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Will running BGP be beneficial to me?

I need some advice on how to utilize my two serial interfaces on my outside router that is positioned in front of my firewall more efficiently. Currently serial0/0 is connected to ISP-A and serial1/0 is connected to ISP-B. Serial0/0 is my default route handling Internet requests and serial1/0 is used for business partner VPN tunnels.

My WAN equipment is made up of this above outside router, PIX firewall, then my inside router.

outside router terminates differing ISP vendor supplied circuits

PIX handles IPSec

inside router handles Inter-Business GRE interfaces.

Considering the above design, if ISP-A was to fail, my users would not be able to access the internet. Likewise, if ISP-B was to fail, I would lose my VPN connections to my branch offices.

It would be great if I can use something like HSRP on my outside routers but these are differing subnets and serial interfaces. I can?t multi-link because these are two different service providers. I imagine that I can attach a second Ethernet interface from my PIX to my outside router and configure parallel VPN/GRE instances.

The reason for my inquiry:

On my outside router, I?m contemplating running BGP. Would this prove beneficial to me and how would I overcome the limitation or issues that might be presented with the default route statement on my outside router, or with BGP, will I need a default route?

Best Regards


  • WAN Routing and Switching

Re: Will running BGP be beneficial to me?


You could benefit from running BGP, but here's the problem (maybe). To run BGP you need a couple of things; an AS and an address space. Those are the two hardest to get. If you can justify and receive them, you're good to go. Here's a link to ARIN's requirements.

and a pretty flow chart of what needs to be done-

HTH and please rate.

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