Michael Gastpar: Communication and Computation

Communication and Computation - Two Sides of One Tapestry

Networks have been studied in depth for several decades, but one aspect has received little attention: Interference. Most networks use clever algorithms to avoid interference, and this strategy has proved effective for traditional supply-chain or wired communication networks. However, the emergence of wireless networks revealed that simply avoiding interference leads to significant performance loss. A wealth of cooperative communication strategies have recently been developed to address this issue. Two fundamental roadblocks are emerging: First, it is ultimately unclear how to integrate cooperative techniques into the larger fabric of networks (short of case-by-case redesigns); and second, the lack of source/channel separation in networks (i.e., more bits do not imply better end-to-end signal quality) calls for ever more specialized cooperative techniques. This proposal advocates a new understanding of interference as computation: Interference garbles together inputs to produce an output. This can be thought of as a certain computation, perhaps subject to noise or other stochastic effects. The proposed work will develop strategies that permit to exploit this computational potential. Building on these 'computation codes,' an enhanced physical layer is proposed: Rather than only forwarding bits, the revised physical layer can also forward functions from several transmitting nodes to a receiver, much more efficiently than the full information. Near-seamless integration into the fabric of existing network architectures is thus possible, providing a solution for the first roadblock. In response to the second roadblock, computation codes suggest new computational primitives as fundamental currencies of information.

Max ERC funding: 1.78 million Euros
Duration: 60 months
Host institution: EPFL
Project acronym: COMCOM
Domain: Physical and Engineering Sciences