Delays and mixing times in random-access networks
Proceedings of the ACM SIGMETRICS/international conference on Measurement and modeling of computer systems
CSMA over time-varying channels: optimality, uniqueness and limited backoff rate
Proceedings of the fourteenth ACM international symposium on Mobile ad hoc networking and computing
Delay performance in random-access grid networks
Performance Evaluation
Throughput-optimal CSMA with imperfect carrier sensing
IEEE/ACM Transactions on Networking (TON)
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Consider a wireless network of n nodes represented by a (undirected) graph G where an edge (i,j) models the fact that transmissions of i and j interfere with each other, i.e. simultaneous transmissions of i and j become unsuccessful. Hence it is required that at each time instance a set of non-interfering nodes (corresponding to an independent set in G) access the wireless medium. To utilize wireless resources efficiently, it is required to arbitrate the access of medium among interfering nodes properly. Moreover, to be of practical use, such a mechanism is required to be totally distributed as well as simple. As the main result of this paper, we provide such a medium access algorithm. It is randomized, totally distributed and simple: each node attempts to access medium at each time with probability that is a function of its local information. We establish efficiency of the algorithm by showing that the corresponding network Markov chain is positive recurrent as long as the demand imposed on the network can be supported by the wireless network (using any algorithm). In that sense, the proposed algorithm is optimal in terms of utilizing wireless resources. The algorithm is oblivious to the network graph structure, in contrast with the so-called polynomial back-off algorithm by Hastad-Leighton-Rogoff (STOC '87, SICOMP '96) that is established to be optimal for the complete graph and bipartite graphs (by Goldberg-MacKenzie (SODA '96, JCSS '99)).