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Authentication schemes for multimedia streams: Quantitative analysis and comparison

With the rapid increase in the demand for multimedia services, securing the delivery of multimedia content has become an important issue. Accordingly, the problem of multimedia stream authentication has received considerable attention by previous research and various solutions have been proposed. However, these solutions have not been rigorously analyzed and contrasted to each other, and thus their relative suitability for different streaming environments is not clear. This article presents comprehensive analysis and comparison among different schemes proposed in the literature to authenticate multimedia streams. Authentication schemes for nonscalable and scalable multimedia streams are analyzed. To conduct this analysis, we define five important performance metrics, which are computation cost, communication overhead, receiver buffer size, delay, and tolerance to packet losses. We derive analytic formulas for these metrics for all considered authentication schemes to numerically analyze their performance. In addition, we implement all schemes in a simulator to study and compare their performance in different environments. The parameters for the simulator are carefully chosen to mimic realistic settings. We draw several conclusions on the advantages and disadvantages of each scheme. We extend our analysis to authentication techniques for scalable streams. We pay careful attention to the flexibility of scalable streams and analyze its impacts on the authentication schemes. Our analysis and comparison reveal the merits and shortcomings of each scheme, provide guidelines on choosing the most appropriate scheme for a given multimedia streaming application, and could stimulate designing new authentication schemes or improving existing ones. For example, our detailed analysis has led us to design a new authentication scheme that combines the best features of two previous schemes.