An information-centric version of the Internet would include several fundamental changes: For starters, data packets would be labeled according to the information they contain rather than an IP address. Ideally, this change would give Internet users more direct control over their personal information, allowing them to restrict access to their data and monitor how and when it is accessed. "Such control is achieved by tying the security of the content to the identification of it," says Dirk Trossen, a senior researcher at the University of Cambridge Computer Laboratory's Networks and Operating Systems group.
The ICN model also proposes that users retrieve information from locations closest to them, a process much more efficient than the current approach of routing information requests throughout the Internet. If an Internet user in the U.S. is looking for the latest BBC news, for example, this information is likely to exist in cache memory in computers within the U.S., Trossen explains. The ability to access this data domestically, rather than routing the same content from computers in the U.K., reduces traffic over a larger expanse of network.
Trossen is the lead researcher on an ICN project called Publish Subscribe Internet Technology (PURSUIT), which espouses a variation on the "publish-and-subscribe" model already popular with Internet users who sign up for RSS feeds and e-mail distribution lists, to name a few. In principle, a network built using the PURSUIT model would ensure that users receive only content in which they have explicitly expressed an interest. This specificity would go far toward cutting down on spam and computer viruses as well as speeding up network traffic.
The three-year, $6.7-million PURSUIT Internet improvement project—essentially a continuation of the work begun in the Publish–Subscribe Internet Routing Paradigm (PSIRP) Project from January 2008 to June 2010—wraps up in February. Based in Europe, it includes eight research organizations across Finland, Germany, Greece and the U.K. (pdf). After February Trossen and his colleagues plan to demonstrate a prototype PURSUIT network known as Blackadder to technology companies and other researchers who might be interested in continuing and/or funding this work.
One of these demos is designed to show the PURSUIT network's resilience in delivering data to subscribers even if part of the network becomes disconnected. A second demo illustrates PURSUIT's ability to adjust the delivery of streaming video based on a particular country's constraints on what it considers objectionable content. "Since the various pieces of data are individually identified, they are automatically retrieved from the nearest cache storage where they are available," Trossen says. "You can then replace any offending content piece with an alternative clip while leaving the rest of the content intact."
Trossen and his team want to expand their Blackadder PURSUIT-based network beyond its current 40 nodes so that it includes hundreds of devices sending and receiving data. Only at this scale and beyond can the researchers determine how well their publish-and-subscribe model will hold up and whether the idea merits further investment.
Whether PURSUIT, PARC's CCNx or one of the various other ICN projects under development operate in conjunction with each other or independently remains to be seen. It is likely, however, that one or more of them is necessary to ensure the Internet can evolve to meet the ever-increasing demands placed on it.