Bees' swarm intelligence should be applied to Internet servers

do the bees manage to keep a steady flow of nectar coming into the hive? Internet servers, which provide the computing power necessary to run Web sites, typically have a set number of servers devoted to a certain Web site or client. When users access a Web site, the servers provide computing power until all the requests to access and use the site have been fulfilled. Sometimes there are a lot of requests to access a site (for instance, a clothing company’s retail site after a particularly effective television ad during a popular sporting event) and sometimes there are very few. Predicting demand for Web sites, including whether a user will access a video clip or initiate a purchase, is very difficult in constantly changing Internet landscape, and servers are frequently overloaded and later become completely inactive at random.

Bees tackle their resource allocation problem (that is, a limited number of bees and unpredictable demand on their time and desired location) with a seamless system driven by “dances.” It works this way: The scout bees leave the hive in search of nectar. Once they have found a promising spot, they return to the hive “dance floor” and perform a dance. The direction of the dance tells the waiting forager bees which direction to fly, the number of waggle turns conveys the distance to the flower patch, and the length conveys the sweetness of the nectar. The forager bees then dance behind the scouts until they learn the right steps (and the particulars about the nectar), forming what may well be described as a bobbing conga line. Then they fly out to collect the nectar detailed in the dance. As long as there is still nectar to be found, the bees that return continue the dance. Other forager bees continue to fly toward the source until the dancing slowly tapers off or a new bee returns with a more appealing dance routine, directing the forager bees to a different location. All that dancing may appear to be a model of efficiency, but it is actually optimal for the unpredictable nectar world the bees inhabit, Tovey said. The system allows the bees seamlessly to shift from one nectar source to a more promising nectar source based on up-to-the-minute conditions. All this without a clear leader or central command to slow the decision making process. “But the bees aren’t performing a computation or strategy, they ARE the computation,” Tovey added.

Internet servers, on the other hand, are theoretically optimized for “normal” conditions, which are frequently challenged by fickle human nature. By assigning certain servers to a certain Web site, Internet hosts are establishing a system that works well under normal conditions and poorly under conditions that strain demand. When demand for one site swells, many servers sit idly by as the assigned servers reach capacity and begin shifting potential users to a lengthening queue that tries their patience and turns away potential customers. Tovey and Nakrani set to work translating the bee strategy for these idle Internet servers. They developed a virtual “dance floor” for a network of servers. When one server receives a user request for a certain Web site, an internal advertisement (standing in a little less colorfully for the dance) is placed on the dance floor to attract any available servers. The ad’s duration depends on the demand on the site and how much revenue its users may generate. The longer an ad remains on the dance floor, the more power available servers devote to serving the Web site requests advertised.

-read more in Sunil Nakrani and Craig Tovey, “From Honeybees to Internet Servers: Biomimicry for Distributed Management of Internet Hosting Centers,” Bioinspiration & Biomimetics 2 (16 October 2007): 182