Network Working Group H. Bidgoli, Ed.
Internet-Draft Nokia
Intended status: Standards Track V. Voyer
Expires: May 1, 2021 Bell Canada
A. Stone
Nokia
P. Parekh
Cisco System
S. Krier
A. Venkateswaran
Cisco System, Inc.
October 28, 2020
Advertising p2mp policies in BGP
draft-hb-idr-sr-p2mp-policy-01
Abstract
SR P2MP policies are set of policies that enable architecture for
P2MP service delivery.
A P2MP policy consists of candidate paths that connects the Root of
the Tree to a set of Leaves. The P2MP policy is composed of
replication segments. A replication segment is a forwarding
instruction for a candidate path which is downloaded to the Root,
transit nodes and the leaves.
This document specifies a new BGP SAFI with a new NLRI in order to
advertise P2MP policy from a controller to a set of nodes.
This document introduces two new route types within this NLRI, one
for P2MP policy and its candidate paths that need to be programmed on
the Root node and another for the replication segment and forwarding
instructions that needs to be programmed on the Root, and optionally
on Transit and Leaf nodes.
It should be noted that this document does not specify how the Root
and the Leaves are discovered on the controller, it only describes
how the P2MP Policy and Replication Segments are programmed from the
controller to the nodes.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . 4
3. P2MP Policy and Replication Segment Encoding . . . . . . . . 4
3.1. P2MP Policy SAFI and NLRI . . . . . . . . . . . . . . . . 4
3.1.1. P2MP Policy Route . . . . . . . . . . . . . . . . . . 5
3.1.2. Non-shared Tree Replication segment Route . . . . . . 6
3.1.3. Shared Tree Replication Segment Route . . . . . . . . 6
3.2. Tunnel Encapsulation Attribute . . . . . . . . . . . . . 6
3.2.1. SR P2MP policy encoding . . . . . . . . . . . . . . . 7
3.2.2. replication segment encoding . . . . . . . . . . . . 7
3.3. P2MP Policy Sub-TLVs . . . . . . . . . . . . . . . . . . 8
3.3.1. preference Sub-TLV . . . . . . . . . . . . . . . . . 8
3.3.2. leaf-list Sub-TLV . . . . . . . . . . . . . . . . . . 8
3.3.3. path-instance Sub-TLV . . . . . . . . . . . . . . . . 9
3.3.3.1. active instance-id Sub-TLV . . . . . . . . . . . 10
3.3.3.2. instance-id Sub-TLV . . . . . . . . . . . . . . . 10
3.4. replication segment Sub-TLVs . . . . . . . . . . . . . . 11
3.4.1. Replication SID (Binding SID) . . . . . . . . . . . . 11
3.4.2. down stream nodes Sub-TLV . . . . . . . . . . . . . . 11
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3.4.3. segment list Sub-TLV . . . . . . . . . . . . . . . . 12
3.4.4. segment Sub-TLV . . . . . . . . . . . . . . . . . . . 12
4. P2MP Policy Operation . . . . . . . . . . . . . . . . . . . . 13
4.1. Configuration and advertisement of P2MP Policies . . . . 13
4.2. Reception of an P2MP Policy NLRI . . . . . . . . . . . . 14
4.3. Global Optimization for P2MP LSPs . . . . . . . . . . . . 14
5. IANA Consideration . . . . . . . . . . . . . . . . . . . . . 14
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
The draft [draft-ietf-pim-sr-p2mp-policy] defines a variant of the SR
Policy [draft-ietf-spring-segment-routing-policy] for constructing a
P2MP segment to support multicast service delivery.
A Point-to-Multipoint (P2MP) Policy contains a set of candidate paths
and identifies a Root node and a set of Leaf nodes in a Segment
Routing Domain. The draft also defines a Replication segment, which
corresponds to the state of a P2MP segment on a particular node. The
Replication segment is the forwarding instruction for a P2MP LSP at
the Root, Transit and Leaf nodes.
For a P2MP segment, a controller may be used to compute a tree from a
Root node to a set of Leaf nodes, optionally via a set of replication
nodes. A packet is replicated at the root node and optionally on
Replication nodes towards each Leaf node.
We define two types of a P2MP segment: Spray and Replication.
A Point-to-Multipoint service delivery could be via Ingress
Replication (aka Spray in some SR context), i.e., the root unicasts
individual copies of traffic to each leaf. The corresponding P2MP
segment consists of replication segments only for the root and the
leaves.
A Point-to-Multipoint service delivery could also be via Downstream
Replication (aka TreeSID in some SR context), i.e., the root and some
downstream replication nodes replicate the traffic along the way as
it traverses closer to the leaves.
