Structured virtual synchrony: exploring the bounds of virtual synchronous group communication

Abstract

Multipoint communication protocols that offer group membership and virtually synchronous message delivery are commonly believed to be heavyweight and non-scalable. To meet the needs of large-scale computer-supported collaborative work, distributed parallel computing, and future worldwide applications, we designed the Structured Virtual Synchrony (SVS) protocol. The protocol has been implemented as part of Horus, a group communication system developed at Cornell University. It scales up to 800 members, while achieving a one-way latency of 100 milliseconds over groups of 500 members.