draft-ietf-mpls-mldp-hsmp-06.txt   rfc7140.txt 
Network Working Group L. Jin Internet Engineering Task Force (IETF) L. Jin
Internet-Draft Request for Comments: 7140
Intended status: Standards Track F. Jounay Category: Standards Track F. Jounay
Expires: July 2, 2014 France Telecom ISSN: 2070-1721 Orange CH
I. Wijnands IJ. Wijnands
Cisco Systems, Inc Cisco Systems, Inc
N. Leymann N. Leymann
Deutsche Telekom AG Deutsche Telekom AG
December 29, 2013 March 2014
LDP Extensions for Hub & Spoke Multipoint Label Switched Path LDP Extensions for Hub and Spoke Multipoint Label Switched Path
draft-ietf-mpls-mldp-hsmp-06.txt
Abstract Abstract
This draft introduces a hub & spoke multipoint (HSMP) Label Switched This document introduces a hub and spoke multipoint (HSMP) Label
Path (LSP), which allows traffic both from root to leaf through Switched Path (LSP), which allows traffic from root to leaf through
point-to-multipoint (P2MP) LSP and also leaf to root along the point-to-multipoint (P2MP) LSPs and also leaf to root along the
reverse path. That means traffic entering the HSMP LSP from reverse path. That means traffic entering the HSMP LSP from the
application/customer at the root node travels downstream to each leaf application/customer at the root node travels downstream to each leaf
node, exactly as if it is travelling downstream along a P2MP LSP to node, exactly as if it were traveling downstream along a P2MP LSP to
each leaf node. Upstream traffic entering the HSMP LSP at any leaf each leaf node. Upstream traffic entering the HSMP LSP at any leaf
node travels upstream along the tree to the root, as if it is unicast node travels upstream along the tree to the root, as if it were
to the root. Direct communication among the leaf nodes is not unicast to the root. Direct communication among the leaf nodes is
allowed. not allowed.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC2119 [RFC2119].
Status of this Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering This document is a product of the Internet Engineering Task Force
Task Force (IETF). Note that other groups may also distribute (IETF). It represents the consensus of the IETF community. It has
working documents as Internet-Drafts. The list of current Internet- received public review and has been approved for publication by the
Drafts is at http://datatracker.ietf.org/drafts/current/. Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 5741.
Internet-Drafts are draft documents valid for a maximum of six months Information about the current status of this document, any errata,
and may be updated, replaced, or obsoleted by other documents at any and how to provide feedback on it may be obtained at
time. It is inappropriate to use Internet-Drafts as reference http://www.rfc-editor.org/info/rfc7140.
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This Internet-Draft will expire on July 2, 2014.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2014 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 . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Setting up HSMP LSP with LDP . . . . . . . . . . . . . . . . . 5 3. Setting Up HSMP LSP with LDP . . . . . . . . . . . . . . . . 4
3.1. Support for HSMP LSP Setup with LDP . . . . . . . . . . . 5 3.1. Support for HSMP LSP Setup with LDP . . . . . . . . . . . 4
3.2. HSMP FEC Elements . . . . . . . . . . . . . . . . . . . . 6 3.2. HSMP FEC Elements . . . . . . . . . . . . . . . . . . . . 5
3.3. Using the HSMP FEC Elements . . . . . . . . . . . . . . . 6 3.3. Using the HSMP FEC Elements . . . . . . . . . . . . . . . 5
3.4. HSMP LSP Label Map . . . . . . . . . . . . . . . . . . . . 7 3.4. HSMP LSP Label Map . . . . . . . . . . . . . . . . . . . 6
3.4.1. HSMP LSP Leaf Node Operation . . . . . . . . . . . . . 8 3.4.1. HSMP LSP Leaf Node Operation . . . . . . . . . . . . 7
3.4.2. HSMP LSP Transit Node Operation . . . . . . . . . . . 8 3.4.2. HSMP LSP Transit Node Operation . . . . . . . . . . . 7
3.4.3. HSMP LSP Root Node Operation . . . . . . . . . . . . . 9 3.4.3. HSMP LSP Root Node Operation . . . . . . . . . . . . 8
3.5. HSMP LSP Label Withdraw . . . . . . . . . . . . . . . . . 10 3.5. HSMP LSP Label Withdraw . . . . . . . . . . . . . . . . . 9
3.5.1. HSMP Leaf Operation . . . . . . . . . . . . . . . . . 10 3.5.1. HSMP Leaf Operation . . . . . . . . . . . . . . . . . 9
3.5.2. HSMP Transit Node Operation . . . . . . . . . . . . . 10 3.5.2. HSMP Transit Node Operation . . . . . . . . . . . . . 9
3.5.3. HSMP Root Node Operation . . . . . . . . . . . . . . . 10 3.5.3. HSMP Root Node Operation . . . . . . . . . . . . . . 10
3.6. HSMP LSP Upstream LSR Change . . . . . . . . . . . . . . . 11 3.6. HSMP LSP Upstream LSR Change . . . . . . . . . . . . . . 10
3.7. Determining Forwarding Interface . . . . . . . . . . . . . 11 3.7. Determining Forwarding Interface . . . . . . . . . . . . 10
4. HSMP LSP on a LAN . . . . . . . . . . . . . . . . . . . . . . 11 4. HSMP LSP on a LAN . . . . . . . . . . . . . . . . . . . . . . 11
5. Redundancy Considerations . . . . . . . . . . . . . . . . . . 12 5. Redundancy Considerations . . . . . . . . . . . . . . . . . . 11
6. Failure Detection of HSMP LSP . . . . . . . . . . . . . . . . 12 6. Failure Detection of HSMP LSP . . . . . . . . . . . . . . . . 11
7. Security Considerations . . . . . . . . . . . . . . . . . . . 13 7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
8.1. New LDP FEC Element types . . . . . . . . . . . . . . . . 13 8.1. New LDP FEC Element Types . . . . . . . . . . . . . . . . 12
8.2. HSMP LSP capability TLV . . . . . . . . . . . . . . . . . 13 8.2. HSMP LSP Capability TLV . . . . . . . . . . . . . . . . . 13
8.3. New sub-TLVs for the Target Stack TLV . . . . . . . . . . 14 8.3. New Sub-TLVs for the Target Stack TLV . . . . . . . . . . 13
9. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 14 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
10.1. Normative references . . . . . . . . . . . . . . . . . . . 14 10.1. Normative References . . . . . . . . . . . . . . . . . . 14
10.2. Informative References . . . . . . . . . . . . . . . . . . 15 10.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
The point-to-multipoint (P2MP) Label Switched Path (LSP) defined in The point-to-multipoint (P2MP) Label Switched Path (LSP) defined in
[RFC6388] allows traffic to transmit from root to several leaf nodes, [RFC6388] allows traffic to transmit from root to several leaf nodes,
and multipoint-to-multipoint (MP2MP) LSP allows traffic from every and multipoint-to-multipoint (MP2MP) LSP allows traffic from every
node to transmit to every other node. This draft introduces a hub & node to transmit to every other node. This document introduces a hub
spoke multipoint (HSMP) LSP, which has one root node and one or more and spoke multipoint (HSMP) LSP, which has one root node and one or
leaf nodes. HSMP LSP allows traffic both from root to leaf through more leaf nodes. An HSMP LSP allows traffic from root to leaf
downstream LSP and also leaf to root along the upstream LSP. That through downstream LSP and also leaf to root along the upstream LSP.
