Benefits of MBGP

[y.manirko]

Hello,

I need to enable multicast between two PIM-SM multicast domains. Currently these domains exchange only unicast traffic via two pairs EBGP piers. Both pairs advertise the same sets of prefixes to each other. I am going to enable MSDP peering between RP in Domain1 and RP in Domain2. Additionally I am going to enable PIM-SM on all the BGP peering interfaces. I do not care which path multicast traffic from Domain1 will flow to Domain2 and vice versa. It can be ether first pair of EBGP piers, or second pair. Why would I want to configure MBGP in this case? If I do not want to control and redistribute multicast traffic between BGP paths, how MBGP can be beneficial for me?

Thank you,

Yuri

[sbilgi]

MBGP is an enhanced BGP that carries IP multicast routes.

MBGP is useful when you want a link dedicated to multicast traffic.

In this way you can limit which resources are used for which traffic.

For eg:.if you want all multicast traffic exchanged at one network access point (NAP), this is very useful.

MBGP allows you to have a unicast routing topology different from a multicast routing topology.

Thus, you have more control over your network and resources.

Coming to your scenario, since you do not want a dedicated path for the multicast traffic, it is not really needed.

But, the following are the additional benefits provided by MBGP.

*A network can support incongruent unicast and multicast topologies.

*A network can support congruent unicast and multicast topologies that have different policies

*A network can carry routing information for multiple network layer protocol address families.

*A network that is backward compatiblerouters that support the Multiprotocol extensions can interoperate with routers that do not support the extensions.

*All of the routing policy capabilities of BGP can be applied to MBGP.

*All of the BGP commands can be used with MBGP..

So depending on your requirements and comparing it with the benefits, you can decide upon whether to use MBGP.