Fun with Routing

What has Star Wars got to do with how things find their way on the internet?

When information is sent over the network it is broken down into pieces that we call packets. Each packet is sent to the destination, but it doesn’t just appear at the destination in one jump, instead it gets passed from device to device along a route until it finally arrives where it is meant to be.

Normally, we don’t see that process happening. When we type http://www.facebook.com into a web browser the process of routing that request to Facebook and then routing Facebook’s response back to our device is hidden from us.

However, on many devices we can use a tool called tracert to trace the route to a remote destination. Here’s an example for facebook.com:

Tracert

For each step in the route, tracert displays either the IP Address or the hostname for the device. (You can find details of the tracert command on Microsoft’s technet site.)

If you don’t have a tool like tracert on your device (or your network administrator has restricted access) then you can try an online version like http://ping.eu/traceroute/.

Tracert is useful for showing you the logical route that packets follow. But it doesn’t tell us where those packets go in the real world. Each device that the packet is routed to is located somewhere, but where?

Here’s a map that shows the (approximate) physical locations of the devices along the route from my device to a proxyserver (a tool at you get signal that creates the map) and then on to Facebook.com. That’s about 11,000 miles (or about 17,800 km).

PhysicalTracert

You can use the same tool to explore the physical routes that data takes around the internet for sites that you’re interested in (if you don’t know the IP Address you can use http://ping.eu/ping/ to find it from a Hostname).

So what about Star Wars? It turns out you can have fun when you combine the names of devices on a network and the route that packets take between them.

Don’t believe me? Then before you read on try your own tracert to 216.81.59.173 (use tracert or http://ping.eu/traceroute).

Did you spot anything interesting in the output…

1 static.185.212.4.46.clients.your-server.de 46.4.212.185 de 2.528 ms 2.543 ms 2.592 ms 
2 hos-tr2.juniper1.rz13.hetzner.de 213.239.224.33 de 0.116 ms     
3 hos-bb2.juniper4.ffm.hetzner.de 213.239.240.150 de 5.835 ms 5.812 ms 5.811 ms 
4 30gigabitethernet4-3.core1.fra1.he.net 80.81.192.172 de 6.276 ms 6.564 ms 10.862 ms 
5 10gigabitethernet2-2.core1.par2.he.net 72.52.92.26 us 15.400 ms 15.399 ms   
6 10gigabitethernet7-1.core1.ash1.he.net 184.105.213.93 us 97.882 ms 93.381 ms 97.961 ms 
7 10gigabitethernet1-2.core1.atl1.he.net 184.105.213.110 us 113.166 ms 110.783 ms 110.190 ms 
8       * * * 
9       * * * 
10 Episode.IV 206.214.251.1 ca 146.517 ms 147.857 ms 149.604 ms 
11 A.NEW.HOPE 206.214.251.6 ca 149.879 ms 144.903 ms 146.521 ms 
12 It.is.a.period.of.civil.war 206.214.251.9 ca 145.616 ms 145.140 ms 147.057 ms 
13 Rebel.spaceships 206.214.251.14 ca 148.711 ms 148.598 ms 152.242 ms 
14 striking.from.a.hidden.base 206.214.251.17 ca 151.316 ms 156.136 ms 150.014 ms 
15 have.won.their.first.victory 206.214.251.22 ca 156.975 ms 149.081 ms 154.827 ms 
16 against.the.evil.Galactic.Empire 206.214.251.25 ca 153.602 ms 157.748 ms 151.427 ms 
17 During.the.battle 206.214.251.30 ca 148.135 ms 147.670 ms 145.417 ms 
18 Rebel.spies.managed 206.214.251.33 ca 145.463 ms 145.548 ms 148.795 ms 
19 to.steal.secret.plans 206.214.251.38 ca 148.798 ms 150.194 ms 149.907 ms 
20 to.the.Empires.ultimate.weapon 206.214.251.41 ca 150.064 ms 150.150 ms 151.529 ms 
21 the.DEATH.STAR 206.214.251.46 ca 149.156 ms 150.662 ms 150.111 ms 
22 an.armored.space.station 206.214.251.49 ca 146.652 ms 149.435 ms 147.558 ms 
23 with.enough.power.to 206.214.251.54 ca 146.323 ms 147.111 ms 147.798 ms 
24 destroy.an.entire.planet 206.214.251.57 ca 148.084 ms 147.699 ms 149.626 ms 
25 Pursued.by.the.Empires 206.214.251.62 ca 150.039 ms 149.873 ms 150.890 ms 
26 sinister.agents 206.214.251.65 ca 148.990 ms 145.939 ms 149.734 ms 
27 Princess.Leia.races.home 206.214.251.70 ca 150.523 ms 149.185 ms 148.577 ms 
28 aboard.her.starship 206.214.251.73 ca 146.527 ms 146.075 ms 148.720 ms 
29 custodian.of.the.stolen.plans 206.214.251.78 ca 147.784 ms 151.141 ms 150.891 ms 
30 that.can.save.her 206.214.251.81 ca 150.693 ms 150.550 ms 148.468 ms 

I wonder what Darth would think of all this…

More?

For more details of what’s going on underneath all this, check out this video from caida.org.

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