Pentagon uses 'Onion Routing' to hide says Navy Labs at Usenix Conference
During an afternoon presentation at the Usenix Security conference on Thursday, a researcher at the U.S. Naval Research Laboratory described a technology known as "Onion Routing," which preserves anonymity by wrapping the identity of users in onion-like layers.
"Public networks are vulnerable to traffic analysis. Packet headers identify recipients, and packet routes can be tracked," said Paul Syverson, who works at the NRL's Center for High Assurance Computer Systems. "Even encrypted data exposes the identity of the communicating parties."
Even if you bother to scramble the contents of your message, someone snooping your e-mail or Web-browsing habits can still see your Internet address and the address of the person or website with whom you're communicating. In other words, if you're a CIA or military intelligence agent, you don't want to visit the website of an underground group and risk revealing you're coming from a dot-mil network.....
The Onion Routing solution, which follows much the same recipe as Zero Knowledge's Freedom software and cypherpunk-developed mixmaster remailers, is to forward communications through a complicated network that bounces Internet packets around like pinballs and hides the origin and destination from all but the most determined eavesdroppers.
Syverson said that the U.S. government was awarded patent number 6,266,704 for Onion Routing on July 24.
That announcement prompted an angry reaction from Usenix attendees, many of whom are programmers, security consultants and system administrators, who aren't big fans of software patents -- especially in the area of anonymous communications, where there's been so much prior work before the Navy ever got involved.
Mathematician David Chaum, for instance, wrote an article titled "Untraceable Electronic Mail, Return Addresses and Digital Pseudonyms" for Communications of the ACM as far back as 1981. Lance Cottrell, who now runs anonymizer.com, wrote part of the mixmaster system in the early 1990s, and similar techniques were discussed on the cypherpunks mailing list even earlier.
