BGP for P2MP-LSP
Satoru Matsushimasatoru@ft.solteria.net

Copyright © 2004 Satoru Matsushima. All rights reserved.

Motivation
Need the fast recovery mechanism forthe Multicast traffic
Need the Traffic-Engineering feature for
the Multicast traffic
Need the Inter-Domain Multicast
environments

Copyright © 2004 Satoru Matsushima. All rights reserved.

Problems
P2MP TE-LSP has already proposed
P2MP TE-LSP use RSVP extension
IGP area configuration will restrict P2MPLSP deployment
Lack of mechanism to discover/notify the P2MP
capable node on Inter-Area/Inter-Domain

Increase a lot of path-state
We have BGP!
Copyright © 2004 Satoru Matsushima. All rights reserved.

Advantage of BGP for P2MP
Applicable for the Inter-Area/Inter-Domain
BGP messages traverse Area/Domain border
Easy and mature policy-control

BGP-LSP stitch P2MP-LSP on Branch-LSR
P2MP path-state/instance exist at Branch-LSR
Core/non-P2MP LSR doesn’t have path-state ofP2MP-LSP

Copyright © 2004 Satoru Matsushima. All rights reserved.

P2MP-LSP Overview
SenderIngress
LSR1

BranchLSR2

LSR3

BranchLSR4EgressLSR5Egress
LSR6Egress
LSR7

Receiver3
P2MP-LSPReceiver1

Receiver2

Copyright © 2004 Satoru Matsushima. All rights reserved.

P2MP InstanceBGP for P2MP LSP
Advertising P2MP-LSP=L

Ingress
LSR-a

Advertising P2MP-LSP=L
w/ brach-LSR-bBranch
LSR-bJoined P2MP-LSP=L
Upstream LSR=a

Advertising P2MP-LSP=L
w/ branch-LSR-b and c

BranchLSR-cJoined P2MP-LSP=L
Upstream LSR=b

Egress
LSR-dJoined P2MP-LSP=L
Upstream LSR=c

Copyright © 2004 Satoru Matsushima. All rights reserved.

Flood P2MP info to thenetwork
IngressLSR

BGP Update
P2MP-LSP-COMMUNITY

BranchLSR

BranchLSREgress
LSR-1

Egress
LSR-3
EgressLSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Flood P2MP capable info tothe network
IngressLSR

BGP Update

BranchLSR-aBranchLSR-b

BGP Update

P2MP-LSP-COMMUNITY

P2MP-LSP-COMMUNITY

P2MP-LSP-BRANCH-LIST=a

P2MP-LSP-BRANCH-LIST=b

Egress
LSR-1

Egress
LSR-3
EgressLSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Making the branch-node tree
IngressLSR

BGP Update
Branch
LSR-aBranch
LSR-b

P2MP-LSP-COMMUNITY
P2MP-LSP-BRANCH-LIST=a
P2MP-LSP-BRANCH-LIST=bEgress
LSR-1

Egress
LSR-3Egress
LSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Join to P2MP-LSP(1)IngressLSR

BGP Update
P2MP-LSP-COMMUNITY

Branch
LSR-aBranch
LSR-b

P2MP-IMPORTED-BRANCH=a

BGP Update
P2MP-LSP-COMMUNITY
P2MP-IMPORTED-BRANCH=b

Egress
LSR-1

Egress
LSR-3
EgressLSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Join to P2MP-LSP(2)IngressLSR
BGP Update
P2MP-LSP-COMMUNITY
P2MP-IMPORTED-BRANCH=Ingress

Branch
LSR-aBranch
LSR-b

BGP UpdateEgress
LSR-1

P2MP-LSP-COMMUNITY
P2MP-IMPORTED-BRANCH=b

Egress
LSR-3

EgressLSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Established P2MP-LSP
Ingress
LSR

BranchLSR-aBranch
LSR-bEgress
LSR-1

Egress
LSR-3
EgressLSR-2

Copyright © 2004 Satoru Matsushima. All rights reserved.

Coexisting w/ RSVP-P2MP
Scenario
Other area/domain

Intra area/domain
BGP P2MP-LSP
RSVP P2MP-LSP
Ingress
LSR

BranchLSR

BranchLSR

BorderLSR

BranchLSR

Copyright © 2004 Satoru Matsushima. All rights reserved.

Summary
BGP is applicable for P2MP-LSP
Inter-Area/Domain
Saving number of path-state

BGP P2MP-LSP can co-exist w/ P2MPTE-LSP

Copyright © 2004 Satoru Matsushima. All rights reserved.

Thank you!

Copyright © 2004 Satoru Matsushima. All rights reserved.