Optimal synchronous capacity allocation for hard real-time communications with the timed token protocol
نویسندگان
چکیده
We study the problem of guaranteeing synchronous message deadlines in communication networks where the timed token medium access control protocol is employed. Synchronous capacity, deened as the maximum time for which a node can transmit its synchronous messages every time it receives the token, is a key parameter in the control of synchronous message transmission. To ensure the transmission of synchronous messages before their deadlines, synchronous capacities must be properly allocated to individual nodes. In this paper, we develop and analyze an optimal synchronous capacity allocation scheme. An optimal scheme can allocate the synchronous capacities in such a way that the synchronous message deadlines are guaranteed if there exists any allocation scheme that can do so. The optimality of the allocation scheme proposed in this paper is formally proved and the bounds for its Worst Case Achievable Utilization are derived.
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