Method and apparatus for authentication of data streams with adaptively controlled losses

Abstract

Methods, components, and systems for efficient authentication, either through a digital signature or message authentication codes, and verification of a digital stream sent from a source to a receiver via zero or more intermediaries, such that the source or intermediary (or both) can remove certain portions of the data stream without inhibiting the ability of the ultimate receiver to verify the authenticity and integrity of the data received. According to the invention, a source may sign an entire data stream once, but may permit either itself or an intermediary to efficiently remove certain portions of the stream before transmitting the stream to the ultimate recipient, without having to re-sign the entire stream. Applications may include the signing of media streams which often need to be further processed to accommodate the resource requirements of a particular environment. Another application allows an intermediary to choose an advertisement to include in a given slot.