Monitoring Ethernet Connectivity

Although the Ethernet promises high probability packet delivery between all pairs of hosts, defects in the installation can sometimes prevent some pairs of hosts from communicating very well. This paper describes a method that was developed and used at Carnegie Mellon University during 1984–1985 to monitor the connectivity between all pairs of hosts on the Ethernet. The method is based on sending test packets from a central station through various cyclic routes and relating the results to the likelihood of various defects via a system probability model. The method proved to be quite effective in practice and greatly assisted our support staff in maintaining our Ethernet.