An efficient hybrid multicast transport protocol for collaborative virtual environment with networked haptic

In recent years, we have witnessed a growing interest in synchronous collaboration based class of applications. Several techniques for collaborative virtual environments CVE, haptic, audio and visual environments C-HAVE were designed. However several challenging issues remain to be resolved before CVE and C-HAVE become a common place. In this paper, we focus upon applications that are based on closely coupled and highly synchronized haptic tasks that require a high- level of coordination among the participants. Four main protocols were designed to resolve the synchronization issues in such environments: the synchronous collaboration transport protocol (SCTP), the selective reliable transmission protocol (SRTP), the reliable multicast transport protocol (RMTP) and the scalable reliable multicast (SRM). While these four protocols have shown good performance for CVE and C-HAVE class of applications, none of these protocols was able to meet all the of the basic CVE requirement i.e., scalability, reliability, synchronization and minimum delays. In this paper, we present a hybrid protocol that is able to satisfy all the CVE and C-HAVE requirements and discuss its implementation