This post to the NANOG list in the hope that an interested engineer from either Qwest or GBLX will act on the problem I have observed. I've identified a packet loss problem (10-15%) between Qwest and Global Crossing. From one end (HP), the partial traceroute is: traceroute to 68.85.190.221 (68.85.190.221), 30 hops max, 40 byte packets 1 lpagwb01-vlan151-phy.hpl.hp.com (192.6.19.2) 0.622 ms 0.378 ms 0.315 ms 2 * * * 3 * * * 4 65.115.64.25 (65.115.64.25) 1.380 ms 1.297 ms 1.233 ms 5 205.171.14.150 (205.171.14.150) 1.377 ms 1.385 ms 1.277 ms 6 67.14.34.14 (67.14.34.14) 1.955 ms 2.046 ms 1.962 ms 7 205.171.233.18 (205.171.233.18) 2.204 ms 2.204 ms 2.076 ms 8 63.146.26.42 (63.146.26.42) 5.937 ms 4.253 ms 4.574 ms 9 * COMCAST-IP-SERVICES-LLC.TenGigabitEthernet1-3.ar2.snv2.gblx.net (64.211.1.214) 21.942 ms 21.670 ms There's no packet loss until the `gblx.net' (64.211.1.214) is pinged. Coming from the other end (Comcast), the partial traceroute is: Tracing route to gundega.hpl.hp.com [192.6.19.190] over a maximum of 30 hops: 1 * * * Request timed out. 2 9 ms 7 ms 7 ms 68.85.190.221 3 8 ms 6 ms 6 ms 68.87.226.66 4 7 ms 6 ms 7 ms te-9-1-ur06.sanjose.ca.sfba.comcast.net [68.87.192.54] 5 9 ms 9 ms 11 ms te-0-3-0-4-ar01.oakland.ca.sfba.comcast.net [68.87.226.229] 6 11 ms 11 ms 11 ms pos-0-4-0-0-cr01.sacramento.ca.ibone.comcast.net [68.86.90.141] 7 13 ms 12 ms 13 ms pos-0-8-0-0-cr01.sanjose.ca.ibone.comcast.net [68.86.85.78] 8 14 ms 12 ms 12 ms TenGigabitEthernet3-1.ar1.snv2.gblx.net [64.214.174.109] 9 41 ms * 38 ms sjp-brdr-02.inet.qwest.net [63.146.26.41] Pinging from this direction, there no packet loss until the first Qwest router (63.146.26.41) is pinged. So it seems clear that the problem is between Qwest and Global Crossing. ------ Andris