means traffic entering the HSMP LSP at the root node travels along That means traffic entering the HSMP LSP at the root node travels
downstream LSP, exactly as if it is travelling along a P2MP LSP, and along the downstream LSP, exactly as if it were traveling along a
traffic entering the HSMP LSP at any other leaf nodes travels along P2MP LSP, and traffic entering the HSMP LSP at any other leaf nodes
upstream LSP toward only the root node. The upstream LSP should be travels along the upstream LSP toward only the root node. The
thought of unicast LSP to the root node, except that it follows the upstream LSP should be thought of as a unicast LSP to the root node,
reverse direction of the downstream LSP, rather than routing protocol except that it follows the reverse direction of the downstream LSP,
based unicast path. The combination of upstream LSPs initiated from rather than the unicast path based on the routing protocol. The
all leaf nodes forms a multipoint-to-point LSP. combination of upstream LSPs initiated from all leaf nodes forms a
multipoint-to-point LSP.
2. Terminology 2. Terminology
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 [RFC2119]. document are to be interpreted as described in [RFC2119].
This document uses some terms and acronyms as follows: This document uses the following terms and acronyms:
mLDP: Multipoint extensions for Label Distribution Protocol (LDP) mLDP: Multipoint extensions for Label Distribution Protocol (LDP)
defined in [RFC6388]. defined in [RFC6388].
P2MP LSP: point-to-multipoint Label Switched Path. An LSP that P2MP LSP: point-to-multipoint Label Switched Path. An LSP that
has one Ingress Label Switching Router (LSR) and one or more has one Ingress Label Switching Router (LSR) and one or more
Egress LSRs. Egress LSRs.
MP2MP LSP: multipoint-to-multipoint Label Switched Path. An LSP MP2MP LSP: multipoint-to-multipoint Label Switched Path. An LSP
that connects a set of nodes, such that traffic sent by any node that connects a set of nodes, such that traffic sent by any node
in the LSP is delivered to all others. in the LSP is delivered to all others.
HSMP LSP: hub & spoke multipoint Label Switched Path. An LSP that HSMP LSP: hub and spoke multipoint Label Switched Path. An LSP
has one root node and one or more leaf nodes, allows traffic from that has one root node and one or more leaf nodes, allows traffic
root to all leaf nodes along downstream P2MP LSP and also leaf to from the root to all leaf nodes along the downstream P2MP LSP and
root node along the upstream unicast LSP. also leaf to root node along the upstream unicast LSP.
FEC: Forwarding Equivalence Class FEC: Forwarding Equivalence Class
3. Setting up HSMP LSP with LDP 3. Setting Up HSMP LSP with LDP
HSMP LSP is similar to MP2MP LSP described in [RFC6388], with the An HSMP LSP is similar to MP2MP LSP described in [RFC6388], with the
difference that, when the leaf LSRs send traffic on the LSP, the difference being that, when the leaf LSRs send traffic on the LSP,
traffic is first delivered only to the root node and follows the the traffic is first delivered only to the root node and follows the
upstream path from the leaf node to the root node. The root node upstream path from the leaf node to the root node. The root node
then distributes the traffic on the P2MP tree to all of the leaf then distributes the traffic on the P2MP tree to all of the leaf
nodes. nodes.
HSMP LSP consists of a downstream path and upstream path. The An HSMP LSP consists of a downstream path and upstream path. The
downstream path is same as P2MP LSP, while the upstream path is only downstream path is the same as P2MP LSP, while the upstream path is
from leaf to root node, without communication between leaf and leaf only from leaf to root node, without communication between the leaf
nodes. The transmission of packets from the root node of an HSMP LSP nodes themselves. The transmission of packets from the root node of
to the receivers (the leaf nodes) is identical to that of a P2MP LSP. an HSMP LSP to the receivers (the leaf nodes) is identical to that of
Traffic from a leaf node to the root follows the upstream path that a P2MP LSP. Traffic from a leaf node to the root follows the
is the reverse of the path from the root to the leaf. Unlike an upstream path that is the reverse of the path from the root to the
MP2MP LSP, traffic from a leaf node does not branch toward other leaf leaf. Unlike an MP2MP LSP, traffic from a leaf node does not branch
nodes, but is sent direct to the root where it is placed on the P2MP toward other leaf nodes, but it is sent direct to the root where it
path and distributed to all leaf nodes including the original sender. is placed on the P2MP path and distributed to all leaf nodes
including the original sender.
To set up the upstream path of an HSMP LSP, ordered mode MUST be To set up the upstream path of an HSMP LSP, ordered mode MUST be
used. Ordered mode can guarantee a leaf to start sending packets to used. Ordered mode can guarantee that a leaf will start sending
root immediately after the upstream path is installed, without being packets to the root immediately after the upstream path is installed,
dropped due to an incomplete LSP. without being dropped due to an incomplete LSP.
3.1. Support for HSMP LSP Setup with LDP 3.1. Support for HSMP LSP Setup with LDP
HSMP LSP requires the LDP capabilities [RFC5561] for nodes to An HSMP LSP requires the LDP capabilities [RFC5561] for nodes to
indicate that they support setup of HSMP LSPs. An implementation indicate that they support setup of HSMP LSPs. An implementation
supporting the HSMP LSP procedures specified in this document MUST supporting the HSMP LSP procedures specified in this document MUST
implement the procedures for Capability Parameters in Initialization implement the procedures for Capability Parameters in Initialization
Messages. Advertisement of the HSMP LSP Capability indicates support messages. Advertisement of the HSMP LSP Capability indicates support
of the procedures for HSMP LSP setup. of the procedures for HSMP LSP setup.
A new Capability Parameter TLV is defined, the HSMP LSP Capability A new Capability Parameter TLV is defined, the HSMP LSP Capability
Parameter. Following is the format of the HSMP LSP Capability Parameter. Below is the format of the HSMP LSP Capability Parameter.
Parameter.
