New internet routing method allows users to avoid sending data through undesired countries

August 18, 2015, University of Maryland
Credit: Wikipedia

Censorship is one of the greatest threats to open communication on the Internet. Information may be censored by a user's country of residence or the information's desired destination. But recent studies show that censorship by countries through which the data travels along its route is also a danger.

Now, computer scientists at the University of Maryland have developed a method for providing concrete proof to Internet that their information did not cross through certain geographic areas. The new system offers advantages over existing systems: it is immediately deployable and does not require knowledge of—or modifications to—the Internet's routing hardware or policies.

"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," says project lead Dave Levin, an assistant research scientist in the University of Maryland Institute for Advanced Computer Studies (UMIACS).

This new system, called Alibi Routing, will be presented on August 20, 2015, at the Association for Computing Machinery Special Interest Group on Data Communication (ACM SIGCOMM) conference in London. Levin teamed with associate professor Neil Spring and professor Bobby Bhattacharjee, who have appointments in UMD's Department of Computer Science and UMIACS, on the paper.

Information transmitted over the Internet, such as website requests or email content, is broken into packets and sent through a series of routers on the way to its destination. However, users have very little control over what parts of the world these packets traverse.

Some parts of the world have been known to modify data returned to users, thus censoring content. In 2012, researchers demonstrated that Domain Name System (DNS) queries that merely pass through China's borders are subject to the same risk as if the requests came from one of the country's own residents.

To evaluate their Alibi Routing method, the researchers simulated a network with 20,000 participants and selected forbidden regions from the 2012 "Enemies of the Internet" report published by Reporters Without Borders—China, Syria, North Korea and Saudi Arabia—as well as the three other countries with the highest number of Internet users at the time of the study—the United States, China and Japan.

Alibi Routing works by searching a peer-to-peer network to locate "peers"—other users running the alibi routing software—that can relay a user's packets to its ultimate destination while avoiding specified forbidden regions. The peer is called an "alibi." The alibi provides proof—calculations that exploit the fact that information cannot travel faster than the speed of light—that at a particular time, a packet was at a specific geographic location sufficiently far enough away from the forbidden areas that the data could not have entered them.

If successful, users receive proof that their information reached its desired destination and that it did not traverse the forbidden regions. Alternatively, the response could indicate that the packets may have traversed forbidden areas.

Levin says the success rate for Alibi Routing depends on a few things, including how close the source and destination are to the forbidden region and how central the forbidden region is to Internet routing.

"There's also a safety parameter that we use. Basically, it's a way for users to select a desired level of confidence that the packet absolutely does not traverse the forbidden region," Levin says. "The larger the safety parameter, the harder it is to find an alibi. The smaller the safety parameter, the easier it is to find an alibi."

Based on simulated deployments, the system successfully found an alibi more than 85 percent of the time. With a small safety parameter, the success rate rose to 95 percent. The results suggest that users can typically avoid the part of the world they wish to route around, according to Levin.

Users do not always need an alibi, though. If two users are in the same room in Maryland and they want their information to avoid China, they don't need an alibi to help them; they can just send the data directly to one another and measure the time it takes to do so.

"For some of the countries we tested, we only needed an alibi about one-third of the time" says Levin.

The team plans to release a version of Alibi Routing—likely as an Internet browser plug-in—for users to test by the end of 2015.

"The more participants this type of peer-to-peer system has in different geographical locations, the more useful it will be," says Levin.

Explore further: Researchers mount successful attacks against Tor network—and show how to prevent them

More information: The conference paper, "Alibi Routing," Dave Levin, Youndo Lee, Luke Valenta, Zhihao Li, Victoria Lai, Cristian Lumezanu, Neil Spring, Bobby Bhattacharjee, was presented August 20, 2015 at ACM SIGCOMM in London. … /pdf/papers/p611.pdf

Related Stories

Where do most of the Internet users live?

July 13, 2015

Dr Mark Graham and Dr Ralph Straumann, researchers at the Oxford Internet Institute, have created a global map showing the total number of Internet users in different countries.

Internet architecture is at odds with its use

August 23, 2012

The largest manmade structure is now used much differently than was originally intended by its designers. Of all Internet communication, only a fraction of traffic is intended to be exchanged between specific network elements ...

Nearly half of China's population now online

July 23, 2015

China has 668 million Internet users, accounting for 48.8 percent of the country's total population, as e-commerce boomed in the world's second-largest economy, authorities said.

China's online population nears 650 million

January 26, 2015

The number of Internet users in China has risen to nearly 650 million, authorities said over the weekend, as the world's largest online population continues to rise.

We the Internet: Bitcoin developers seed idea for Bitcloud

January 27, 2014

( —A developer group is seeding a project that would behave as a decentralized Internet, in a departure from the present model. Posting their intentions recently on Reddit, they said "We will have to start by decentralizing ...

Recommended for you

Technology near for real-time TV political fact checks

January 18, 2019

A Duke University team expects to have a product available for election year that will allow television networks to offer real-time fact checks onscreen when a politician makes a questionable claim during a speech or debate.

Privacy becomes a selling point at tech show

January 7, 2019

Apple is not among the exhibitors at the 2019 Consumer Electronics Show, but that didn't prevent the iPhone maker from sending a message to attendees on a large billboard.

China's Huawei unveils chip for global big data market

January 7, 2019

Huawei Technologies Ltd. showed off a new processor chip for data centers and cloud computing Monday, expanding into new and growing markets despite Western warnings the company might be a security risk.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.