It should be noted that two replication nodes can be connected
directly, or they can be connected via unicast SR segment or a
segment list.
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The leaves and the root of a p2mp policy can be discovered via the
multicast protocols or procedures like NG-MVPN [RFC6513] or manually
configured on the PCC (CLI) or the PCE.
Base on the discovered root and leaves the controller builds a P2MP
policy and advertise it to the head-end router (i.e. the root of the
P2MP Tree). The advertisement uses BGP extensions defined in this
document. In addition, the controller builds the replication
segments on each segment of the tree, Root, Transit and Leaf nodes
and downloads the forwarding instructions to the nodes via BGP
extensions defined in this document.
As it was mentioned a SR p2mp policy is a variant of the SR policy
and as such it reuses the concept of a candidate path. This draft
reuses some of the concepts and TLVs mentioned in
[draft-ietf-idr-segment-routing-te-policy]
A candidate path with in the P2MP policy can contain multiple path-
instances. A path-instance can be viewed as a P2MP LSP. For
candidate path global optimization purposes two or more path-
instances can be used to execute make before break procedures.
Each path-instance is a P2MP LSP as such each path-instance needs a
set of replication segments to construct its forwarding instructions.
2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
3. P2MP Policy and Replication Segment Encoding
3.1. P2MP Policy SAFI and NLRI
This document defines a new BGP NLRI, called the P2MP-POLICY NLRI.
A new SAFI is defined: the SR P2MP Policy SAFI, (Codepoint tbd
assigned by IANA). The following is the format of the P2MP-POLICY
NLRI:
+-----------------------------------+
| route type | 1 octet
+-----------------------------------+
| length | 1 octet
+-----------------------------------+
| route type specific (variable) |
+-----------------------------------+
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o The Route type field defines the encoding of the rest of the P2MP-
POLICY NLRI.
o The length field indicates the length in octets of the route type.
o This document defines the following route types:
* 2MP Policy route
* Non-Shared Replication Segment
* Shared Replication Segment
The NLRI containing the SR P2MP Policy is carried in a BGP UPDATE
message [RFC4271] using BGP multiprotocol extensions [RFC4760] with
an AFI of 1 or 2 (IPv4 or IPv6) and with a SAFI of "TBD" (assigned by
IANA from the "Subsequent Address Family Identifiers (SAFI)
Parameters" registry).
All other recommendations of
[draft-ietf-idr-segment-routing-te-policy] section SR Policy SAFI and
NLRI, should be taken into account for P2MP policy.
3.1.1. P2MP Policy Route
+-----------------------------------+
~ Root-ID ~ 4 or 16 octets (ipv4/ipv6)
+-----------------------------------+
| Tree-ID | 4 octets
+-----------------------------------+
| Distinguisher | 4 octets
+-----------------------------------+
o Root-ID: IPv4/IPv6 address of the head-end (root) of the p2mp tree
o Tree-ID: a unique 4 octets identifier of the p2mp tree on the
head- end (root)router.
o Distinguisher: 4-octet value uniquely identifying the policy in
the context of <Tree-ID, Originating Router's IP> tuple. The
distinguisher has no semantic value and is solely used by the SR
P2MP Policy originator to make unique (from an NLRI perspective)
multiple occurrences of the same SR P2MP Policy.
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3.1.2. Non-shared Tree Replication segment Route
A non-shared tree is used when the label field of the PMSI Tunnel
Attribute (PTA) is set to 0 as per [draft-parekh-bess-mvpn-sr-p2mp].
In short this route type is used when there is no upstream assigned
label in the PTA and aggregate of MVPNs into one P-Tunnel is not
desired.
+-----------------------------------+
| Root-ID | 4 or 16 octets (ipv4/ipv6)
+-----------------------------------+
| Tree-ID | 4 octets
+-----------------------------------+
| path-instance-ID| reserved | 2 octets
+-----------------------------------+
o Root-ID: IPv4/IPv6 address of the head-end (root) of the p2mp tree
o Tree-ID: a unique 4 octets identifier of the p2mp tree on the
head- end (Root)router
o path-instance-id, identifies the path-instance with in the p2mp-
policy. Each candidate path can have one, two or more path-
instance. Path-instance is used for global optimization of the
candidate path via make before break procedures.
3.1.3. Shared Tree Replication Segment Route
A shared tree is used when the label field of the PTA is NOT set to
Zero. This route type is used when there is an upstream assigned
label in the PTA and aggregate of MVPNs into one P-Tunnel is desired.
