The Akamai Protocol: Firm Rewrites Internet Rules to Speed Up its Network
Cambridge-based networking company Akamai has placed more than 28,000 of its content distribution servers around the world, creating a kind of meta-Internet atop the real Internet. And now, to make applications work across that network faster, the company is replacing the standard communications protocols that make the Internet work—namely, the Transport Control Protocol/Internet Protocol (TCP/IP) and the Hypertext Transfer Protocol (HTTP)—with its own standard, the Akamai Protocol.
The company has been working on the Akamai Protocol behind the scenes since last February. That’s when it acquired a Mountain View, CA, company called Netli and began integrating the startup’s “application acceleration” technology into its network, which it calls the Akamai EdgePlatform. Yesterday, Akamai announced that the project was essentially complete.
“The clear strengths of the EdgePlatform are its massively distributed global footprint and our real-time understanding of Internet occurrences and how to route and distribute content intelligently,” says Neil Cohen, senior manager of product marketing for Akamai’s application performance solutions division. “We had been doing some optimization at the transport layer—some tuning of the TCP/IP and HTTP protocols. But one of the key strengths of Netli was what they called the Netli Protocol, which was tuned to address transport inefficiencies in a unique way, with some enhancements above and beyond what Akamai had offered to date. So what we’re announcing is partly a repackaging of the Netli Protocol—but we get a cumulative benefit by putting that into the Akamai platform, with its routing intelligence.”
The TCP/IP protocol suite specifies how digital data should be divided into packets, labeled with address headers, passed through a network of Internet routers, and reassembled at its destination, as well as how individual Internet hosts or servers can establish temporary pipe-like connections to each other (rather than dispersing packets randomly through the network). HTTP specifies how hosts can set up connections to exchange hypertext information such as Web pages. The Internet wouldn’t work without them.
But TCP/IP was first drafted more than 30 years ago, and HTTP more than 10 years ago—long before the Internet evolved from a mere postal system for e-mail and simple Web pages into today’s global e-commerce and communications infrastructure. The protocols weren’t designed to deliver movie downloads by the gigabyte or to support the rich, interactive Flash and AJAX Web applications that now proliferate throughout the Internet. In fact, they include features that actually retard the performance of software running across the Web.
“For example, TCP has a feature built into it called ‘slow start,’ where it starts sending a little bit of information, then throttles up the rate as a function of time,” explains Cohen. “The slow start isn’t good for application performance, especially if you already have a good connection. You want to be able to immediately send more data.”
The new Akamai Protocol—which works only for communications between Akamai’s servers—does away with slow start and other procedures that gum up data transmission. It’s also more intelligent about deciding when to re-send packets that may be lost in the network.
“If you have an origin server on one side, where an application is hosted, and an end user on the other side, there are really only two variables you can improve,” says Cohen. “The first is to make sure that every time you have to send data, you do it over the most efficient route possible. That’s where the EdgePlatform’s existing ‘SureRoute’ technology comes into play. The second piece is optimizing communications, so that every time you send data over that optimal path, you do it as few times as possible. That second piece is the Akamai Protocol.”
The Akamai Protocol is already built into the existing EdgePlatform network. However, customers won’t necessarily see an immediate change in their level of service, says Cohen. “We don’t say, ‘You’re going to get an x percent increase in speed from this,” he says. “What we have are service level agreements with all our customers saying that the Akamai network is going to deliver your application x percent faster than the Internet by itself would. And SureRoute, our distributed network, and the Akamai Protocol working in concert are going to give you more predictable, more scalable performance, and more availability for your content and applications.”