A team of University of Maryland Institute for Advanced Computer Studies (UMIACS) researchers developed “provable avoidance routing” that they call Alibi Routing; it’s an overlay routing protocol that provides Internet users with a method to avoid sending their data through countries known for their censorship. Users specify where they want their packets NOT to go and Alibi Routing can provide “concrete proof” that users’ data did not pass through “undesired geographic regions.”
The researchers unveiled Alibi Routing at the 2015 Association for Computing Machinery Special Interest Group on Data Communication (ACM SIGCOMM) conference. The research paper (pdf) “introduces a primitive, provable avoidance routing that, when given a destination and region to avoid, provides ‘proof’ after the fact that a packet and its response did not traverse the forbidden region. We rely on the insight that a packet could provide an ‘alibi’—a place and time where it was—to prove that it must have avoided the forbidden region in transit from source to destination.”
“With recent events, such as censorship of Internet traffic, suspicious ‘boomerang routing’ where data leaves a region only to come back again, and monitoring of users’ data, we became increasingly interested in this notion of empowering users to have more control over what happens with their data,” said UMIACS Assistant Research Scientist Dave Levin.
If you are not concerned with censorship, then it might do you well to recall that the US government exploits loopholes in Executive Order 12333, deliberately manipulating Americans’ network traffic so that it is routed through a device located abroad, which allows the NSA to “unconstitutionally” collect and store Americans' communications.
Peers and neighbors
“A user specifies two things: who they want to communicate with (the destination), and arbitrary ‘forbidden’ geographic regions they wish to avoid while doing so.”
According to a video of the slides, “Alibi Routing is a peer-to-peer protocol for finding potential alibis.” After users choose forbidden regions and target regions where alibis might be, then “Alibi Routing recursively searches for peers within the target regions.”
Every P2P Alibi user has a set of “neighbor” peers and “every peer in the system maintains a constant-sized set of neighbors;” the team used 32 peers with diverse latency in its implementation. In theory a person would contact a peer they know and ping her.
Sign up for CIO Asia eNewsletters.