Advertising BGP-4 from two islands

William Herrin herrin-nanog at
Sun Sep 13 06:22:32 UTC 2009

On Sat, Sep 12, 2009 at 9:35 PM, Francois Menard<francois at> wrote:
> I have an opportunity to launch services in a remote marke, where I cannot
> extend my backbone to.
> However, this market is big enough that I can afford to put a Cisco 7201
> over there and peer in BGP-4.
> Do you have any advice as to what may happen if I advertise different blocks
> from the same AS number, from two different locations, one of which I do not
> have my own transport facilities to...

This probably qualifies as a "unique routing policy" under ARIN NRPM
section 5. That allows you to get another AS number.

You could also get a small block of staticly-routed IPs from your ISPs
in each location and use them to anchor a VPN (e.g. a GRE tunnel).
That'd have the effect of extending your backbone.

Bill Herrin

William D. Herrin ................ herrin at  bill at
3005 Crane Dr. ...................... Web: <>
Falls Church, VA 22042-3004

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