Throughput of TCP over Cognitive Radio Channels

TL;DR

This paper analyzes TCP performance over cognitive radio channels with intermittent availability, modeling throughput and retransmission probabilities, and validating results through ns2 simulations.

Contribution

It introduces a comprehensive model for TCP over ON/OFF channels, extending to multiple connections and general distributions, validated by simulations.

Findings

Throughput varies with ON/OFF channel dynamics

Packet retransmission timeout probability is characterized

Model validated by ns2 simulations

Abstract

In this paper, we study the performance of a TCP connection over cognitive radio networks. In these networks, the network may not always be available for transmission. Also, the packets can be lost due to wireless channel impairments. We evaluate the throughput and packet retransmission timeout probability of a secondary TCP connection over an ON/OFF channel. We first assume that the ON and OFF time durations are exponential and later extend it to more general distributions. We then consider multiple TCP connections over the ON/OFF channel. We validate our theoretical models and the approximations made therein via ns2 simulations.