A Triggered Delay-based Approach against Cache Privacy Attack in NDN

Content caching is one of the most significant features of Named Data Networking (NDN) that improves the performance. However, this feature makes the cache vulnerable to attacks that determine the recent cache access pattern. In cache privacy attack, an attacker can probe request and determine if the received content is cached or not, by simply observing the time difference between the requested and the received data. Existing solutions apply delay whenever the data is accessed from the cache. These approaches mitigate attack to some extent but compromise the performance of NDN. To overcome this issue, a counter scheme has been proposed in this article that detects the attack pattern at the gateway router itself and triggers the countermeasure in case of attack. The triggered-based approach delays the data accessed from the cache, only when the attack is detected instead of each time when the data is accessed from the cache. The proposed approach has been compared with an approach that induces a random delay in case of the cache hit. The results prove that the triggered delay-based approach is better than the random delay approach in terms of average delay.