Scoping Contact Graph-Routing Scalability: Investigating the System's Usability in Space-Vehicle Communication Networks

Delay-tolerant networking (DTN) is considered one of the most suitable technologies to handle challenging space-vehicle communications. Routing is critical in the DTN architecture. Contact graph routing (CGR) is a dynamic system that computes routes through a time-varying topology of scheduled communication contacts in the DTN architecture. There is an urgent need to study the scalability of CGR to very large networks. Following a discussion of CGR's operation, we present a performance evaluation of CGR over time-varying topologies of a range of sizes. The intent is to have an understanding of its usability in a space-vehicle communication network with a large number of nodes.