Rosemary Roberts

Rosemary Roberts is named as one of the two authors of the Chang and Roberts algorithm, a ring-based coordinator election algorithm for distributed computing that she published with Ernest Chang in 1979. The algorithm assumes every process has a unique identification number and that the processes are arranged in a unidirectional ring in which each sends to its clockwise neighbour. A process that notices there is no leader sends an election message carrying its own identifier around the ring, larger identifiers are forwarded, smaller ones are replaced or discarded, and the process that receives its own identifier back becomes leader and announces itself with an elected message. With a single starter the source counts at most three N minus one sequential messages in the worst case. This entry records her as co-originator of that algorithm and is not the statistics educator of the same name; no biographical page was found that would support more about her career or affiliation, so none is claimed.