Monday, June 27, 2011

The Internet route from Cuba to Google

The Internet is, as its name implies, a network of networks. A data packet is sent from a particular computer on one network across the Internet to the receiving computer on another network. As the packet moves from network to network, it goes through special purpose computers called routers.

Traceroute is a simple utility program that comes with every Mac or Windows computer. It shows the path a packet takes -- the list of routers that handle it -- as it hops from network to network.

A colleague in Cuba recently ran Traceroute to see the path between his computer, which was on a dial-up link, to Google in California. He saw that the packet hopped through 20 routers:
  1. 192.168.254.69
  2. 192.168.254.65
  3. 192.168.254.77
  4. 192.168.254.229
  5. 200.0.16.130
  6. 200.0.16.114
  7. 200.0.16.101
  8. 204.14.41.33
  9. 204.14.40.9
  10. 207.45.197.197
  11. 64.86.83.190
  12. 64.86.138.114
  13. 66.198.111.65
  14. 216.6.87.9
  15. 74.125.50.230
  16. 216.239.46.248
  17. 209.85.248.73
  18. 209.85.254.235
  19. 216.239.46.78
  20. 74.125.93.99
These four-number addresses, called Internet Protocol (IP) addresses, identify each router on the path between Cuba and Google, and they reveal something of the network structure.

The prefix of the first four hops (192.168) indicates that they are within the ISP's local area network. The next three are on the network of ETECSA, the Cuban telecommunication monopoly. I saw that by querying the "whois" database that shows that the IP addresses that begin "200.0" have been allocated to:

owner: CUBADATA
responsible: Rafael López Guerra
address: Ave. Independencia y 19 Mayo, s/n,
address: 10600 - La Habana - CH
country: CU
phone: +53 7 574242
e-mail: nap@ETECSA.CU
The eighth hop is over a satellite link from the router at the edge of the Cuban network to the network of Newcome International in Miami. I know it is a satellite link because Traceroute reported that the time to reach from Cuba to the 8th router was much longer than from Cuba to the 7th router. Newcome routes packets across their network from Miami to Newark New Jersey and eventually to Google.

No secrets are revealed here -- this sort of information is widely available -- but it would be interesting to see how routes and timing (which we looked at in a previous post) change when the undersea cable is operational. If you are in Cuba and would like to share this sort of route and timing data, let me know.