhter-pim-sm-over-mldp]. However, the method of documented in [SM-MLDP]. However, the method of discovering the
discovering the active sources is outside the scope of this document, active sources is outside the scope of this document; as a result,
and as a result this document does not specify everything that is this document does not specify everything that is needed to support
needed to support the ASM service model using in-band signaling. the ASM service model using in-band signaling.
The source and group addresses are encoded into the a transit TLV as The source and group addresses are encoded into the a transit TLV as
specified in Section 3.1 and Section 3.2. specified in Sections 3.1 and 3.2.
2.3. Transiting IP multicast bidirectional trees 2.3. Transiting IP Multicast Bidirectional Trees
If a Bidirectional IP multicast trees [RFC5015] has to be transported If a bidirectional IP multicast tree [RFC5015] has to be transported
over a MPLS network using in-band signaling, as described in this over an MPLS network using in-band signaling, as described in this
document, it MUST be transported using a MP2MP LSPs. A bidirectional document, it MUST be transported using an MP2MP LSPs. A
tree does not have a specific source address; the group address, bidirectional tree does not have a specific source address; the group
subnet mask and RP are relevant for multicast forwarding. This address, subnet mask, and RP are relevant for multicast forwarding.
document does not provide procedures to discover RP to group mappings This document does not provide procedures to discover RP-to-group
dynamically across an MPLS network and assumes the RP is statically mappings dynamically across an MPLS network and assumes the RP is
defined. Support of dynamic RP mappings in combination with in-band statically defined. Support of dynamic RP mappings in combination
signaling is outside the scope of his document. with in-band signaling is outside the scope of this document.
The RP for the group is used to select the ingress LSR and root of The RP for the group is used to select the ingress LSR and the root
the LSP. The group address is encoded according to the rules of of the LSP. The group address is encoded according to the rules of
Section 3.3 or Section 3.4, depending on the IP version. The subnet Sections 3.3 or 3.4, depending on the IP version. The subnet mask
mask associated with the bidirectional group is encoded in the associated with the bidirectional group is encoded in the Transit
Transit TLV. There are two types of bidirectional states in IP TLV. There are two types of bidirectional states in IP multicast,
multicast, the group specific state and the RP state. The first type the group specific state and the RP state. The first type is
is typically created due to receiving a PIM join and has a subnet typically created when a PIM Join has been received and has a subnet
mask of 32 for IPv4 and 128 for IPv6. The latter is typically mask of 32 for IPv4 and 128 for IPv6. The RP state is typically
created via the static RP mapping and has a variable subnet mask. created via the static RP mapping and has a variable subnet mask.
The RP state is used to build a tree to the RP and used for sender The RP state is used to build a tree to the RP and is used for
only branches. Each state (group specific and RP state) will result sender-only branches. Each state (group specific and RP state) will
in a separate MP2MP LSP. The merging of the two MP2MP LSPs will be result in a separate MP2MP LSP. The merging of the two MP2MP LSPs
done by PIM on the root LSR. No special procedures are necessary for will be done by PIM on the root LSR. No special procedures are
PIM to merge the two LSPs, each LSP is effectively treated as a PIM necessary for PIM to merge the two LSPs. Each LSP is effectively
enabled interface. Please see [RFC5015] for more details. treated as a PIM-enabled interface. Please see [RFC5015] for more
details.
For transporting the packets of a sender only branch we create a For transporting the packets of a sender-only branch, we create a
MP2MP LSP. Other sender only branches will receive these packets and MP2MP LSP. Other sender-only branches will receive these packets and
will not forward them because there are no receivers. These packets will not forward them because there are no receivers. These packets
will be dropped. If that affect is undesireable some other means of will be dropped. If that effect is undesirable, some other means of
transport has to be established to forward packets to the root of the transport has to be established to forward packets to the root of the
tree, like a Multi-Point to Point LSP for example. A technique to tree, for example, a multipoint-to-point LSP for example. A
unicast packets to the root of a P2MP or MP2MP LSP is documented in technique to unicast packets to the root of a P2MP or MP2MP LSP is
[I-D.rosen-l3vpn-mvpn-mspmsi] section 3.2.2.1. documented in Section 3.2.2.1 of [MVPN-MSPMSI].
3. LSP opaque encodings 3. LSP Opaque Encodings
This section documents the different transit opaque encodings. This section documents the different transit opaque encodings.
