I tried to traceroute someone who is a Comcast customer in TN to see what kind of route it would take. This gets really interesting.
2 134 ms 185 ms 169 ms c-3-0-ubr05.boston.ma.boston.comcast.net [73.168.144.1]
3 * 102 ms 192 ms ge-2-39-ur01.boston.ma.boston.comcast.net [68.87.158.33]
4 152 ms 142 ms 162 ms te-8-1-ur01.brookline.ma.boston.comcast.net [68.87.144.57]
5 187 ms 200 ms 183 ms te-8-3-ar01.needham.ma.boston.comcast.net [68.87.144.53]
6 25 ms 15 ms 15 ms 12.116.130.173
7 185 ms * 245 ms br2.cb1ma.ip.att.net [12.127.5.26]
8 227 ms 181 ms 226 ms tbr2.n54ny.ip.att.net [12.122.10.22]
9 * 40 ms 117 ms tbr2.wswdc.ip.att.net [12.122.10.54]
10 209 ms 216 ms 275 ms 12.122.16.77
11 202 ms 166 ms 165 ms cr1.attga.ip.att.net [12.122.1.173]
12 224 ms 179 ms 245 ms tbr1.attga.ip.att.net [12.122.12.30]
13 235 ms 251 ms 206 ms ar5.attga.ip.att.net [12.123.20.233]
14 230 ms 149 ms 185 ms 12.116.236.50
15 56 ms 69 ms 279 ms te-9-1-ur01.goodslettvll.tn.nash.comcast.net [68.86.148.22]
16 215 ms 201 ms 259 ms te-9-3-ur01.gallatin.tn.nash.comcast.net [68.86.148.62]
17 256 ms 137 ms 183 ms te-9-2-ur01.tulipgrove.tn.nash.comcast.net [68.86.148.78]
18 212 ms 223 ms 181 ms te-9-2-ur01.blebanonrd.tn.nash.comcast.net [68.86.148.86]
19 122 ms 191 ms 231 ms te-9-2-ur02.ashgroverd.tn.nash.comcast.net [68.86.148.58]
20 215 ms 165 ms 249 ms te-9-2-ur01.ashgroverd.tn.nash.comcast.net [68.86.148.53]
21 112 ms 217 ms 194 ms te-9-2-ur01.ruralhillrd.tn.nash.comcast.net [68.86.148.50]
It looks like my traffic bounced off the Comcast network in Needham and bounced onto the AT&T network from New York to Georgia and then back onto the Comcast network in Nashville.
Look at what happens when I tried to traceroute a Comcast customer in CA.
2 200 ms 116 ms 194 ms c-3-0-ubr05.boston.ma.boston.comcast.net [73.168.144.1]
3 66 ms 157 ms 196 ms ge-2-39-ur01.boston.ma.boston.comcast.net [68.87.158.33]
4 7 ms 7 ms 11 ms te-8-1-ur01.brookline.ma.boston.comcast.net [68.87.144.57]
5 91 ms 247 ms 156 ms te-8-3-ar01.needham.ma.boston.comcast.net [68.87.144.53]
6 193 ms 139 ms 168 ms po-11-ar02.needham.ma.boston.comcast.net [68.87.146.38]
7 11 ms 11 ms 8 ms po-12-ar02.woburn.ma.boston.comcast.net [68.87.146.46]
8 196 ms 205 ms 153 ms po-10-ar01.woburn.ma.boston.comcast.net [68.87.146.41]
9 169 ms 11 ms 10 ms te-4-1-cr01.boston.ma.cbone.comcast.net [68.86.72.25]
10 143 ms 219 ms 212 ms te-9-1-cr01.cleveland.oh.cbone.comcast.net [68.86.68.14]
11 86 ms 146 ms 260 ms te-9-1-cr01.chicago.il.cbone.comcast.net [68.86.68.22]
12 204 ms 137 ms 143 ms te-9-1-cr01.omaha.ne.cbone.comcast.net [68.86.68.30]
13 241 ms 174 ms * te-9-1-cr01.denver.co.cbone.comcast.net [68.86.68.42]
14 66 ms 70 ms 118 ms te-9-1-cr01.denverqwest.co.cbone.comcast.net [68.86.68.146]
15 247 ms 257 ms 141 ms te-9-1-cr01.alburquerque.nm.cbone.comcast.net [68.86.68.150]
16 280 ms 295 ms 247 ms te-8-1-cr01.losangeles.ca.cbone.comcast.net [68.86.68.81]
17 242 ms 165 ms 259 ms te-1-1-cr01.sanjose.ca.cbone.comcast.net [68.86.68.73]
18 153 ms 286 ms 282 ms 68.86.143.2
19 257 ms 283 ms 266 ms te-9-1-ur01.sfsutro.ca.sfba.comcast.net [68.87.192.198]
20 207 ms 265 ms 275 ms te-8-1-ur02.sfsutro.ca.sfba.comcast.net [68.87.226.46]
21 301 ms 265 ms 201 ms te-9-3-ur01.sffolsom.ca.sfba.comcast.net [68.87.192.202]
This time, instead of going to Hartford via Springfield, the Comcast traffic got routed to Woburn after Needham. From there, it looks like it traveled along Comcast’s “cbone” which I would assume is one of their backbones. It went back into Boston before heading to Cleveland, Chicago, Omaha, Denver, Alburquerque, Los Angeles, and San Jose, before hitting the SFBA (San Francisco Bay Area?) network.
I’m not sure why, but I find the whole concept of data routing fascinating at the moment. Maybe it’s because I can’t sleep.