Secure Video Streaming in Heterogeneous Small Cell Networks With Untrusted Cache Helpers

Abstract

Abstract-This paper studies secure video streaming in cacheenabled small cell networks, where some of the cache-enabled small cell base stations (BSs) helping in video delivery are untrusted. Unfavorably, caching improves the eavesdropping capability of these untrusted helpers as they may intercept both the cached and the delivered video files. To address this issue, we propose joint caching and scalable video coding (SVC) of video files to enable secure cooperative multiple-input multipleoutput (MIMO) transmission and, at the same time, exploit the cache memory of both the trusted and untrusted BSs for improving the system performance. Considering imperfect channel state information (CSI) at the transmitters, we formulate a two-timescale non-convex mixed-integer robust optimization problem to minimize the total transmit power required for guaranteeing the quality of service (QoS) and secrecy during video streaming. We develop an iterative algorithm based on a modified generalized Benders decomposition (GBD) to solve the problem optimally, where the caching and the cooperative transmission policies are determined via offline (long-timescale) and online (short-timescale) optimization, respectively. Furthermore, inspired by the optimal algorithm, a low-complexity suboptimal algorithm based on a greedy heuristic is proposed. Simulation results show that the proposed schemes achieve significant gains in power efficiency and secrecy performance compared to several baseline schemes.

Physical Layer Security for 5G Wireless Networks: A Comprehensive Survey

“…Then, we review the most current works that address the aforementioned challenges in HetNet in the field of PLS. In two novel approaches [78], [79], PLS in a multi-cell wireless caching network has been studied. The researchers have taken advantage of cooperative multi-antenna transmissions to improve the secrecy capacity against a single eavesdropper in [78] and multiple non-reliable cache helpers in [79].…”

“…In two novel approaches [78], [79], PLS in a multi-cell wireless caching network has been studied. The researchers have taken advantage of cooperative multi-antenna transmissions to improve the secrecy capacity against a single eavesdropper in [78] and multiple non-reliable cache helpers in [79]. In [80], the authors proposed an interference-canceled opportunistic antenna selection (IC-OAS) scheme to enhance PLS for the HetNet, where a passive eavesdropper is assumed to tap the transmissions of both the macro cell and small cell.…”