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|U|F| HSMP LSP Cap(TBD IANA) | Length | |U|F| HSMP LSP Cap (0x0902) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S| Reserved | |S| Reserved |
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
Figure 1. HSMP LSP Capability Parameter encoding
U-bit: Unknown TLV bit, as described in [RFC5036]. The value MUST be Figure 1: HSMP LSP Capability Parameter Encoding
1. The unknown TLV MUST be silently ignored and the rest of the
message processed as if the unknown TLV did not exist.
F-bit: Forward unknown TLV bit, as described in [RFC5036]. The value U-bit: Unknown TLV bit, as described in [RFC5036]. The value MUST
of this bit MUST be 0 since a Capability Parameter TLV is sent only be 1. The unknown TLV MUST be silently ignored and the rest
in Initialization and Capability messages, which are not forwarded. of the message processed as if the unknown TLV did not exist.
The length SHOULD be 1, and the S bit and reserved bits are defined F-bit: Forward unknown TLV bit, as described in [RFC5036]. The
in [RFC5561] section 3. value of this bit MUST be 0 since a Capability Parameter TLV
is sent only in Initialization and Capability messages, which
are not forwarded.
The HSMP LSP Capability Parameter type is to be assigned by IANA. Length: SHOULD be 1.
S-bit: As defined in Section 3 of [RFC5561].
Reserved: As defined in Section 3 of [RFC5561].
HSMP LSP Capability Parameter type: 0x0902.
If the peer has not advertised the corresponding capability, then If the peer has not advertised the corresponding capability, then
label messages using the HSMP Forwarding Equivalence Class (FEC) label messages using the HSMP Forwarding Equivalence Class (FEC)
Element SHOULD NOT (as described in [RFC6388] section 2.1) be sent to Element SHOULD NOT be sent to the peer (as described in Section 2.1
the peer. Since ordered mode is applied for HSMP LSP signalling, the of [RFC6388]). Since ordered mode is applied for HSMP LSP signaling,
label message break would ensure that the initiating leaf node is the label message break would ensure that the initiating leaf node is
unable to establish the upstream path to root node. unable to establish the upstream path to root node.
3.2. HSMP FEC Elements 3.2. HSMP FEC Elements
Similar as MP2MP LSP, we define two new protocol entities, the HSMP We define two new protocol entities: the HSMP Downstream FEC Element
Downstream FEC Element and Upstream FEC Element. If a FEC TLV and Upstream FEC Element. If a FEC TLV contains one of the HSMP FEC
contains one of the HSMP FEC Elements, the HSMP FEC Element MUST be Elements, the HSMP FEC Element MUST be the only FEC Element in the
the only FEC Element in the FEC TLV. The structure, encoding and FEC TLV. The structure, encoding, and error handling for the HSMP-
error handling for the HSMP Downstream FEC Element and Upstream FEC downstream FEC Element and HSMP-upstream FEC Element are the same as
Element are the same as for the P2MP FEC Element described in for the P2MP FEC Element described in Section 2.2 of [RFC6388]. The
[RFC6388] Section 2.2. The difference is that two additional new FEC difference is that two additional new FEC types are defined: HSMP-
types are defined: HSMP Downstream FEC (to be assigned by IANA) and downstream FEC (10) and HSMP-upstream FEC (9).
HSMP Upstream FEC (to be assigned by IANA).
3.3. Using the HSMP FEC Elements 3.3. Using the HSMP FEC Elements
In order to describe the message processing clearly, the entries in The entries in the list below describe the processing of the HSMP FEC
the list below define the processing of the HSMP FEC Elements. Elements. Additionally, the entries defined in Section 3.3 of
Additionally, the entries defined in [RFC6388] section 3.3 are also [RFC6388] are also reused in the following sections.
reused in the following sections.
1. HSMP downstream LSP <X, Y> (or simply downstream <X, Y>): an HSMP 1. HSMP downstream LSP <X, Y> (or simply downstream <X, Y>): an
LSP downstream path with root node address X and opaque value Y. HSMP LSP downstream path with root node address X and opaque
value Y.
2. HSMP upstream LSP <X, Y> (or simply upstream <X, Y>): an HSMP LSP 2. HSMP upstream LSP <X, Y> (or simply upstream <X, Y>): an HSMP
upstream path for root node address X and opaque value Y which will LSP upstream path for root node address X and opaque value Y
be used by any of downstream node to send traffic upstream to root that will be used by any downstream node to send traffic
node. upstream to root node.
3. HSMP downstream FEC Element <X, Y>: a FEC Element with root node 3. HSMP-downstream FEC Element <X, Y>: a FEC Element with root node
address X and opaque value Y used for a downstream HSMP LSP. address X and opaque value Y used for a downstream HSMP LSP.
4. HSMP upstream FEC Element <X, Y>: a FEC Element with root node 4. HSMP-upstream FEC Element <X, Y>: a FEC Element with root node
address X and opaque value Y used for an upstream HSMP LSP. address X and opaque value Y used for an upstream HSMP LSP.
5. HSMP-D Label Mapping <X, Y, L>: A Label Mapping message with a 5. HSMP-D Label Mapping <X, Y, L>: A Label Mapping message with a
single HSMP downstream FEC Element <X, Y> and label TLV with label L. single HSMP-downstream FEC Element <X, Y> and label TLV with
Label L MUST be allocated from the per-platform label space of the label L. Label L MUST be allocated from the per-platform label
LSR sending the Label Mapping Message. space of the LSR sending the Label Mapping Message.
6. HSMP-U Label Mapping <X, Y, Lu>: A Label Mapping message with a 6. HSMP-U Label Mapping <X, Y, Lu>: A Label Mapping message with a
single HSMP upstream FEC Element <X, Y> and label TLV with label Lu. single HSMP upstream FEC Element <X, Y> and label TLV with label
Label Lu MUST be allocated from the per-platform label space of the Lu. Label Lu MUST be allocated from the per-platform label
LSR sending the Label Mapping Message. space of the LSR sending the Label Mapping Message.
7. HSMP-D Label Withdraw <X, Y, L>: a Label Withdraw message with a 7. HSMP-D Label Withdraw <X, Y, L>: a Label Withdraw message with a
FEC TLV with a single HSMP downstream FEC Element <X, Y> and label FEC TLV with a single HSMP-downstream FEC Element <X, Y> and
TLV with label L. label TLV with label L.
8. HSMP-U Label Withdraw <X, Y, Lu>: a Label Withdraw message with a 8. HSMP-U Label Withdraw <X, Y, Lu>: a Label Withdraw message with
FEC TLV with a single HSMP upstream FEC Element <X, Y> and label TLV a FEC TLV with a single HSMP-upstream FEC Element <X, Y> and
with label Lu. label TLV with label Lu.
9. HSMP-D Label Release <X, Y, L>: a Label Release message with a 9. HSMP-D Label Release <X, Y, L>: a Label Release message with a
FEC TLV with a single HSMP downstream FEC Element <X, Y> and Label FEC TLV with a single HSMP-downstream FEC Element <X, Y> and
TLV with label L. Label TLV with label L.
