why would an enterprise use BGP ?

[mohammed hashim]

hi all

I understand the BGP routing protocol and how it works, and why ISPs need BGP to exchange routes.

but why would an Enterprise use BGP for their internet access ?

if it all what they need is the internet access, then they can simply forward the traffic to the ISP, and the ISP will take care of the traffic !

???

thanks,

[Joseph W. Doherty]

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Posting

Presupposing you only have one Internet connection, you're correct, you shouldn't need to use BGP with your ISP.

However, if you have multiple Interconnections, especially with different ISPs, the BGP with them can be useful.  The most common reason, is to "know" best path to same destination, between ISPs.  But BGP can also be use to dynamically pass policy information.

In fact, dynamic policy information, via the routing protocol, is one reason BGP might be used internally with a (large) Enterprise.

[Jeff Van Houten]

For an enterprise with multiple sites, many MPLS providers require the CE routers run BGP to exchange routes with the PE providers so a mesh network can be created.