IPv4 Anycast?

Wed Apr 22 20:01:48 UTC 2009

Jack Bates wrote:
> Zhenkai Zhu wrote:
>> Then there is basically no inter-As anycast besides the anycast 
>> prefix for DNS root, since I only noticed like 8 prefixes that are 
>> announced by more than 3 ASes..
>>
>
> I presume you are using route-views or some such to get a larger 
> picture of the BGP geography? 

Yes.

> I believe that many anycasts utilize the same ASN for their anycasted 
> address space. I would expect that a few of them have an ASN 
> specifically for their anycasted space.
>
>  Given that the networks are duplicates, there's no requirement that 
> one part of the AS needs to receive routes from the other part of the 
> AS. For management and such of the devices, I presume there are 
> separate netblocks advertised with a different ASN (possibly even 
> statically assigned by a hosting network).

I just want to make sure if I understand correctly. You mean that the 
anycasted address space can be announced in different places yet with 
the same origin AS?

Zhenkai

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> Jack
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