10. HSMP-U Label Release <X, Y, Lu>: a Label Release message with a 10. HSMP-U Label Release <X, Y, Lu>: a Label Release message with a
FEC TLV with a single HSMP upstream FEC Element <X, Y> and label TLV FEC TLV with a single HSMP-upstream FEC Element <X, Y> and label
with label Lu. TLV with label Lu.
3.4. HSMP LSP Label Map 3.4. HSMP LSP Label Map
This section specifies the procedures for originating HSMP Label This section specifies the procedures for originating HSMP Label
Mapping messages and processing received HSMP Label Mapping messages Mapping messages and processing received HSMP Label Mapping messages
for a particular HSMP LSP. The procedure of downstream HSMP LSP is for a particular HSMP LSP. The procedure of a downstream HSMP LSP is
similar as that of downstream MP2MP LSP described in [RFC6388]. When similar to that of a downstream MP2MP LSP described in [RFC6388].
LDP operates in Ordered Label Distribution Control mode [RFC5036], When LDP operates in Ordered Label Distribution Control mode
the upstream LSP will be set up by sending HSMP LSP LDP Label Mapping [RFC5036], the upstream LSP will be set up by sending an HSMP LSP LDP
message with a label which is allocated by upstream LSR to its Label Mapping message with a label that is allocated by the upstream
downstream LSR hop by hop from root to leaf node, installing the LSR to its downstream LSR hop-by-hop from root to leaf node,
upstream forwarding table by every node along the LSP. The detail installing the upstream forwarding table by every node along the LSP.
procedure of setting up upstream HSMP LSP is different with that of
upstream MP2MP LSP, and is specified in below section. The detailed procedure of setting up upstream HSMP LSP is different
than that of upstream MP2MP LSP, and it is specified in the remainder
of this section.
All labels discussed here are downstream-assigned [RFC5332] except All labels discussed here are downstream-assigned [RFC5332] except
those which are assigned using the procedures described in Section 4. those that are assigned using the procedures described in Section 4.
Determining the upstream LSR for the HSMP LSP <X, Y> follows the Determining the upstream LSR for the HSMP LSP <X, Y> follows the
procedure for a P2MP LSP described in [RFC6388] Section 2.4.1.1. procedure for a P2MP LSP described in Section 2.4.1.1 of [RFC6388].
That is, a node Z that wants to join an HSMP LSP <X, Y> determines That is, a node Z that wants to join an HSMP LSP <X, Y> determines
the LDP peer U that is Z's next-hop on the best path from Z to the the LDP peer U that is Z's next hop on the best path from Z to the
root node X. If there are multiple upstream LSRs, local algorithm root node X. If there are multiple upstream LSRs, a local algorithm
should be applied to ensure that there is a single upstream LSRs for should be applied to ensure that there is exactly one upstream LSR
a particular LSP. for a particular LSP.
To determining one's HSMP downstream LSR, an upstream LDP peer which To determine one's HSMP downstream LSR, an upstream LDP peer that
receives a Label Mapping with HSMP downstream FEC Element from an LDP receives a Label Mapping with the HSMP-downstream FEC Element from an
peer D will treat D as HSMP downstream LDP peer. LDP peer D will treat D as HSMP downstream LDP peer.
3.4.1. HSMP LSP Leaf Node Operation 3.4.1. HSMP LSP Leaf Node Operation
The leaf node operation is much the same as the operation of MP2MP The leaf node operation is much the same as the operation of MP2MP
LSP defined in [RFC6388] Section 3.3.1.4. The only difference is the LSP defined in Section 3.3.1.4 of [RFC6388]. The only difference is
FEC elements as specified below. the FEC elements as specified below.
A leaf node Z of an HSMP LSP <X, Y> determines its upstream LSR U for A leaf node Z of an HSMP LSP <X, Y> determines its upstream LSR U for
<X, Y> as per Section 3.3, allocates a label L, and sends an HSMP-D <X, Y> as per Section 3.3, allocates a label L, and sends an HSMP-D
Label Mapping <X, Y, L> to U. Leaf node Z expects an HSMP-U Label Label Mapping <X, Y, L> to U. Leaf node Z expects an HSMP-U Label
Mapping <X, Y, Lu> from node U and checks whether it already has Mapping <X, Y, Lu> from node U and checks whether it already has
forwarding state for upstream <X, Y>. If not, Z creates forwarding forwarding state for upstream <X, Y>. If not, Z creates forwarding
state to push label Lu onto the traffic that Z wants to forward over state to push label Lu onto the traffic that Z wants to forward over
the HSMP LSP. How it determines what traffic to forward on this HSMP the HSMP LSP. How it determines what traffic to forward on this HSMP
LSP is outside the scope of this document. LSP is outside the scope of this document.
3.4.2. HSMP LSP Transit Node Operation 3.4.2. HSMP LSP Transit Node Operation
The procedure of HSMP-D Label Mapping message is much the same as The procedure for processing an HSMP-D Label Mapping message is much
processing MP2MP-D Label Mapping message defined in [RFC6388] Section the same as that for an MP2MP-D Label Mapping message defined in
3.3.1.5. The processing of HSMP-U Label Mapping message is different Section 3.3.1.5 of [RFC6388]. The processing of an HSMP-U Label
with that of MP2MP-U Label Mapping message as specified below. Mapping message is different from that of an MP2MP-U Label Mapping
message as specified below.
Suppose node Z receives an HSMP-D Label Mapping <X, Y, L> from LSR D. Suppose node Z receives an HSMP-D Label Mapping <X, Y, L> from LSR D.
Z checks whether it has forwarding state for downstream <X, Y>. If Z checks whether it has forwarding state for downstream <X, Y>. If
not, Z determines its upstream LSR U for <X, Y> as per Section 3.3. not, Z determines its upstream LSR U for <X, Y> as per Section 3.3.
Using this Label Mapping to update the label forwarding table MUST Using this Label Mapping to update the label forwarding table MUST
NOT be done as long as LSR D is equal to LSR U. If LSR U is different NOT be done as long as LSR D is equal to LSR U. If LSR U is
from LSR D, Z will allocate a label L' and install downstream different from LSR D, Z will allocate a label L' and install
forwarding state to swap label L' with label L over interface I downstream forwarding state to swap label L' with label L over
associated with LSR D and send an HSMP-D Label Mapping <X, Y, L'> to interface I associated with LSR D and send an HSMP-D Label Mapping
U. Interface I is determined via the procedures in Section 3.7. <X, Y, L'> to U. Interface I is determined via the procedures in
Section 3.7.
