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Re: level3.net in Chicago - high packet loss?!?

  • From: Network Fortius
  • Date: Tue Sep 06 10:26:22 2005
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And how exactly would you interpret the number returned by net_loss (int), in a column called "LOSS", in reference to reachability of a "hop" between two end points:

int net_loss(int at)
{
if ((host[at].xmit - host[at].transit) == 0)
return 0;
/* times extra 1000 */
return 1000*(100 - (100.0 * host[at].returned / (host[at].xmit - host[at].transit)) );
} ?

Thanks,
Stef
Network Fortius, LLC


On Sep 6, 2005, at 7:45 AM, Robert E.Seastrom wrote:

Network Fortius <[email protected]> writes:



Anybody having any idea why such a high packet loss on lever3's
network, in Chicago?


End-user misinterpreting output from MTR.  This network does not
appear to have any packet loss end-to-end.

                                        ---Rob
Stef:~ scm$ mtr -r www.yahoo.com
...
tbr1-p010802.cgcil.ip.att.net 0% 16 16 15.12
24.21 49.26
ggr2-p310.cgcil.ip.att.net 0% 16 16 13.18
42.66 118.99
so-1-1-0.edge1.chicago1.level3.net 0% 16 16 14.48
35.84 126.48
so-2-1-0.bbr1.chicago1.level3.net 63% 6 16 14.44
43.74 79.97
^^^^^^^
as-1-0.bbr2.sanjose1.level3.net 0% 16 16 61.95
80.64 176.01
ge-10-2.ipcolo3.sanjose1.level3.net 0% 16 16 63.37
95.61 148.46
unknown.level3.net 0% 16 16 63.34
86.46 168.62
unknown-66-218-82-217.yahoo.com 0% 16 16 62.09
88.91 127.58
p4.www.scd.yahoo.com 0% 16 16 64.51
89.96 183.79

TIA,
Stef
Network Fortius, LLC