icmp performance vs. traceroute/tcptraceroute, ssh, ipsec

Joe Shen joe_hznm at
Mon May 7 07:16:41 UTC 2007

I agree with Dale. The problem should be with e2e TCP

Maybe there is misconfigured firewall which block SYN
or ACK packet. Or, packet larger than 128B is dropped.

As you can find in your data, ping and traceroute show
different response speed. 

Maybe you could try layer4 traceroute, and try packet
size bigger than 1000Byte. It will show you where the
problem may exist. 


ICMP or traceroute usually use small packet. 

--- Joe Maimon <jmaimon at> wrote:

> Lincoln Dale wrote:
> >>traceroute/tcptraceroute show packet loss and MUCH
> higher rtt than the
> >>corresponding direct pings on the reported hop
> entries.
> >>
> >>Is this some sort of massaging or plain just
> "faking it"? Or is such
> >>things merely net-urban myth?
> > 
> > 
> > the vast majority of routers on the internet
> respond very differently to
> > traffic 'directed at them' as opposed to traffic
> 'routed through them'.
> Thanks for your reply.
> I did include icmp echo directly to each hop as a
> comparison.

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