SOFA: Strategyproof Online Frequency Allocation for Multihop Wireless Networks

A number of approaches, including cognitive radios, dynamic spectrum allocation, and spectrum auction, have been proposed and used to improve the spectrum usage. A natural characteristic of spectrum usage is that requests for spectrums often come in an online fashion. Thus, it is imperative to design efficient and effective online dynamic spectrum allocation methods. Another challenge is that the secondary users are often selfish and prefer to maximize their own benefits. In this paper, we address these two challenges by proposing SOFA, strategyproof online frequency allocation method. In our protocol, a frequency will be shared among a number of users, and secondary users are required to submit the spectrum bid α time slots before its usage. Upon receiving an online spectrum request, our protocol will decide whether to grant its exclusive usage, within γ time slots. Assume that existing spectrum usage can be preempted with some penalty. For various possible known information, we analytically prove that the competitive ratios of our methods are within small constant factors of the optimum online method. Furthermore, in our mechanisms, no selfish users will gain benefits by bidding lower than its willing payment.