+-----------------------------------+
| replication-instance | 4 octets
+-----------------------------------+
o replication-instance: is a unique identifier of the replication
segment on a specific node. Each node can assign its own
replication- id for a replication segment.
3.2. Tunnel Encapsulation Attribute
The content of this new NLRI is encoded in the tunnel Encapsulation
Attribute originally defined in [ietf-idr-tunnel-encaps] using two
new Tunnel-Type TLV (codepoint is TBD, assigned by IANA from the "BGP
Tunnel Encapsulation Attribute Tunnel Types" registry) one for P2MP
Policy and another for Replication segment.
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3.2.1. SR P2MP policy encoding
SR P2MP Policy SAFI NLRI: <route-type p2mp-policy>
Attributes:
Tunnel Encaps Attribute (23)
Tunnel Type: (TBD, P2MP-Policy)
Preference
Policy Name
leaf-list (optional)
remote-end point
remote-end point
...
path-instance
active-instance-id
instance-id
instance-id
...
o SR P2MP-POLICY NLRI and P2MP Policy route type.
o Tunnel Encapsulation Attribute is defined in
[ietf-idr-tunnel-encaps]
o Tunnel-Type is set to P2MP-Policy Tunnel-Type TBD (assigned by
IANA from the "BGP Tunnel Encapsulation Attribute Tunnel Types"
registry).
o Preference, leaf-list, remote-end point, Policy Name, path-
instance, instance are defined in this document.
o Additional sub-TLVs may be defined in the future.
3.2.2. replication segment encoding
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replication segment SAFI NLRI: <route-type non-sahred/shared
tree replication-segment>
Attributes:
Tunnel Encaps Attribute (23)
Tunnel Type: (TBD Replication-Segment)
replication-sid (equivalent to binding Sid)
downstream-nodes
segment-list
segment
segment
...
segment-list
segment
segment
...
...
o SR P2MP-POLICY NLRI and non-shared tree Replication segment route
type or shared tree Replication segment route type.
o Tunnel Encapsulation Attribute is defined in
[ietf-idr-tunnel-encaps].
o Tunnel-Type is set to Replication Segment Tunnel Type, TBD
(assigned by IANA from the "BGP Tunnel Encapsulation Attribute
Tunnel Types" registry).
o tree-identifier, replication-sid (binding sid), down-stream-nodes,
segemtn-list and segment-list are defined in this document.
o Additional sub-TLVs may be defined in the future.
3.3. P2MP Policy Sub-TLVs
EACH P2MP policy NLRI represents a candidate path for a P2MP policy.
A P2MP policy can have multiple candidate paths and would need
multiple P2MP policy NRLI to download all the candidate paths.
3.3.1. preference Sub-TLV
As defined in preference Sub-TLV section in
[draft-ietf-idr-segment-routing-te-policy]
3.3.2. leaf-list Sub-TLV
The leaf list sub-tlv identifies a set of leaves for the tree. Each
leaf is a remote endpoint as defined in [ietf-idr-tunnel-encaps] The
leaf-list sub-tlv is optional. The PCE can choose to download the
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leaf list every time it is configured or learns a new leaf. If the
PCE chooses to download this optional sub-tlv it should download the
entire set of the end-points every time the endpoint list has been
modified. The leaf list has informational value but is optional
since it is not required for the root to operate. However, it must
be noted that in some cases the end-points list can become very large
with 100s of leaves.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// sub-TLVs //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: TBD
o Length: the total length (not including the Type and Length
fields) of the sub-TLVs encoded within the leaf-list sub-TLV.
o RESERVED: 1 octet of reserved bits. SHOULD be unset on
transmission and MUST be ignored on receipt.
o sub-TLVs: One or more remote endpoint sub-TLVs. Note the remote
endpoint object is defined in [ietf-idr-tunnel-encaps]
3.3.3. path-instance Sub-TLV
The path instance sub-tlv contains a set of instance-ids (P2MP LSPs).
These LSPs can be used for MBB procedure under a candidate path.
Each LSP Instance-id has a unique id (4 octets) with in the root and
the P2MP policy. The PCE SHOULD always download all instance-ids to
the node.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Sub-TLVs //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: TBD
o Length: the total length (not including the Type and Length
fields) of the sub-TLVs encoded within the Segment List sub-TLV.