3.1. Transit IPv4 Source TLV 3.1. Transit IPv4 Source TLV
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | Source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 3 (to be assigned by IANA). 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 | Source |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 3
Length: 8 (octet size of Source and Group fields) Length: 8 (octet size of Source and Group fields)
Source: IPv4 multicast source address, 4 octets. Source: IPv4 multicast source address, 4 octets
Group: IPv4 multicast group address, 4 octets. Group: IPv4 multicast group address, 4 octets
3.2. Transit IPv6 Source TLV 3.2. Transit IPv6 Source TLV
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 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 | Source ~ | Type | Length | Source ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ | Group ~ ~ | Group ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ | ~ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 4 (to be assigned by IANA). Type: 4
Length: 32 (octet size of Source and Group fields) Length: 32 (octet size of Source and Group fields)
Source: IPv6 multicast source address, 16 octets. Source: IPv6 multicast source address, 16 octets
Group: IPv6 multicast group address, 16 octets. Group: IPv6 multicast group address, 16 octets.
3.3. Transit IPv4 bidir TLV 3.3. Transit IPv4 Bidir TLV
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 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 | Mask Len | | Type | Length | Mask Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RP | | RP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group | | Group |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 5 (to be assigned by IANA). Type: 5
Length: 9 (octet size of Mask Len, RP and Group fields) Length: 9 (octet size of Mask Len, RP, and Group fields)
Mask Len: The number of contiguous one bits that are left justified Mask Len: The number of contiguous one bits that are left-justified
and used as a mask, 1 octet. Maximum value allowed is 32. and used as a mask, 1 octet. Maximum value allowed is 32.
RP: Rendezvous Point (RP) IPv4 address used for encoded Group, 4 RP: Rendezvous Point (RP) IPv4 address used for the encoded Group, 4
octets. octets.
Group: IPv4 multicast group address, 4 octets. Group: IPv4 multicast group address, 4 octets.
3.4. Transit IPv6 bidir TLV 3.4. Transit IPv6 Bidir TLV
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 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 | Mask Len | | Type | Length | Mask Len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| RP ~ | RP ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ | ~ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group ~ | Group ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ | ~ |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: 6 (to be assigned by IANA). Type: 6
Length: 33 (octet size of Mask Len, RP and Group fields) Length: 33 (octet size of Mask Len, RP and Group fields)
Mask Len: The number of contiguous one bits that are left justified Mask Len: The number of contiguous one bits that are left-justified
and used as a mask, 1 octet. Maximum value allowed is 128. and used as a mask, 1 octet. Maximum value allowed is 128.
RP: Rendezvous Point (RP) IPv6 address used for encoded group, 16 RP: Rendezvous Point (RP) IPv6 address used for encoded group, 16
octets. octets.
Group: IPv6 multicast group address, 16 octets. Group: IPv6 multicast group address, 16 octets.
4. Security Considerations 4. Security Considerations
The same security considerations apply as for the base LDP The same security considerations apply as for the base LDP
specification, as described in [RFC5036]. specification, as described in [RFC5036].
5. IANA considerations 5. IANA Considerations
This document requires allocation from the 'LDP MP Opaque Value IANA has allocated the following values from the "LDP MP Opaque Value
Element basic type' name space managed by IANA. The values requested Element basic type" registry: are:
are:
Transit IPv4 Source TLV type - 3 Transit IPv4 Source TLV type - 3
Transit IPv6 Source TLV type - 4 Transit IPv6 Source TLV type - 4
Transit IPv4 Bidir TLV type - 5 Transit IPv4 Bidir TLV type - 5
Transit IPv6 Bidir TLV type - 6 Transit IPv6 Bidir TLV type - 6
6. Acknowledgments 6. References
Thanks to Eric Rosen for his valuable comments on this document.
Also thanks to Yakov Rekhter, Adrian Farrel, Uwe Joorde, Loa
Andersson and Arkadiy Gulko for providing comments on this document.
7. Contributing authors
Below is a list of the contributing authors in alphabetical order:
Toerless Eckert
Cisco Systems, Inc.
170 Tasman Drive
San Jose, CA, 95134
USA
E-mail: eckert@cisco.com
Nicolai Leymann
Deutsche Telekom
Winterfeldtstrasse 21
Berlin, 10781
Germany
E-mail: n.leymann@telekom.de
Maria Napierala
AT&T Labs
200 Laurel Avenue
Middletown, NJ 07748
USA
E-mail: mnapierala@att.com
IJsbrand Wijnands
Cisco Systems, Inc.
