Where does your email go before it gets to its destination?
I live about 7 miles from UConn, in Willimantic CT. so, what happens if i want to get some data from a website at UConn?

Here is the output of a trace-route program running against a host in a residence hall at UConn from my house in Willimantic. A description of what it means is below.
Tracing route to d153h11.resnet.uconn.edu []
over a maximum of 30 hops:

  1    11 ms    11 ms    10 ms
  2   169 ms   227 ms   192 ms
  3   235 ms   227 ms   246 ms  gbr1-a80s21.n54ny.ip.att.net []
  4   241 ms   258 ms   295 ms  gbr3-p70.n54ny.ip.att.net []
  5   294 ms   248 ms   319 ms  gbr3-p30.wswdc.ip.att.net []
  6   257 ms   286 ms   277 ms  gbr4-p60.wswdc.ip.att.net []
  7   293 ms   266 ms   253 ms  gbr4-p90.attga.ip.att.net []
  8   324 ms     *      183 ms  ggr1-p370.attga.ip.att.net []
  9   212 ms   257 ms   321 ms  atl-brdr-03.inet.qwest.net []
 10   374 ms   395 ms   344 ms  atl-core-03.inet.qwest.net []
 11   314 ms   346 ms   228 ms  atl-core-01.inet.qwest.net []
 12   332 ms   394 ms   375 ms  wdc-core-03.inet.qwest.net []
 13   341 ms   322 ms   308 ms  wdc-core-02.inet.qwest.net []
 14   372 ms   365 ms   283 ms  jfk-core-01.inet.qwest.net []
 15     *      165 ms   261 ms  jfk-edge-11.inet.qwest.net []
 16   222 ms   254 ms   342 ms
 17   230 ms   254 ms   205 ms
 18     *      378 ms   352 ms  d153h11.resnet.uconn.edu []

Trace complete.


What it means: What this program says is that first, my data leaves the charter cable modem router in willimantic and goes onto the Earthlink network. The number is the router here in Willimantic and is the point where it leaves the Earthlink network and enters the AT&T network at gbr1-a80s21.n54ny.ip.att.net as indicated by the ny in the hostname.

Since UConn is on a different network than the charter pipeline service, I would expect that any data sent between me and UConn would need to switch networks to arrive at its destination. So my data then goes to New York City on the AT&T network and is transferred from NYC to a router in Washington DC gbr3-p30.wswdc.ip.att.net (the wdc in the hostname indicates Washington DC). Washington DC appears to be a hub for most networks including Qwest, which i'll describe later.

So then inside the AT&T network, my data is sent to Atlanta gbr4-p90.attga.ip.att.net. In Atlanta, my data enters the Qwest network atl-brdr-03.inet.qwest.net. I'm not sure what the border, core, and edge labels on the Qwest hostnames indicate, however they seem to show which part of the Qwest network the router is part of. The core seems to mean that the router is connected only to other routers that are part of the Qwest network. The border seems to indicate where data enters the network and the edge seems to indicate where it leaves the network to enter another network.

My data is now in Atlanta inside the Qwest network. It then goes back to Washington DC wdc-core-03.inet.qwest.net. And from Washington, it then goes to JFK airport in New York City jfk-core-01.inet.qwest.net. From JFK it leaves the Qwest network and enters a nameless router, which appears to link UConn to the Qwest network. Then it reaches a router at UConn And from this router is goes directly a residential hall d153h11.resnet.uconn.edu.

To sum up the trip my data took from Willimantic to Storrs, which is a distance of only 8 miles, it left Willimantic and went to New York City (142 miles). Then to Washington DC (232 miles) and on to Atlanta (637 miles) where it switched networks and came back to Washington DC (637 miles). Then it went to JFK airport (234 miles) and finally to a residence hall in Storrs (141 miles). A trip of 2023 miles or 3,255,702 meters. Traveling at the speed of light, it takes 10ms round trip... with the exception of stops. each stop at a router adds time.

Here are some references:

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