Revisiting Zero-Rate Bounds on the Reliability Function of Discrete Memoryless Channels

We present a revised proof of Berlekamp’s zero-rate upper bound on the reliability function of discrete memoryless channels, in its extended form for list-decoding as first proved by Blinovsky. The available proofs are somehow uneasy in that they contain in one form or another some cumbersome "nonstandard" procedures or computations. Here we start from Blinovsky’s ideas and complement them with some missing steps to present a proof which is entirely in the realm of standard information theoretic tools even for general list size.