Nature Publishing Group: Nature News Feature; Networking: Four ways to reinvent the Internet
Global Environment for Network Innovations (GENI)
Center for Integrated Access Networks (CIAN)
Professor Keren Bergman's work was highlighted in the February 4, 2010 issue of Nature, in the News Feature entitled "Networking: Four ways to reinvent the Internet." The article focuses ways to fix the Internet as it struggles to keep up with the ever-increasing demands placed on it. With applications such as cloud computing, streaming audio and video, and ubiquitous mobile devices, the Internet's rapidly rising flood of information has been dealt with by updating the software and expanding the size of the data pipes. The result has been a rising sense of urgency within the networking research community - a conviction that the decades-old Internet architecture is reaching the limits of its admittedly remarkable ability to adapt and needs a fundamental overhaul. Funding initiatives such as the Global Environment for Network Innovations (GENI) have encouraged researchers to test out a plethora of ideas for reinventing the Internet.
Professor Bergman's work centers on making the pipes adaptable. The problem with the bigger-and-bigger-data-pipe approach to dealing with the Internet's growth is that it perpetuates a certain dumbness in the system, says electrical engineer Keren Bergman of Columbia University in New York. Right now, there is no way for a user to say: This ultrahigh-resolution video conference I'm in is really important, so I need to send the data with the least delay and highest bandwidth possible, or I'm just doing routine e-mail and web surfing at the moment, so feel free to prioritize other data. The network treats every bit of data the same. There is also no way for the Internet to minimize redundancy. If 1,000 people are logged into a massively multiplayer role-playing game such as World of Warcraft, the network has to provide 1,000 individual data streams, even though most are close to identical.
The result is a lot of wasted capacity, says Bergman, not to mention a lot of wasted money for users who have to pay extra for high-capacity data connections that they will need only occasionally. If the Internet could just adapt intelligently to what its users are trying to do, she says, it could run much more data though the pipes than it does now, thereby giving users much more capacity at a lower cost.
This is easier said than done, however, because the dumbness is deliberate. In an effort to simplify the engineering, Bergman explains, the architecture of the Internet is carefully segregated into 'layers' that take one another for granted. This means that application programmers, for example, don't have to worry about physical data connections when they are developing new software for streaming video or online data processing; they can just assume that the bits will flow. Likewise, engineers working on the physical connections can ignore what the applications are doing. And neither has to worry about in-between layers such as TCP/IP (Transfer Control Protocol/Internet Protocol): the fundamental Internet software that governs how digital messages are broken up into 'packets', routed to their destination, then reassembled.
But this clean separation also stops the layers from communicating with one another, says Bergman, which is exactly what they need to do if the data flow is to be managed intelligently. Working out how to create such a 'cross-layer' networking architecture is therefore one of the central goals of Bergman's Lightwave Research Laboratory at Columbia. The idea is to provide feedbacks between the physical data connection and the higher-level routing and applications layers, then to use those feedbacks to help the layers adjust to one another and optimize the network's performance.
This kind of adaptability is not new in networking, says Bergman, but it has been difficult to implement for the fibre-optic cables that are carrying more and more of the Internet's traffic. Unlike standard silicon electronics, optical data circuits are not easily programmable. As a result, many of the dozen projects now under way in her lab aim to integrate optics with programmable electronic systems.
Bergman's lab is also a key member of the NSF-funded Center for Integrated Access Networks (CIAN), a nine-university consortium headquartered at the University of Arizona in Tucson. Her group's efforts have helped to drive many of the technology development projects at the centre, which hopes to ultimately deliver data to users at rates that approach 10 gigabits a second, roughly 1,000 times faster than the average household broadband connection today. "The challenges are to deliver that information at a reasonable cost in terms of money and power," says Bergman.
This article is in reference to the optical cross-layer communications research being performed at the Lightwave Research Laboratory, within the scope of CIAN and GENI.
