Concepts for exchanging extra information between protocol layers transparently for the standard protocol stack

Popular applications such as conferencing or audio/video streaming over wireless networks require the transmission of data with real-time and bandwidth constraints. Due to these strong constraints, optimizing the end-to-end transmission is almost a necessity. However, applications do not deal directly with the physical level but through protocol networks, and the available transmission methods depend only on these protocols, without any respect to the considered application. In order to allow optimization of application level source coding and FEC at the network access layer in a standard protocol stack, two adaptation layers are inserted, namely source adaptation layer and channel adaptation layer, that are used to sort of bypass the Internet and transport layers.