BCP for multisite multihoming

[Leo Vegoda]

On 21 May 2007, at 3:04pm, Kevin Day wrote:

>
> I ask this partly rhetorically(I think I already know the answer)  
> and partly to see which alternative everyone else would use in this  
> situation.
>
> Assume the following:
>
> 1) A company has four branch offices(POPs) around the world, New  
> York, London, Tokyo and Sydney.
> 2) This company requires IP addresses for internal use, customer  
> use, etc.

At the point you say that they will be assigning address space to a  
customer they become an ISP, I suppose.

> 3) Each POP must be multihomed, with connections to two or more  
> transit providers.
> 4) Multihoming must support load balancing in both directions.
> 5) Each POP has a unique set of transit providers, there isn't one  
> transit provider that has service at all locations.
> 6) Transit providers come and go, PA space isn't acceptable.
> 7) There is no connectivity between each POP at all, everything  
> between nodes goes over the internet.

This seem to be four separate ISPs, in four separate continents that  
just happen to be owned by a single organisation and possibly share a  
brand.

[...]

> 4) Obtain multiple /32s, announce one from each POP.
>
> Probably not possible - The bar is pretty high to receive a second / 
> 32, most companies will never reach the utilization percentage to  
> receive a second, let alone one per POP.

Presumably this company is incorporated in each country in which it  
has a PoP. It is effectively four companies with a common owner. As  
such, I think #4 is the right answer and I don't think it should be  
too difficult to get the address space.

[...]

> * If these four offices were multiple companies instead of owned by  
> the same, they'd have no problem obtaining space and announcing  
> their own space at each POP. It would also equal the same number of  
> routes in the table as if the one company had just deaggregated.  
> Things are being complicated because they're owned by the same  
> legal entity. One legal entity doesn't necessarily equal one unique  
> network though.

Bingo!

Regards,

-- 
Leo Vegoda
IANA Numbers Liaison