Analysis of the SCAN service polling model

  Brian D. Bunday

Abstract:

  A performance analysis is given for a polling system in which the server polls stations back and forth according to the so-called SCAN system. Messages arrive at each station in Poisson fashion at an average rate . The number of characters in a message has a geometric distribution with mean . The service time per character, , and the switchover time between adjacent stations, , are both assumed to be constant.

 An exact analysis is given but because of associated computational problems this has limited application. Thus a second approximate analysis which allows systems with a large number of stations to be treated, has been developed. In both cases it is a simple matter to calculate such performance measures as average polling cycle time and mean response time at each station.

  Keywords: Machine interference models, Markov chain, Performance evaluation, Polling models, SCAN system.

 Gyenizse Pal 1996. Szeptember 4. Szerda 14:04:08 MET DST