Abstract: A famous result of Ahlswede in the theory of Arbitrarily Varying Channels (AVCs) stated that the deterministic coding capacity of an AVC is either zero or is equal to its random coding capacity. Ericson, in 1985, gave a condition, called non-symmetrizability, and conjectured that it is necessary and sufficient for the capacity to be positive. It was established by Csiszar and Narayan in 1988. They gave an achievable scheme for the non-symmetrizable channels. This result also led to similar characterizations of other arbitrarily varying channel models.
In this talk, we will try to understand the condition of non-symmetrizability and go over the achievability scheme given by Csiszar and Narayan.
