Possible explanations for a large hop in latency
John T. Yocum
john at fluidhosting.com
Thu Jun 26 19:03:46 CDT 2008
When I asked ATT about the sudden latency jump I see in traceroutes,
they told me it was due to how their MPLS network is setup.
Frank Bulk wrote:
> Our upstream provider has a connection to AT&T (18.104.22.168) where I
> relatively consistently measure with a RTT of 15 msec, but the next hop
> (22.214.171.124) comes in with a RTT of 85 msec. Unless AT&T is sending that
> traffic over a cable modem or to Europe and back, I can't see a reason why
> there is a consistent ~70 msec jump in RTT. Hops farther along the route
> are just a few msec more each hop, so it doesn't appear that 126.96.36.199
> has some kind of ICMP rate-limiting.
> Is this a real performance issue, or is there some logical explanation?
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