WAN Troubleshooting Guide The goal of this Tutorial is to help enterprise network engineers troubleshoot typical problems that occur on Wide Area Networks (WANs) that use Cisco routers. Another goal is to help Cisco certification candidates prepare for CCNP and CCIE certifications. This Tutorial begins with a review of WAN standards and architectures. It then covers fundamental WAN troubleshooting with an emphasis on the main targets to consider when isolating a problem. These targets include cabling, CSU/DSUs, and serial interfaces on Cisco routers. The final sections cover the specifics of troubleshooting Cisco's HDLC, PPP, ISDN, and Frame Relay Become a ZONE Subscriber and gain access to all Study Guides Author: Priscilla Oppenheimer Technical Level: CCIE™ and CCNP™ CCNP-Support Date of Issue: 08-01-2023 Rating:   4 of 5    Table of Contents  Tutorial  3 Sample Study Questions  25 Study Questions  Lab abstract  Lab Scenario Return to Study Guides