Communication Servers designed to support hundreds or thousands of users reached their peak capabilities just as dial-up service access began to recede in importance. In fact, many network engineers today have probably never managed a dial-up communications server, which were once used to connect everything from individual users to services like AOL and remote workers to entire sites (hence OSPF's demand circuit capability). Kevin Herbert joins us to discuss the early work on communication servers, including some of the challenges of working with early networking hardware.