Analysis Of M-states Stop-and-Wait ARQ Protocol

Error control technique is an important ingredient in maintaining good quality data transmission. Automatic Repeat Request (ARQ) is one of the main error control procedures. There are three basic ARQ protocols: Stop-and-wait (SW), Go-back-N (GBN), and Selective-repeat (SR).In this paper, first, we study the behavior of the transmitter buffer of a system working under a Stop-and -wait ARQ protocol with an assumption that the feedback errors will not happen. The buffer at the transmitter side is modeled as discrete-time infinite-capacity queue. The numbers of information packets entering the buffer during consecutive slots are assumed to be independent and identically distributed random variables. The packets are sent over an unreliable channel and transmission errors in a correlated manner.And later, we consider the issue of errors in the feedback channel. In some applications, such as digital mobile communications, this issue can be important. According, this paper examines the effect of feedback errors of the stop-and-wait ARQ protocol for the case of a point-to-point channel under some feedback information assumptions.In the Stop-and-wait ARQ protocol, we consider the case the probability of an erroneous packet depends on what state the channel is in when the packet is transmitted. Specifically, the channel state process is modeled by an M-state Markov chain with a fixed error probability in each state.