If Z already has forwarding state for downstream <X, Y>, all that Z If Z already has forwarding state for downstream <X, Y>, all that Z
needs to do in this case is check that LSR D is not equal to the needs to do in this case is check that LSR D is not equal to the
upstream LSR of <X, Y> and update its forwarding state. Assuming its upstream LSR of <X, Y> and update its forwarding state. Assuming its
old forwarding state was L'-> {<I1, L1> <I2, L2> ..., <In, Ln>}, its old forwarding state was L'-> {<I1, L1> <I2, L2> ..., <In, Ln>}, its
new forwarding state becomes L'-> {<I1, L1> <I2, L2> ..., <In, Ln>, new forwarding state becomes L'-> {<I1, L1> <I2, L2> ..., <In, Ln>,
<I, L>}. If the LSR D is equal to the installed upstream LSR, the <I, L>}. If the LSR D is equal to the installed upstream LSR, the
Label Mapping from LSR D MUST be retained and MUST NOT update the Label Mapping from LSR D MUST be retained and MUST NOT update the
label forwarding table. label forwarding table.
Node Z checks if upstream LSR U already has assigned a label Lu to Node Z checks if the upstream LSR U already has assigned a label Lu
upstream <X, Y>. If not, transit node Z waits until it receives an to upstream <X, Y>. If not, transit node Z waits until it receives
HSMP-U Label Mapping <X, Y, Lu> from LSR U. Once the HSMP-U Label an HSMP-U Label Mapping <X, Y, Lu> from LSR U. Once the HSMP-U Label
Mapping is received from LSR U, node Z checks whether it already has Mapping is received from LSR U, node Z checks whether it already has
forwarding state upstream <X, Y> with incoming label Lu' and outgoing forwarding state upstream <X, Y> with incoming label Lu' and outgoing
label Lu. If it does not, it allocates a label Lu' and creates a new label Lu. If it does not, it allocates a label Lu' and creates a new
label swap for Lu' with Label Lu over interface Iu. Interface Iu is label swap for Lu' with Label Lu over interface Iu. Interface Iu is
determined via the procedures in Section 3.7. Node Z determines the determined via the procedures in Section 3.7. Node Z determines the
downstream HSMP LSR as per Section 4.3.1, and sends an HSMP-U Label downstream HSMP LSR as per Section 3.4 and sends an HSMP-U Label
Mapping <X, Y, Lu'> to node D. Mapping <X, Y, Lu'> to node D.
Since a packet from any downstream node is forwarded only to the Since a packet from any downstream node is forwarded only to the
upstream node, the same label (representing the upstream path) SHOULD upstream node, the same label (representing the upstream path) SHOULD
be distributed to all downstream nodes. This differs from the be distributed to all downstream nodes. This differs from the
procedures for MP2MP LSPs [RFC6388], where a distinct label must be procedures for MP2MP LSPs [RFC6388], where a distinct label must be
distributed to each downstream node. The forwarding state upstream distributed to each downstream node. The forwarding state upstream
<X, Y> on node Z will be like this {<Lu'>, <Iu Lu>}. Iu means the <X, Y> on node Z will be like this: {<Lu'>, <Iu Lu>}. Iu means the
upstream interface over which Z receives HSMP-U Label Map <X, Y, Lu> upstream interface over which Z receives HSMP-U Label Map <X, Y, Lu>
from LSR U. Packets from any downstream interface over which Z sends from LSR U. Packets from any downstream interface over which Z sends
HSMP-U Label Map <X, Y, Lu'> with label Lu' will be forwarded to Iu HSMP-U Label Map <X, Y, Lu'> with label Lu' will be forwarded to Iu
with label Lu' swap to Lu. with label Lu' swapped to Lu.
3.4.3. HSMP LSP Root Node Operation 3.4.3. HSMP LSP Root Node Operation
The procedure of HSMP-D Label Mapping message is much the same as The procedure for an HSMP-D Label Mapping message is much the same as
processing MP2MP-D Label Mapping message defined in [RFC6388] Section processing an MP2MP-D Label Mapping message defined in
3.3.1.6. The processing of HSMP-U Label Mapping message is different Section 3.3.1.6 of [RFC6388]. The processing of an HSMP-U Label
with that of MP2MP-U Label Mapping message as specified below. Mapping message is different from that of an MP2MP-U Label Mapping
message as specified below.
Suppose the root node Z receives an HSMP-D Label Mapping <X, Y, L> Suppose the root node Z receives an HSMP-D Label Mapping <X, Y, L>
from node D. Z checks whether it already has forwarding state for from node D. Z checks whether it already has forwarding state for
downstream <X, Y>. If not, Z creates downstream forwarding state and downstream <X, Y>. If not, Z creates downstream forwarding state and
installs a outgoing label L over interface I. Interface I is installs an outgoing label L over interface I. Interface I is
determined via the procedures in Section 3.7. If Z already has determined via the procedures in Section 3.7. If Z already has
forwarding state for downstream <X, Y>, then Z will add label L over forwarding state for downstream <X, Y>, then Z will add label L over
interface I to the existing state. interface I to the existing state.
Node Z checks if it has forwarding state for upstream <X, Y>. If Node Z checks if it has forwarding state for upstream <X, Y>. If
not, Z creates a forwarding state for incoming label Lu' that not, Z creates a forwarding state for incoming label Lu' that
indicates that Z is the HSMP LSP egress LER. E.g., the forwarding indicates that Z is the HSMP LSP egress Label Edge Router (LER). For
state might specify that the label stack is popped and the packet example, the forwarding state might specify that the label stack is
passed to some specific application. Node Z determines the popped and the packet passed to some specific application. Node Z
downstream HSMP LSR as per Section 3.3, and sends an HSMP-U Label Map determines the downstream HSMP LSR as per Section 3.3 and sends an
<X, Y, Lu'> to node D. HSMP-U Label Map <X, Y, Lu'> to node D.
Since Z is the root of the tree, Z will not send an HSMP-D Label Map Since Z is the root of the tree, Z will not send an HSMP-D Label Map
and will not receive an HSMP-U Label Mapping. and will not receive an HSMP-U Label Mapping.
Root node could also be a leaf node, and it is able to determine what The root node could also be a leaf node, and it is able to determine
traffic to forward on this HSMP LSP which is outside the scope of what traffic to forward on this HSMP LSP; that determination is
this document. outside the scope of this document.
3.5. HSMP LSP Label Withdraw 3.5. HSMP LSP Label Withdraw
3.5.1. HSMP Leaf Operation 3.5.1. HSMP Leaf Operation
If a leaf node Z discovers that it has no need to be an Egress LSR If a leaf node Z discovers that it has no need to be an Egress LSR
for that LSP (by means outside the scope of this document), then it for that LSP (by means outside the scope of this document), then it
SHOULD send an HSMP-D Label Withdraw <X, Y, L> to its upstream LSR U SHOULD send an HSMP-D Label Withdraw <X, Y, L> to its upstream LSR U
for <X, Y>, where L is the label it had previously advertised to U for <X, Y>, where L is the label it had previously advertised to U
for <X,Y>. Leaf node Z will also send an unsolicited HSMP-U Label for <X, Y>. Leaf node Z will also send an unsolicited HSMP-U Label
Release <X, Y, Lu> to U to indicate that the upstream path is no Release <X, Y, Lu> to U to indicate that the upstream path is no
longer used and that label Lu can be removed. longer used and that label Lu can be removed.
