I'm setting up a tunnel to my home in the Chicagoland area, and was glad to see a Chicago PoP to connect to. To my surprise, the Chicago PoP actually demonstrated higher latency to my comcast connection than did the one in NY. A quick traceroute suggests that both connections are passing through the east cost; the Chicago PoP making a round trip before it even starts its way back to me:
-New York PoP-
traceroute to 209.51.161.14 (209.51.161.14), 30 hops max, 40 byte packets
1 * * *
2 ge-1-46-ur01.romeoville.il.chicago.comcast.net (68.85.208.161) 20.779 ms 20.838 ms 20.955 ms
3 te-8-2-ur02.romeoville.il.chicago.comcast.net (68.87.230.118) 20.467 ms 20.562 ms 20.536 ms
4 te-8-3-ar02.elmhurst.il.chicago.comcast.net (68.87.231.94) 20.125 ms 20.336 ms 20.227 ms
5 te-8-2-ar02.elmhurst.il.chicago.comcast.net (68.87.231.90) 19.743 ms 19.708 ms 19.701 ms
6 te-2-1-ar01.area4.il.chicago.comcast.net (68.87.230.121) 20.326 ms 19.359 ms 19.165 ms
7 68.86.90.49 (68.86.90.49) 20.252 ms 20.155 ms 20.060 ms
8 TenGigabitEthernet2-3.ar5.CHI1.gblx.net (64.209.88.253) 19.568 ms 19.574 ms 19.679 ms
9 HURRICANE-ELECTRIC-LLC-Ashburn.TenGigabitEthernet4-4.ar3.DCA3.gblx.net (64.214.121.170) 55.294 ms 55.776 ms 55.833 ms
10 10gigabitethernet1-2.core1.nyc4.he.net (72.52.92.85) 55.598 ms 55.550 ms 50.787 ms
11 tserv4.nyc4.ipv6.he.net (209.51.161.14) 55.266 ms 60.093 ms 60.073 ms
-Chicago PoP-
traceroute to 209.51.181.2 (209.51.181.2), 30 hops max, 40 byte packets
1 * * *
2 ge-1-46-ur01.romeoville.il.chicago.comcast.net (68.85.208.161) 17.937 ms 17.998 ms 18.137 ms
3 te-8-2-ur02.romeoville.il.chicago.comcast.net (68.87.230.118) 17.783 ms 17.658 ms 17.655 ms
4 te-8-3-ar02.elmhurst.il.chicago.comcast.net (68.87.231.94) 17.174 ms 17.155 ms 17.171 ms
5 te-8-2-ar02.elmhurst.il.chicago.comcast.net (68.87.231.90) 16.591 ms 16.951 ms 16.853 ms
6 te-2-1-ar01.area4.il.chicago.comcast.net (68.87.230.121) 19.650 ms 10.434 ms 14.892 ms
7 pos-0-13-0-0-cr01.chicago.il.ibone.comcast.net (68.86.90.53) 20.901 ms 20.990 ms 20.977 ms
8 TenGigabitEthernet2-2.ar5.CHI1.gblx.net (64.213.79.245) 20.285 ms 20.288 ms 20.267 ms
9 HURRICANE-ELECTRIC-LLC-Ashburn.TenGigabitEthernet4-4.ar3.DCA3.gblx.net (64.214.121.170) 57.170 ms 57.228 ms 57.183 ms
10 10gigabitethernet1-2.core1.nyc4.he.net (72.52.92.85) 56.880 ms 56.004 ms 51.237 ms
11 10gigabitethernet1-2.core1.chi1.he.net (72.52.92.102) 76.054 ms 72.770 ms 78.027 ms
12 tserv9.chi1.ipv6.he.net (209.51.181.2) 78.013 ms 77.941 ms 77.779 ms
Is this normal?
Hurricane peers aggressively at over 23 different exchange points globally.
Comcast peers where Comcast wants and Comcast routes how they want.
If you are a Comcast customer perhaps you could persuade them to buy transit from or peer with Hurricane in Chicago and other locations.
Could you explain how you can tell that this is an issue with the Comcast connection? (Genuine curiosity)
I just tracerouted to the Seattle, Miami, Ashburn, and Dallas PoPs from the same location, and none of them took this detour. Does this mean that out of all the locations I've tried, Chicago is the only one Comcast is not peering with? (I assume the peering takes place on the Global Crossing network, because that's where the discrepancy is. Comcast's routers appear to be staying within IL.)
Thanks
Edit: To further confuse myself, I just did a quick trace from my Verizon WAN card as well. It did not transit global crossing, nor use the comcast network, yet the trace to chicago still hits nyc4.he.net before it hits chi1.he.net, and again miami and dallas did not. :\
Comcast does not appear to peer with HE. It instead determines that the best path is through GBLX, whom HE peers with. (Actually, I believe HE buys transit from GBLX, but don't quote me on that.) They apparently don't peer with each other in Chicago, so GBLX has to send it to New York to reach HE's network.
I wouldn't really say that it is an issue with Comcast, but you would get a shorter route if Comcast peered with HE in Chicago, or even if GBLX peered with HE in Chicago.
Oh, and just so you know, peering does not all take place on GBLX. GBLX is just another network. If Comcast were to peer with HE, you would bypass GBLX entirely.