BY Megan McRainey
Honeybees somehow manage to efficiently collect a lot of nectar with limited resources and no central command. Research at Georgia Tech shows the swarm intelligence also can be used to improve the efficiency of Internet servers.
A bee dance-inspired communications system developed by Georgia Tech helps Internet servers that would normally be devoted solely to one task move between tasks as needed, reducing the chances that a Web site could be overwhelmed with requests and lock out potential users and customers. Compared with the way server banks are commonly run, the honeybee method typically improves service by 4 percent to 25 percent in tests based on real Internet traffic. The research was published in the journal Bioinspiration and Biomimetics.
After studying the efficiency of honeybees, Craig Tovey, a professor in the H. Milton Stewart School of Industrial and Systems Engineering, realized through conversations with Sunil Nakrani, a computer science colleague visiting from the University of Oxford, that bees and servers had strikingly similar barriers to efficiency.
"I studied bees for years, waiting for the right application," Tovey said. "When you work with biomimetics (the study of how biological principles can be applied to design and engineering), you have to look for a close analogy between two systems — never a superficial one. And this definitely fit the bill."
The more Tovey and Nakrani discussed bees and servers, the surer they became that somehow the bees' strategies for allocating limited resources in an unpredictable and constantly changing environment could be applied to Internet servers.
Bees tackle their resource allocation problem with a seamless system driven by "dances." Here's how it works: The scout bees leave the hive in search of nectar. Once they've found a promising spot, they return to the hive and perform a dance that 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.
Tovey said the system allows the bees to seamlessly 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 said.
Internet servers, on the other hand, are theoretically optimized for "normal" conditions. 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.
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 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.
|
