Rate adaptation in unlicensed bands under smart jamming attacks

Wireless communication protocols for unlicensed frequency bands support rate adaptation algorithms (RAAs) to cope with time-varying channel conditions. RAAs are not designed to operate against adversarial behavior, however. In this work, we analyze the vulnerabilities of two state-of-the-art RAAs, Minstrel and RARF, against a smart jamming model, whereby an adversary learns the current rate of transmission of each packet before deciding whether to jam the packet or not. Our parameterized analysis, validated by ns-3 simulations, shows that a jamming rate of only 10% is sufficient to bring the throughput of Minstrel below the base rate of 1 Mb/s, whereas RARF requires a jamming rate of 16:7%. These findings are notable since previous work showed that the randomized nature of RARF and Minstrel make them resilient to simpler jamming attacks. The paper concludes by sketching possible solutions to mitigate these sophisticated attacks.