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o RESERVED: 1 octet of reserved bits. SHOULD be unset on
transmission and MUST be ignored on receipt
o sub-TLVs: * active instance-id * one or more instance-id
3.3.3.1. active instance-id Sub-TLV
An instance-id is equivalent to a P2MP LSP. The instance-id is
unique in context of the <root node,p2mp policy> in other word is
unique per <root node,tree-id>. The Active instance-id is used to
identify the P2MP LSP which should be active amongst the collection
of LSPs.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| active instance-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: TBD.
o Length: the total length (not including the Type and Length
fields) of the sub-TLVs encoded within the Segment List sub-TLV.
o RESERVED: 1 octet of reserved bits. SHOULD be unset on
transmission and MUST be ignored on receipt.
o active instant-id: The identifier of the active instance-id
3.3.3.2. instance-id Sub-TLV
An instance-id is equivalent to a P2MP LSP. The instance-id is
unique in context of the <root node, p2mp policy> in other word is
unique per <root node,tree-id>
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| instance-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: TBD
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o Length: the total length (not including the Type and Length
fields) of the sub-TLVs encoded within the Segment List sub-TLV.
o RESERVED: 1 octet of reserved bits. SHOULD be unset on
transmission and MUST be ignored on receipt.
o instan-id: a 32 bit unique identifier. The instance-id is unique
with in the context of the <root node, p2mp policy>
3.4. replication segment Sub-TLVs
3.4.1. Replication SID (Binding SID)
The Replication SID is form of a Binding SID as it is defined in
[draft-ietf-idr-segment-routing-te-policy]. The definition of
replication sid with in P2MP Policy is defined in
[draft-ietf-spring-sr-replication-segment]. On the transit and leaf
node the replication SID can be used to identify the replication
segment and the forwarding information at the node. How ever on the
head-end node (Root), the replication segment acts as a Binding SID
to direct the traffic into the P2MP Tree. It should be noted that
two replication SIDs can be directly connected or connected via a SR
binding SID or node/adjacency SID.
As it was mentioned earlier the sr-te-policy binding sid sub-tlv is
used for replication sid. This draft defines a new flag for
replication sid at transit and leaf node
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|S|I|R| |
+-+-+-+-+-+-+-+-+
R-FLAG: is Replication SID. Replication SID can be used to define
the forwarding information of the transit or leaf nodes.
3.4.2. down stream nodes Sub-TLV
The down-stream nodes sub-tlv is the list of down stream nodes for
this replication segment. Two replication segments can be directly
connected or they can be connected via a sr segment-list. As such
the down stream nodes sub-tlv is a list of segment-lists. Each
segment- list connects two replication segments via a replication sid
or a segment list.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// sub-TLVs //
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
o Type: TBD.
o Length: the total length (not including the Type and Length
fields) of the sub-TLVs encoded within the down-stream nodes sub-
TLV.
o RESERVED: 1 octet of reserved bits. SHOULD be unset on
transmission and MUST be ignored on receipt. o
o sub-TLVs: One or more segment list sub-TLVs.
3.4.3. segment list Sub-TLV
The segment list Sub-TLV is defined in
[ietf-spring-segment-routing-policy]. It should be noted that P2MP
policy the optional weight Sub-TLV is not used and can optionally be
set to 1. The segment-list Sub-TLV contains zero or more segment
Sub-TLVs.
3.4.4. segment Sub-TLV
The segment sub-Tlv is identified in
[draft-ietf-idr-segment-routing-te-policy]. As it was mentioned
before two replication segments can be connected directly to each
other or via a segment list. If they are connected directly to each
other then the segment list can be constructed via:
o If the replication segment is steered via IPv4 or IPv6 nexthops or
interface then the segment type E or G can be used with the new R
flag set.
o If the replication segment is steered via a SR Unicast node or
adjacency SID then segment type A can be used with the new R flag
set. Unicast SR segment types can also be configured for
steering.
If they are connected via SR domain then the segment list can contain
multiple different types of SIDs, such as Node, Adjacency or Binding
SIDe. In this case the replication sid is at the bottom of the stack
and of type A with the R flag set. The SR node/adjacency or binding
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sids steer the packet through a SR domain until it reaches another
replication segment. where the bottom of the stack replication sid
identifies the forwarding information on that replication segment.
A replication segment can use the same type of segment types defined
in [draft-ietf-idr-segment-routing-te-policy]. To identify a
replication segment explicitly a new flag is defined.
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|V|A|R| |
+-+-+-+-+-+-+-+-+
Where R-Flag is set for a segment Sub-TLV that identifies a
Replication Segment. It should be noted that in a segment list only
the last segment can have the R flag set. Multiple replication
segments can not be stacked on top of each other. That said there
can be special cases for Link Protection where a bypass tunnel is
build via a shared replication segment. As an example when the PCE
downloads a bypass tunnel for link protection that is only
constructed via shared replication segments to protect a group of
non-shared replication segments.
