If you can think of the problem, Internetworking Troubleshooting Handbook probably has the solution - at least when it comes to network problems. Although you may not find that profound scientific discussions about networking woes, you will find pragmatic tips that can help you through the immediate crisis. Divided into six sections, the first describes the general problem solving techniques and troubleshooting tools available from Cisco and third party vendors. Furthermore, the authors compete with hardware, boot, and the media (which is basically an answer to what could prevent a network router or switch from automatic to shoot up). As for WAN connectivity, more than 100 pages dedicated to serial line, dial-in, ISDN, frame relay, and X.25 connections.