Strange practices?

Joe Provo nanog-post at
Mon Jun 7 21:00:12 UTC 2010

On Mon, Jun 07, 2010 at 03:50:25PM -0500, Dale Cornman wrote:
> Has anyone ever heard of a multi-homed enterprise not running bgp with
> either of 2 providers, but instead, each provider statically routes a block
> to their common customer and also each originates this block in BGP?   

Yes; tends to happen for clueless endpoints or providers who don't
expressly require BGP for multihoming.`

> One
> of the ISP's in this case owns the block and has even provided a letter of
> authorization to the other, allowing them to announce it in BGP as well.
>   I had personally never heard of this and am curious if this is a common
> practice as well as if this would potentially create any problems by 2
> Autonomous Systems both originating the same prefix.

MOAS prefixes are common in some content-origination applications, but 
since you never know what the rest of the universe is going to do in 
their routing & forwarding decisions, is really isn't generally applicable.

             RSUC / GweepNet / Spunk / FnB / Usenix / SAGE

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