4. P2MP Policy Operation
Inline with [draft-ietf-idr-segment-routing-te-policy] the consumer
of an P2MP Policy is not the BGP process. The BGP process is used
for distributing the P2MP policy NLRI and its route-types but its
installation and use is outside the scope of BGP. The detail for
P2MP Policy can be found in [draft-ietf-pim-sr-p2mp-policy]
4.1. Configuration and advertisement of P2MP Policies
The controller usually is connected to the receivers via a route
reflector. As such one or more route-target SHOULD be attached to
the advertisement of P2MP Policy NLRI and its route-type. Each route
target identifies one head-end (root nodes) for P2MP Policy route or
one or more head-end, transit and leaf nodes for the Non- Shared/
Shared Tree Replication Segment route, for the advertised P2MP
Policy.
If no route-target is attached to the NLRI, then it is assumed that
the originator sends the P2MP Policy update directly to the intended
receiver. In such case, the NO_ADVERTISE community MUST be attached
to the P2MP Policy update.
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4.2. Reception of an P2MP Policy NLRI
When a BGP speaker receives an P2MP Policy NLRI the following rules
apply:
o The P2MP Policy update MUST have either the NO_ADVERTISE community
or at least one route-target extended community in IPv4-address
format. If a router supporting this document receives an P2MP
Policy update with no route-target extended communities and no
NO_ADVERTISE community, the update MUST NOT be processed.
Furthermore, it SHOULD be considered to be malformed, and the
"treat-as-withdraw" strategy of [RFC7606] is applied.
o If one or more route-targets are present, then at least one route-
target MUST match one of the BGP Identifiers of the receiver in
order for the update to be considered usable. The BGP Identifier
is defined in [RFC4271] as a 4 octet IPv4 address. Therefore the
route- target extended community MUST be of the same format.
o If one or more route-targets are present and no one matches any of
the local BGP Identifiers, then, while the P2MP Policy NLRI is
acceptable, it is not usable on the receiver node.
4.3. Global Optimization for P2MP LSPs
When a P2MP LSP needs to be optimized for any reason (i.e. it is
taking on an FRR Path or new routers are added to the network) a
global optimization is possible. Note that optimization works per
candidate path. Each candidate path is capable of global
optimization. To do so each candidate path contains two or more
path- instances. Each path instance is a P2MP LSP, each P2MP LSP is
identified via a path-instance-id (equivalent to an lsp-id
[RFC3209]). After calculating an optimized P2MP LSP path the PCE
will program the candidate path with a 2nd path instance and its set
of replication segments for this path-instance on the root, transit
and leaf nodes. After the optimized LSP replication segments are
downloaded a MBB procedure is performed and the previous instance of
the path instance is deleted and removed from head-end node and its
corresponding replication segments from head-end, transit and leaves.
5. IANA Consideration
o A new SAFI is defined: the SR P2MP Policy SAFI, (Codepoint tbd
assigned by IANA)
o 3 new Route type field defines the encoding of the rest of the
P2MP- POLICY SAFI
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* P2MP Policy Route
* Non-Shared Replication Segment
* Shared Replication Segment
o Two new Tunnel type to be assigned by IANA
6. Security Considerations
TBD
7. Acknowledgments
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
8.2. Informative References
[draft-ietf-idr-segment-routing-te-policy]
.
[draft-ietf-pim-sr-p2mp-policy]
"D. Yoyer, C. Filsfils, R.Prekh, H.bidgoli, Z. Zhang,
"draft-ietf-pim-sr-p2mp-policy"", October 2019.
[draft-ietf-spring-segment-routing-policy]
.
[draft-ietf-spring-sr-replication-segment]
"D. Yoyer, C. Filsfils, R.Prekh, H.bidgoli, Z. Zhang,
"draft-ietf-pim-sr-p2mp-policy "", July 2020.
[draft-parekh-bess-mvpn-sr-p2mp]
.
[ietf-idr-tunnel-encaps]
.
[ietf-spring-segment-routing-policy]
.
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[RFC4271] .
[RFC4760] .
[RFC6513] .
[RFC7606] .
Authors' Addresses
Hooman Bidgoli (editor)
Nokia
Ottawa
Canada
Email: hooman.bidgoli@nokia.com
Daniel Voyer
Bell Canada
Montreal
Canada
Email: daniel.yover@bell.ca
Andrew Stone
Nokia
Ottawa
Canada
Email: andrew.stone@nokia.com
Rishabh Parekh
Cisco System
San Jose
USA
Email: riparekh@cisco.com
Serge Krier
Cisco System, Inc.
Email: sekrier@cisco.com
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Arvind Venkateswaran
Cisco System, Inc.
Ottawa
Canada
Email: arvvenka@cisco.com
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