PPNDN: Popularity-based Caching for Privacy Preserving in Named Data Networking

Due to the inefficiency of present day Internet architecture, Content-Centric Networking (CCN) has been proposed to evolve the network architecture. In the CCN, every single router has cache storage to store requested contents, and uses it as a key feature to improve overall performance. Routers store all received content, until cache replacement occurs. Therefore, an attacker can infer the activity of the user connected to the access router by using the round-trip time (RTT). In this paper, we introduce a popularity-based caching strategy, PPNDN, which has been designed to prevent cache privacy violation, without compromising network performance. The popularity was measured once by the content provider at the time of creation, and kept updated by local NDN routers based on demands by local users. Adjusting cache period based on the demand makes it immune to cache privacy violation, and at the same time sustains optimal network performance. The analysis confirmed by simulation results shows that PPNDN has the lowest cache period without degrading performance, compared to other cache policies.