Modeling a Bulletin Board Service based on Broadcast Channels with Memory

The publication of the election data is fundamental for mak- ing electronic voting systems universally verifiable. For this, voting protocols usually rely on a secure bulletin board, which keeps track of the data produced during the protocol execution. This paper presents a general model for implementing such a bulletin board service. The design of the model is based on the concept of an ideal broadcast channel with memory, which transmits messages without loss of information to a present or future receiver. The challenge of implementing a bulletin board service is to approximate the properties of such an ideal channel to the best possible degree. Our model contributes to a better understanding of these properties and may help in designing future bulletin board implementations.