We prove that in order to communicate independent sources between various users over an  unknown medium to within various distortion levels, it is sufÞcient to consider source-channel separation  based architectures: architectures which Þrst compress the sources to within the corresponding distortion levels followed by reliable communication over the unknown medium. This reduces the universal rate-distortion communication problem of independent sources over a network to the universal reliable communication problem in networks. Note that we are not solving the reliable communication problem in networks. 

Paper at:

http://arxiv.org/abs/1002.1300