Cogent IPV6 connectivity to

Clinton Work clinton at
Mon Nov 4 15:41:28 UTC 2013

I should have stated that I tried icmpv6, UDP, and TCP traceroute with
the same results.  Looks like Cogent is not returning TTL expired IPV6
packets within their core.  I can only guess that this is a result of
using 6PE and propagating the IPV6 TTL into MPLS.  


On Sun, Nov 3, 2013, at 09:47 PM, Joe Abley wrote:
> "Traceroute packets" is extremely vague. As a general rule, if you
> want to discover a complete path between endpoints that are expected
> to communicate using 80/tcp, trace the route using 80/tcp.
> (Not that it's ever expected to see protocol-specific drops in a core
> or across a transit or peering edge.)

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