Network control by bayesian broadcast

  • Authors:
  • Ronald L. Rivest

  • Affiliations:
  • MIT Laboratory for Computer Science, Cambridge, MA

  • Venue:
  • IEEE Transactions on Information Theory
  • Year:
  • 1987

Quantified Score

Hi-index 754.84

Visualization

Abstract

A transmission control strategy is described for slotted-ALOHA-type broadcast channels with ternary feedback. At each time slot, each station estimates the probability that n stations are ready to transmit a packet for eachn, using Bayes' rule and the observed history of collisions, successful transmissions, and holes (empty slots). A station transmits a packet in a probabilistic manner based on these estimates. This strategy is called Bayesian broadcast. An elegant and very practical strategy--pseudo-Bayesian broadcast--is then derived by approximating the probability estimates with a Poisson distribution with meannuand further simplifying. Each station keeps a copy ofnu, transmits a packet with probability1/nu, and then updatesnuin two steps: For collisions, incrementnuby(e-2)^{-l}=1.39221 cdots. For successes and holes, decrementnuby1. Setnutomax (nu + hat{lambda}, 1), wherehat{lambda}is an estimate of the arrival ratelambdaof new packets into the system. Simulation results are presented showing that pseudo-Bayesian broadcast performs well in practice, and methods that can be used to prove that certain versions of pseudo-Bayesian broadcast are stable forlambda < e^{-1}are discussed.