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BGP Bandwidth

My client has an idea of connecting multiple ISP's for internet access. The ISP has claimed that in order to run BGP between each of the ISP and the local routers he needs minimum of 512K link.

Is there any way ( by configuring BGP parameters ) to manage with 64K links ?


Re: BGP Bandwidth

No problem running BGP on a 9.6Kbps line if all you want is a default route from your ISP (to detect if the link is OK) and advertise a couple of routes to the ISPs (so they can detect if you are up). Just keep in mind that there is what is technically feasible and there is what your ISP is willing to sell you. The former usually only influences the latter negatively.

Good luck and have fun!

VIncent C Jones

Community Member

Re: BGP Bandwidth


I have another question. Is it necessary to terminate two ISP links at TWO local routers to prevent unwanted traffic be passing through local router ?

Community Member

Re: BGP Bandwidth


In 1 router you can do what you want.



Re: BGP Bandwidth

In regards to transiting traffic... No--this is a matter of filtering what you are advertising, rather than a matter of how many routers you have connected. Use an as-path access-list to permit only prefixes with an as path of ^$, and this should take care of your transiting worries. You can also use a prefix list to limit what you advertise to prefixes you are originating.

BGP will run fine over a 64k link, as long as your traffic doesn't overcome it.


Community Member

Re: BGP Bandwidth

Is it a must to have "Provider Indipendant IP's" to run BGP with multiple ISP's ? Can I also use private AS number for my installation in this scenario ?

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