Leaf node Z expects the upstream router U to respond by sending a Leaf node Z expects the upstream router U to respond by sending a
downstream Label Release for L. downstream Label Release for L.
3.5.2. HSMP Transit Node Operation 3.5.2. HSMP Transit Node Operation
If a transit node Z receives an HSMP-D Label Withdraw message <X, Y, If a transit node Z receives an HSMP-D Label Withdraw message
L> from node D, it deletes label L from its forwarding state <X, Y, L> from node D, it deletes label L from its forwarding state
downstream <X, Y>. Node Z sends an HSMP-D Label Release message with downstream <X, Y>. Node Z sends an HSMP-D Label Release message with
label L to D. There is no need to send an HSMP-U Label Withdraw <X, label L to D. There is no need to send an HSMP-U Label Withdraw <X,
Y, Lu> to D because node D already removed Lu and sent a label Y, Lu> to D because node D already removed Lu and sent a label
release for Lu to Z. release for Lu to Z.
If deleting L from Z's forwarding state for downstream <X, Y> results If deleting L from Z's forwarding state for downstream <X, Y> results
in no state remaining for <X, Y>, then Z propagates the HSMP-D Label in no state remaining for <X, Y>, then Z propagates the HSMP-D Label
Withdraw <X, Y, L> to its upstream node U for <X, Y>. Z should also Withdraw <X, Y, L> to its upstream node U for <X, Y>. Z should also
check if there are any incoming interface in forwarding state check if there are any incoming interfaces in forwarding state
upstream <X, Y>. If all downstream nodes are released and there is upstream <X, Y>. If all downstream nodes are released and there is
no incoming interface, Z should delete the forwarding state upstream no incoming interface, Z should delete the forwarding state upstream
<X, Y> and send HSMP-U Label Release message to its upstream node. <X, Y> and send an HSMP-U Label Release message to its upstream node.
Otherwise, no HSMP-U Label Release message will be sent to the Otherwise, no HSMP-U Label Release message will be sent to the
upstream node. upstream node.
3.5.3. HSMP Root Node Operation 3.5.3. HSMP Root Node Operation
When the root node of an HSMP LSP receives an HSMP-D Label Withdraw When the root node of an HSMP LSP receives an HSMP-D Label Withdraw
and HSMP-U Label Release message, the procedure is the same as that message and an HSMP-U Label Release message, the procedure is the
for transit nodes, except that the root node will not propagate the same as that for transit nodes, except that the root node will not
Label Withdraw and Label Release upstream (as it has no upstream). propagate the Label Withdraw and Label Release upstream (as it has no
upstream).
3.6. HSMP LSP Upstream LSR Change 3.6. HSMP LSP Upstream LSR Change
The procedure for changing the upstream LSR is the same as defined in The procedure for changing the upstream LSR is the same as defined in
[RFC6388] Section 2.4.3, only with different processing FEC Element. Section 2.4.3 of [RFC6388], only with different processing of the FEC
Element.
When the upstream LSR changes from U to U', node Z should set up the When the upstream LSR changes from U to U', node Z should set up the
HSMP LSP <X, Y> to U' by applying procedures in Section 3.4. Z will HSMP LSP <X, Y> to U' by applying the procedures in Section 3.4. Z
also remove HSMP LSP <X, Y> to U by applying procedure in Section will also remove the HSMP LSP <X, Y> to U by applying the procedure
3.5. in Section 3.5.
To set up HSMP LSP to U' before/after removing HSMP LSP to U is a To set up an HSMP LSP to U' before/after removing the HSMP LSP to U
local matter, and the recommended default behavior is to remove is a local matter. The recommended default behavior is to remove
before adding. before adding.
3.7. Determining Forwarding Interface 3.7. Determining Forwarding Interface
The co-routed path between upstream and downstream LSP would be The upstream and downstream LSPs can be co-routed by applying the
achieved for HSMP LSP. Both LSR U and LSR D would ensure the same procedures below. Both LSR U and LSR D would ensure that the same
interface to send traffic by applying some procedures. For a network interface sends traffic by applying some procedures. For a network
with symmetric IGP cost configuration, the following procedure MAY be with symmetric IGP cost configuration, the following procedure MAY be
used. To determine the downstream interface, LSR U MUST do a lookup used. To determine the downstream interface, LSR U MUST do a lookup
in the unicast routing table to find the best interface and next-hop in the unicast routing table to find the best interface and next hop
to reach LSR D. If the next-hop and interface are also advertised by to reach LSR D. If the next hop and interface are also advertised by
LSR D via the LDP session, it should be used to transmit the packet LSR D via the LDP session, it should be used to transmit the packet
to LSR D. Determine the upstream interface mechanism is same as to LSR D. The mechanism to determine the upstream interface is the
determining the downstream interface by exchanging the role of LSR U same as that used to determine the downstream interface except the
and LSR D. If symmetric IGP cost could not be ensured, static route roles of LSR U and LSR D are switched. If symmetric IGP cost could
configuration on LSR U and D could also be a possible way to ensure not be ensured, static route configuration on LSR U and D could also
co-routed path. be a way to ensure a co-routed path.
If co-routed is not required for HSMP LSP, the procedure defined in If a co-routed path is not required for the HSMP LSP, the procedure
[RFC6388] Section 2.4.1.2 could be applied. LSR U is free to defined in Section 2.4.1.2 of [RFC6388] could be applied. LSR U is
transmit the packet on any of the interfaces to LSR D. The algorithm free to transmit the packet on any of the interfaces to LSR D. The
it uses to choose a particular interface is a local matter. algorithm it uses to choose a particular interface is a local matter.
Determine the upstream interface mechanism is the same as determining
the downstream interface. The mechanism to determine the upstream interface is the same as that
used to determine the downstream interface.
4. HSMP LSP on a LAN 4. HSMP LSP on a LAN
The procedure to process the downstream HSMP LSP on a LAN is much the The procedure to process the downstream HSMP LSP on a LAN is much the
same as downstream MP2MP LSP described in [RFC6388] section 6.1.1. same as for a downstream MP2MP LSP as described in Section 6.1.1 of
[RFC6388].
