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Date: Thu, 30 Jul 2015 06:52:57 +0200 (CEST)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: David Lang <david@lang.hm>
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Cc: bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] Speed tests - attribution of latency to relevant
 network hops
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On Wed, 29 Jul 2015, David Lang wrote:

> unless you measure it per hop, how are you going to attribute it to each 
> hop? and unless you have a server at that layer to talk to, how do you 
> know what the latency or bandwidth is?

Measuring latency is doable (using the same mechanism that traceroute with 
for instance max-ttl 5), but I don't know how much of this is available to 
your web application?

If you sent 5 packets with TTL 1-5 and measured the time to get back the 
ttl-expired-in-transit ICMP, you could get an indication where the latency 
increase was happening.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se