Node inquiry function for strategic front-end placement

In a front-end system, mirror servers called front-ends are deployed on nodes within the Internet to enhance the quality of on-line services. An on-line service provider can control its service quality by changing the number of front-ends. In addition to the number, the placement of front-ends is also important for the provider to maximize the profitability. This paper proposes a node inquiry function (NIF) that provides on-line service providers with strategic front-end placement plans. The NIF-tailored placement plan enables a service provider to obtain the best possible front-end distribution that maximizes investment efficiency. The NIF also helps them to find those heterogeneous nodes that can run their front-ends. The placement algorithm calculates in polynomial time and an experiment shows better approximation than a greedy approach.