When establishing the downstream path of an HSMP LSP, as defined in When establishing the downstream path of an HSMP LSP, as defined in
[RFC6389], a Label Request message for an LSP label is sent to the [RFC6389], a Label Request message for an LSP label is sent to the
upstream LSR. The upstream LSR should send Label Mapping message upstream LSR. The upstream LSR should send a Label Mapping message
that contains the LSP label for the downstream HSMP FEC and the that contains the LSP label for the downstream HSMP FEC and the
upstream LSR context label defined in [RFC5331]. When the LSR upstream LSR context label defined in [RFC5331]. When the LSR
forwards a packet downstream on one of those LSPs, the packet's top forwards a packet downstream on one of those LSPs, the packet's top
label must be the "upstream LSR context label", and the packet's label must be the "upstream LSR context label" and the packet's
second label is "LSP label". The HSMP downstream path will be second label is the "LSP label". The HSMP downstream path will be
installed in the context-specific forwarding table corresponding to installed in the context-specific forwarding table corresponding to
the upstream LSR label. Packets sent by the upstream LSR can be the upstream LSR label. Packets sent by the upstream LSR can be
forwarded downstream using this forwarding state based on a two-label forwarded downstream using this forwarding state based on a two-label
lookup. lookup.
The upstream path of an HSMP LSP on a LAN is the same as the one on The upstream path of an HSMP LSP on a LAN is the same as the one on
other kind of links. That is, the upstream LSR must send Label other kinds of links. That is, the upstream LSR must send a Label
Mapping message that contains the LSP label for upstream HSMP FEC to Mapping message that contains the LSP label for the upstream HSMP FEC
downstream node. Packets travelling upstream need to be forwarded in to the downstream node. Packets traveling upstream need to be
the direction of the root by using the label allocated for upstream forwarded in the direction of the root by using the label allocated
HSMP FEC. for the upstream HSMP FEC.
5. Redundancy Considerations 5. Redundancy Considerations
In some scenarios, it is necessary to provide two root nodes for In some scenarios, it is necessary to provide two root nodes for
redundancy purpose. One way to implement this is to use two redundancy purposes. One way to implement this is to use two
independent HSMP LSPs acting as active/standby. At one time, only independent HSMP LSPs acting as active and standby. At a given time,
one HSMP LSP will be active, and the other will be standby. After only one HSMP LSP will be active; the other will be standby. After
detecting the failure of active HSMP LSP, the root and leaf nodes detecting the failure of the active HSMP LSP, the root and leaf nodes
will switch the traffic to the standby HSMP LSP which takes on the will switch the traffic to the standby HSMP LSP, which takes on the
role as active HSMP LSP. The detail of redundancy mechanism is out role as active HSMP LSP. The details of the redundancy mechanism are
of the scope. out of the scope of this document.
6. Failure Detection of HSMP LSP 6. Failure Detection of HSMP LSP
The idea of LSP ping for HSMP LSPs could be expressed as an intention The idea of LSP ping for HSMP LSPs could be expressed as an intention
to test the LSP Ping Echo Request packets that enter at the root to test the LSP Ping Echo Request packets that enter at the root
along a particular downstream path of HSMP LSP, and end their MPLS along a particular downstream path of HSMP LSP and that end their
path on the leaf. The leaf node then sends the LSP Ping Echo Reply MPLS path on the leaf. The leaf node then sends the LSP Ping Echo
along the upstream path of HSMP LSP, and end on the root that are the Reply along the upstream path of HSMP LSP, and it ends on the root
(intended) root node. that is the (intended) root node.
New sub-TLVs are required to be assigned by IANA in Target FEC Stack New sub-TLVs have been assigned by IANA in Target FEC Stack TLV and
TLV and Reverse-path Target FEC Stack TLV to define the corresponding Reverse-path Target FEC Stack TLV to define the corresponding HSMP-
HSMP-downstream FEC type and HSMP-upstream FEC type. In order to downstream FEC type and HSMP-upstream FEC type. In order to ensure
ensure the leaf node to send the LSP Ping Echo Reply along the HSMP that the leaf node sends the LSP Ping Echo Reply along the HSMP
upstream path, the R bit (Validate Reverse Path) in Global Flags upstream path, the R flag (Validate Reverse Path) in the Global Flags
Field defined in [RFC6426] is reused here. field defined in [RFC6426] is reused here.
The node processing mechanism of LSP Ping Echo Request and Echo Reply The node-processing mechanism of LSP Ping Echo Request and Echo Reply
for HSMP LSP is inherited from [RFC6425] and [RFC6426] Section 3.4, for the HSMP LSP is inherited from [RFC6425] and Section 3.4 of
except the following: [RFC6426], except for the following:
1. The root node sending LSP Ping Echo Request message for HSMP LSP 1. The root node sending the LSP Ping Echo Request message for the
MUST attach Target FEC Stack with HSMP downstream FEC, and set R bit HSMP LSP MUST attach the Target FEC Stack TLV with the HSMP-
to '1' in Global Flags Field. downstream FEC type, and set the R flag to '1' in the Global
Flags field.
2. When the leaf node receiving the LSP Ping Echo Request, it MUST 2. When the leaf node receives the LSP Ping Echo Request, it MUST
send the LSP Ping Echo Reply to the associated HSMP upstream path. send the LSP Ping Echo Reply to the associated HSMP upstream
The Reverse-path Target FEC Stack TLV attached by leaf node in Echo path. The Reverse-path Target FEC Stack TLV attached by the leaf
Reply message SHOULD contain the sub-TLV of associated HSMP upstream node in the Echo Reply message SHOULD contain the sub-TLV of the
FEC. associated HSMP-upstream FEC.
7. Security Considerations 7. Security Considerations
The same security considerations apply as for the MP2MP LSP described The same security considerations apply as for the MP2MP LSP described
in [RFC6388] and [RFC6425]. in [RFC6388] and [RFC6425].
Although this document introduces new FEC Elements and corresponding Although this document introduces new FEC Elements and corresponding
procedures, the protocol does not bring any new security issues procedures, the protocol does not bring any new security issues
compared to [RFC6388] and [RFC6425]. beyond those in [RFC6388] and [RFC6425].
8. IANA Considerations 8. IANA Considerations
8.1. New LDP FEC Element types 8.1. New LDP FEC Element Types
This document requires allocation of two new LDP FEC Element types Two new LDP FEC Element types have been allocated from the "Label
from the "Label Distribution Protocol (LDP) Parameters registry" the Distribution Protocol (LDP) Parameters" registry, under "Forwarding
"Forwarding Equivalence Class (FEC) Type Name Space": Equivalence Class (FEC) Type Name Space":
1. the HSMP-upstream FEC type - requested value TBD 1. the HSMP-upstream FEC type - 9
2. the HSMP-downstream FEC type - requested value TBD 2. the HSMP-downstream FEC type - 10
The values should be allocated using the lowest free values from the The values have been allocated from the "IETF Consensus" [RFC5226]
"IETF Consensus"-range (0-127). range (0-127).
