Wired.com has an interesting story about how an ISP Quarrel Partitions Internet. Cogent Communications, a US-based ISP shut down all connection with a Swedish ISP, Telia that made it impossible for Cogent customers to reach Telia customers on the Internet and vice-versa. And we thought the Internet was designed to bypass blockage! It turns out certain ISPs can arbitrarily block interconnection when in commercial disputes. They can do this by de-peering to disconnect from another ISP and then packet filtering of those packets that work their way through other channels.
This raises questions about the standard story of the Internet that presents packet-switching as a technology that makes it impossible for the Internet to be censored. As we have discovered under the general rubric of net neutrality, the ISPs now have the technology to block, slow, and filter packets (and have done so.) Thanks to Nancy for this.