De kleetlaan 6a
1831 Diegem
Belgium
E-mail: ice@cisco.com
8. References
8.1. Normative References 6.1. Normative References
[RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP [RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed.,
Specification", RFC 5036, October 2007. "LDP Specification", RFC 5036, October 2007.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC6388] Wijnands, IJ., Minei, I., Kompella, K., and B. Thomas, [RFC6388] Wijnands, IJ., Ed., Minei, I., Ed., Kompella, K., and B.
"Label Distribution Protocol Extensions for Point-to- Thomas, "Label Distribution Protocol Extensions for Point-
Multipoint and Multipoint-to-Multipoint Label Switched to-Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, November 2011. Paths", RFC 6388, November 2011.
8.2. Informative References 6.2. Informative References
[RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas, [RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas,
"Protocol Independent Multicast - Sparse Mode (PIM-SM): "Protocol Independent Multicast - Sparse Mode (PIM-SM):
Protocol Specification (Revised)", RFC 4601, August 2006. Protocol Specification (Revised)", RFC 4601, August 2006.
[RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for [RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for
IP", RFC 4607, August 2006. IP", RFC 4607, August 2006.
[RFC5015] Handley, M., Kouvelas, I., Speakman, T., and L. Vicisano, [RFC5015] Handley, M., Kouvelas, I., Speakman, T., and L. Vicisano,
"Bidirectional Protocol Independent Multicast (BIDIR- "Bidirectional Protocol Independent Multicast (BIDIR-
PIM)", RFC 5015, October 2007. PIM)", RFC 5015, October 2007.
[RFC3618] Fenner, B. and D. Meyer, "Multicast Source Discovery [RFC3618] Fenner, B., Ed., and D. Meyer, Ed., "Multicast Source
Protocol (MSDP)", RFC 3618, October 2003. Discovery Protocol (MSDP)", RFC 3618, October 2003.
[RFC6513] Rosen, E. and R. Aggarwal, "Multicast in MPLS/BGP IP [RFC6513] Rosen, E., Ed., and R. Aggarwal, Ed., "Multicast in
VPNs", RFC 6513, February 2012. MPLS/BGP IP VPNs", RFC 6513, February 2012.
[I-D.rekhter-pim-sm-over-mldp] [SM-MLDP] Rekhter, Y., Aggarwal, R., and N. Leymann, "Carrying PIM-
Rekhter, Y. and R. Aggarwal, "Carrying PIM-SM in ASM mode SM in ASM mode Trees over P2MP mLDP LSPs", Work in
Trees over P2MP mLDP LSPs", Progress, August 2011.
draft-rekhter-pim-sm-over-mldp-04 (work in progress),
August 2011.
[I-D.rosen-l3vpn-mvpn-mspmsi] [MVPN-MSPMSI]
Cai, Y., Rosen, E., Wijnands, I., Napierala, M., and A. Cai, Y., Rosen, E., Ed., Napierala, M., and A. Boers,
Boers, "MVPN: Optimized use of PIM via MS-PMSIs", MVPN: Optimized use of PIM via MS-PMSIs", February 2012.
draft-rosen-l3vpn-mvpn-mspmsi-10 (work in progress),
February 2012. 7. Acknowledgments
Thanks to Eric Rosen for his valuable comments on this document.
Also thanks to Yakov Rekhter, Adrian Farrel, Uwe Joorde, Loa
Andersson and Arkadiy Gulko for providing comments on this document.
Authors' Addresses Authors' Addresses
IJsbrand Wijnands (editor) IJsbrand Wijnands (editor)
Cisco Systems, Inc. Cisco Systems, Inc.
De kleetlaan 6a De kleetlaan 6a
Diegem 1831 Diegem 1831
Belgium Belgium
Email: ice@cisco.com EMail: ice@cisco.com
Toerless Eckert Toerless Eckert
Cisco Systems, Inc. Cisco Systems, Inc.
170 Tasman Drive 170 Tasman Drive
San Jose CA, 95134 San Jose CA, 95134
USA USA
Email: eckert@cisco.com EMail: eckert@cisco.com
Nicolai Leymann Nicolai Leymann
Deutsche Telekom Deutsche Telekom
Winterfeldtstrasse 21 Winterfeldtstrasse 21
Berlin 10781 Berlin 10781
Germany Germany
Email: n.leymann@telekom.de EMail: n.leymann@telekom.de
Maria Napierala Maria Napierala
AT&T Labs AT&T Labs
200 Laurel Avenue 200 Laurel Avenue
Middletown NJ 07748 Middletown NJ 07748
USA USA
Email: mnapierala@att.com EMail: mnapierala@att.com
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