This paper proposes a content-aware authentication scheme optimized to account for distortion and overhead for media streaming. When authenticated media is streamed over a lossy network, a received packet is consumed only when it is both decodable and authenticated. In most media formats, some packets are more important than others. This naturally motivates allocating more redundant authentication information for the more important packets in order to maximize their probability of authentication and thereby minimize distortion at the receiver. Toward this goal, with awareness of the media content, we formulate an optimization framework to compute an authentication graph to maximize the expected media quality at the receiver, given specific authentication overhead and knowledge of network loss rates. Experimental results with JPEG-2000 coded images demonstrate that the proposed method achieves our design goal in that the R-D curve of the authenticated image is very close to the R-D curve when no authentication is required.

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Abstract-In this paper, a new flexible layered authentication graph (FLAG)

Abstract-We define authenticated video as decoded video that results from those received packets whose authenticities have been verified. Generic data stream authentication methods usually impose overhead and dependency among packets for verification. Therefore, the conventional rate-distortion (R-D) optimized video streaming techniques produce highly sub-optimal R-D performance for authenticated video, since they do not account for the overhead and additional dependencies for authentication. In this paper, we study this practical problem and propose an Rate-Distortion-Authentication (R-D-A) optimized streaming technique for authenticated video. Based on packets' importance in terms of both video quality and authentication dependencies, the proposed technique computes a packet transmission schedule that minimizes the expected end-to-end distortion of the authenticated video at the receiver subject to a constraint on the average transmission rate. Simulation results based on H.264 JM 10.2 and NS-2 demonstrate that our proposed R-D-A optimized streaming technique substantially outperforms both prior (authentication-unaware) R-D optimized streaming techniques and data stream authentication techniques. In particular, when the channel capacity is below the source rate, the PSNR of authenticated video quickly drops to unacceptable levels using conventional R-D optimized streaming techniques, while the proposed R-D-A Optimization technique still maintains optimized video quality. Furthermore, we examine a low-complexity version of the proposed algorithm, and also an enhanced version which accounts for the multiple deadlines associated with each packet, which is introduced by stream authentication.

This paper presents a novel stream-level joint layered coding scheme for unified reliable and secure media transmission over wireless networks. The proposed scheme simultaneously protects both compressed media content and the authentication data from wireless channel impairments. Therefore, the media quality degradation incurred by both channel noise and authentication constraints can be minimized. With a prior knowledge of source coding and channel coding, the proposed joint system integrates authentication into the media error protection components to ensure 100% effective verification probability, i.e. every source decodable media unit is authenticable. In particular, by utilizing the contextual relationship, such as coding dependency and content importance between media slices for authentication hash appending, the proposed scheme generates an extremely low authentication overhead. The proposed authentication scheme is fundamentally different from many existing systems that consider the problem of authenticating media content separately from the other operations in the media transmission system. Under this joint layered coding framework, an optimal rate allocation algorithm for source coding, channel coding and media authentication is developed to guarantee the end-to-end media quality. Experiment results on JPEG 2000 images validate the proposed scheme and demonstrate that the performance of the proposed approach is approaching its upper bound, in which case no authentication is applied to the media stream.