HP 6125G HP 6125G & 6125G/XG Blade Switches IP Multicast Configuration - Page 197

Configuring MBGP, MBGP overview, Protocols and standards, MBGP configuration task list

Page 197 highlights

Configuring MBGP This chapter covers configuration tasks related to multiprotocol BGP for IP multicast only. For more information about BGP, see Layer 3-IP Routing Configuration Guide. The term "router" in this chapter refers to both routers and Layer 3 switches. MBGP overview BGP-4 can carry routing information for IPv4 only. IETF defined Multiprotocol Border Gateway Protocol (MP-BGP) to extend BGP-4 so that BGP can carry routing information for multiple network-layer protocols. For a network, the topology for multicast might be different from that for unicast. To distinguish them, the MP-BGP enables BGP to carry the unicast Network Layer Reachability Information (NLRI) and multicast NLRI separately. The multicast NLRI performs reverse path forwarding (RPF) exclusively. In this way, route selection for a destination through the unicast routing table and through the multicast routing table have different results, ensuring consistent unicast forwarding and normal multicast between domains. For more information about RPF, see "Configuring multicast routing and forwarding." MP-BGP is defined in RFC 2858 (Multiprotocol Extensions for BGP-4). The application of MP-BGP on multicast is called Multicast BGP (MBGP). Protocols and standards • RFC 2858, Multiprotocol Extensions for BGP-4 • RFC 3392, Capabilities Advertisement with BGP-4 • draft-ietf-idmr-bgp-mcast-attr-00, BGP Attributes for Multicast Tree Construction • RFC 4271, A Border Gateway Protocol 4 (BGP-4) • RFC 5291, Outbound Route Filtering Capability for BGP-4 • RFC 5292, Address-Prefix-Based Outbound Route Filter for BGP-4 MBGP configuration task list Task Remarks Configuring basic MBGP functions Required Configuring MBGP route redistribution Required Configuring default route redistribution into MBGP Optional Controlling route advertisement and reception Configuring MBGP route summarization Optional Advertising a default route to an IPv4 MBGP peer or peer group Optional Configuring outbound MBGP route filtering Optional Configuring inbound MBGP route filtering Optional Configuring MBGP route dampening Optional 186

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186
Configuring MBGP
This chapter covers configuration tasks related to multiprotocol BGP for IP multicast only. For more
information about BGP, see
Layer 3—IP Routing Configuration Guide
.
The term "router" in this chapter refers to both routers and Layer 3 switches.
MBGP overview
BGP-4 can carry routing information for IPv4 only. IETF defined Multiprotocol Border Gateway Protocol
(MP-BGP) to extend BGP-4 so that BGP can carry routing information for multiple network-layer protocols.
For a network, the topology for multicast might be different from that for unicast. To distinguish them, the
MP-BGP enables BGP to carry the unicast Network Layer Reachability Information (NLRI) and multicast
NLRI separately. The multicast NLRI performs reverse path forwarding (RPF) exclusively. In this way, route
selection for a destination through the unicast routing table and through the multicast routing table have
different results, ensuring consistent unicast forwarding and normal multicast between domains. For
more information about RPF, see "
Configuring multicast routing and forwarding
."
MP-BGP is defined in RFC 2858 (Multiprotocol Extensions for BGP-4). The application of MP-BGP on
multicast is called Multicast BGP (MBGP).
Protocols and standards
RFC 2858,
Multiprotocol Extensions for BGP-4
RFC 3392,
Capabilities Advertisement with BGP-4
draft-ietf-idmr-bgp-mcast-attr-00,
BGP Attributes for Multicast Tree Construction
RFC 4271,
A Border Gateway Protocol 4 (BGP-4)
RFC 5291,
Outbound Route Filtering Capability for BGP-4
RFC 5292,
Address-Prefix-Based Outbound Route Filter for BGP-4
MBGP configuration task list
Task
Remarks
Configuring basic MBGP functions
Required
Controlling route
advertisement and
reception
Configuring MBGP route redistribution
Required
Configuring default route redistribution into MBGP
Optional
Configuring MBGP route summarization
Optional
Advertising a default route to an IPv4 MBGP peer or peer group
Optional
Configuring outbound MBGP route filtering
Optional
Configuring inbound MBGP route filtering
Optional
Configuring MBGP route dampening
Optional