BYZANTINE AGREEMENT IN THE PRESENCE OF MIXED FAULTS ON PROCESSORS ANDLINKS

In early stage, the Byzantine agreement (BA) problem was studied with single faults on processors in either a fully connected network or a n onfully connected network. Subsequently, the single fault assumption w as extended to mixed faults (also referred to as hybrid fault model) o n processors. For the case of both processor and link failures, the pr oblem has been examined in a fully connected network with a single fau lty type, namely an arbitrary fault. To release the limitations of a f ully connected network and a single faulty type, the problem is recons idered in a general network. The processors and links in such a networ k can both be subjected to different types of fault simultaneously. Th e proposed protocol uses the minimum number of message exchanges and c an tolerate the maximum number of allowable faulty components to make each fault-free processor reach an agreement.