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arXiv · 1401.3580

Bits Through Bufferless Queues

Mehrnaz Tavan·Roy D. Yates·Waheed U. Bajwa
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Abstract

This paper investigates the capacity of a channel in which information is conveyed by the timing of consecutive packets passing through a queue with independent and identically distributed service times. Such timing channels are commonly studied under the assumption of a work-conserving queue. In contrast, this paper studies the case of a bufferless queue that drops arriving packets while a packet is in service. Under this bufferless model, the paper provides upper bounds on the capacity of timing channels and establishes achievable rates for the case of bufferless M/M/1 and M/G/1 queues. In particular, it is shown that a bufferless M/M/1 queue at worst suffers less than 10% reduction in capacity when compared to an M/M/1 work-conserving queue.

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Mehrnaz Tavan, Roy D. Yates, Waheed U. Bajwa. 2013-12-18. Bits Through Bufferless Queues. https://doi.org/10.1109/allerton.2013.6736600

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