8.2. HSMP LSP capability TLV 8.2. HSMP LSP Capability TLV
This document requires allocation of one new code points for the HSMP One new code point has been allocated for the HSMP LSP capability TLV
LSP capability TLV from "Label Distribution Protocol (LDP) Parameters from "Label Distribution Protocol (LDP) Parameters" registry, under
registry" the "TLV Type Name Space": "TLV Type Name Space":
HSMP LSP Capability Parameter - requested value TBD HSMP LSP Capability Parameter - 0x0902
The value should be allocated from the range 0x0901-0x3DFF (IETF The value has been allocated from the"IETF Consensus" range
Consensus) using the first free value within this range. (0x0901-0x3DFF).
8.3. New sub-TLVs for the Target Stack TLV 8.3. New Sub-TLVs for the Target Stack TLV
This document requires allocation of two new sub-TLV types for Two new sub-TLV types have been allocated for inclusion within the
inclusion within the LSP ping [RFC4379] Target FEC Stack TLV (TLV LSP ping [RFC4379] Target FEC Stack TLV (TLV type 1), Reverse-path
type 1) and Reverse-path Target FEC Stack TLV (TLV type 16). Target FEC Stack TLV (TLV type 16), and Reply Path TLV (TLV type 21).
1. the HSMP-upstream LDP FEC Stack - requested value TBD o the HSMP-upstream LDP FEC Stack - 29
2. the HSMP-downstream LDP FEC Stack - requested value TBD o the HSMP-downstream LDP FEC Stack - 30
The value should be allocated from the IETF Standards Action range The value has been allocated from the "IETF Standards Action" range
(0-16383) that is used for mandatory and optional sub-TLVs that (0-16383) that is used for mandatory and optional sub-TLVs that
requires a response if not understood. The value should be allocated requires a response if not understood.
using the lowest free value within this range.
9. Acknowledgement 9. Acknowledgements
The author would like to thank Eric Rosen, Sebastien Jobert, Fei Su, The author would like to thank Eric Rosen, Sebastien Jobert, Fei Su,
Edward, Mach Chen, Thomas Morin, Loa Andersson for their valuable Edward, Mach Chen, Thomas Morin, and Loa Andersson for their valuable
comments. comments.
10. References 10. References
10.1. Normative references 10.1. Normative References
[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.
[RFC5331] Aggarwal, R., Rekhter, Y., and E. Rosen, "MPLS Upstream [RFC5331] Aggarwal, R., Rekhter, Y., and E. Rosen, "MPLS Upstream
Label Assignment and Context-Specific Label Space", Label Assignment and Context-Specific Label Space", RFC
RFC 5331, August 2008. 5331, August 2008.
[RFC5332] Eckert, T., Rosen, E., Aggarwal, R., and Y. Rekhter, "MPLS [RFC5332] Eckert, T., Rosen, E., Aggarwal, R., and Y. Rekhter, "MPLS
Multicast Encapsulations", RFC 5332, August 2008. Multicast Encapsulations", RFC 5332, August 2008.
[RFC5561] Thomas, B., Raza, K., Aggarwal, S., Aggarwal, R., and JL. [RFC5561] Thomas, B., Raza, K., Aggarwal, S., Aggarwal, R., and JL.
Le Roux, "LDP Capabilities", RFC 5561, July 2009. Le Roux, "LDP Capabilities", RFC 5561, July 2009.
[RFC6388] Wijnands, IJ., Minei, I., Kompella, K., and B. Thomas, [RFC6388] Wijnands, IJ., Minei, I., Kompella, K., and B. Thomas,
"Label Distribution Protocol Extensions for Point-to- "Label Distribution Protocol Extensions for Point-to-
Multipoint and Multipoint-to-Multipoint Label Switched Multipoint and Multipoint-to-Multipoint Label Switched
Paths", RFC 6388, November 2011. Paths", RFC 6388, November 2011.
[RFC6389] Aggarwal, R. and JL. Le Roux, "MPLS Upstream Label [RFC6389] Aggarwal, R. and JL. Le Roux, "MPLS Upstream Label
Assignment for LDP", RFC 6389, November 2011. Assignment for LDP", RFC 6389, November 2011.
[RFC6425] Saxena, S., Swallow, G., Ali, Z., Farrel, A., Yasukawa, [RFC6425] Saxena, S., Swallow, G., Ali, Z., Farrel, A., Yasukawa,
S., and T. Nadeau, "Detecting Data-Plane Failures in S., and T. Nadeau, "Detecting Data-Plane Failures in
Point-to-Multipoint MPLS - Extensions to LSP Ping", Point-to-Multipoint MPLS - Extensions to LSP Ping", RFC
RFC 6425, November 2011. 6425, November 2011.
[RFC6426] Gray, E., Bahadur, N., Boutros, S., and R. Aggarwal, "MPLS [RFC6426] Gray, E., Bahadur, N., Boutros, S., and R. Aggarwal, "MPLS
On-Demand Connectivity Verification and Route Tracing", On-Demand Connectivity Verification and Route Tracing",
RFC 6426, November 2011. RFC 6426, November 2011.
10.2. Informative References 10.2. Informative References
[RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol [RFC4379] Kompella, K. and G. Swallow, "Detecting Multi-Protocol
Label Switched (MPLS) Data Plane Failures", RFC 4379, Label Switched (MPLS) Data Plane Failures", RFC 4379,
February 2006. February 2006.
[RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP [RFC5036] Andersson, L., Minei, I., and B. Thomas, "LDP
Specification", RFC 5036, October 2007. Specification", RFC 5036, October 2007.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
Authors' Addresses Authors' Addresses
Lizhong Jin Lizhong Jin
Shanghai, China Shanghai
China
Email: lizho.jin@gmail.com EMail: lizho.jin@gmail.com
Frederic Jounay Frederic Jounay
France Telecom Orange CH
2, avenue Pierre-Marzin 4 rue du Caudray
22307 Lannion Cedex, FRANCE 1007 Lausanne
Switzerland
Email: frederic.jounay@orange.ch EMail: frederic.jounay@orange.ch
IJsbrand Wijnands IJsbrand Wijnands
Cisco Systems, Inc Cisco Systems, Inc
De kleetlaan 6a De kleetlaan 6a
Diegem 1831, Belgium Diegem 1831
Belgium
EMail: ice@cisco.com
Email: ice@cisco.com
Nicolai Leymann Nicolai Leymann
Deutsche Telekom AG Deutsche Telekom AG
Winterfeldtstrasse 21 Winterfeldtstrasse 21
Berlin 10781 Berlin 10781
Germany
Email: N.Leymann@telekom.de EMail: N.Leymann@telekom.de
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