/8 end user assignment?

Fri Aug 5 13:55:32 UTC 2005

On 5 Aug 2005, at 07:54, Sabri Berisha wrote:

>
> On Fri, Aug 05, 2005 at 04:10:46AM -0700, Bill Woodcock wrote:
>>
>>       On Fri, 5 Aug 2005, Sabri Berisha wrote:
>>> With the use of anycast DNS servers on the internet, TCP is no 
>>> longer an
>>> option for DNS.
>>
>> Bzzzt.  Try again.
>
>
> 			/--[cabernet]--[merlot]--[riesling]--[server 1]
> [end-host] ----- [shiraz]		  |
> 			\--[sangria]]--[chardonnay]--[bordeaux]--[server 2]

It is of course possible to construct networks through which TCP 
behaves very poorly with anycasted services. This does not mean that 
TCP is fundamentally incompatible with anycast.

There are plenty of examples of people anycasting services which 
involve long-held TCP sessions (like FTP servers, and HTTP server 
serving large media files). Naturally not all networks and not all node 
placement decisions will work for these kinds of services, but it is 
certainly possible to use anycast to great effect with very high 
service quality.

See draft-grow-ietf-anycast-01 for more commentary.

Joe