Internet routing over large public data networks using shortcuts

Abstract

With the emergence of large switched public data networks that are well-suited to connectionless internets, for instance SMDS, it is possible that larger and larger numbers of internet users will get their connectivity from large public data networks whose native protocols are not the same as the user's internet protocol. This results in a routing problem that has not yet been addressed. That is, large numbers of routers (potentially tens of thousands) must be able to find direct routes to each other in a robust and efficient way. This paper describes a solution to the problem, called shortcut routing, that incorporates 1) a sparse graph of logical connectivity between routers, 2) hierarchical addressing among the public data network subscribers, and 3) the use of “entry router” information in packets to allow routers to find one hop “shortcuts” across the multi-hop logical graph.