Low-layer quasi-agreed order broadcast over local bus

Abstract

Agreed order broadcast protocols are supposed to deliver messages in a group wide agreed total order. With large group sizes and a faulty communication environment (e.g., prone to reception misses), existing protocols can collapse due to imperfect synchronisation mechanisms. We propose and evaluate a MAC layer Jamming Protocol (JP), applicable in Ethernet type media, whereby a site jams an out of sequence message thus preventing all other sites from delivering it. The low layer approach yields higher group throughput at the price of introducing a practically negligible possibility of violating agreed order.