— Security and QoS are two main issues for a successful wide deployment of multicast services. For instance, in a multicast streaming application, a receiver would require a data origin authentication service as well as a quality adaptation technique for the received stream. Signature propagation and layered multicast are efficient solutions satisfying these two requirements. In this paper we investigate the use of signature propagation to ensure data origin authentication service. We, then, propose a set of novel data origin authentication techniques for layered media-streaming video. In addition to data origin authentication, the proposed techniques offer continuous non-repudiation of the origin and data integrity. These techniques take advantage of the preestablished layered structure of the encoded video data to reduce the overhead and improve the overall verification in lossy network environments. We evaluate the performance of the proposed techniques through extensive simulat...