Any advantage of announcing IPv6/64s Or purely misconfiguration?

Justin M. Streiner streiner at
Mon Jul 9 15:12:16 UTC 2012

On Mon, 9 Jul 2012, Anurag Bhatia wrote:

> I was just looking around and say a major Indian provider Sify (AS9583) is
> announcing /64s via BGP along with main /32 which is their allocation from
> Is it simply a misconfiguration or there is some use of announcing /64s
> along with main /32?

Most of the major carriers I've seen appear to have settled on /48 as the 
smallest IPv6 prefix they will accept, much like /24 is the smallest IPv4
prefix that most providers will accept.  Anything smaller runs the risk of 
mixed degrees of acceptance.  As long as the /64 is part of a larger 
parent block, there shouldn't be any total loss of connectivity, however 
the routing to one of those /64 sites could be sub-optimal.

Advertising /64s into the global routing table is bad mojo.


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