Chapter 9. Shooting Trouble with HDLC, PPP, ISDN BRI, and Dial Backup
This chapter addresses various CCNP Support WAN topics. It includes scenarios and Trouble Tickets for High-Level Data Link Control (HDLC), Point-to-Point Protocol (PPP), Integrated Services Digital Network Basic Rate Interface (ISDN BRI), and Dial Backup. It is assumed you have internetworking experience particularly with IP and routing protocols in the WAN. You will analyze these WAN technologies individually and together for more practical application. This chapter in combination with the previous chapters prepares you for the next chapter and practical internetwork support where you must integrate various skills and predefined troubleshooting methods to solve numerous issues.
In supporting the WAN, many times the battle is deciding whether the problem is in fact yours or whether it is a service provider issue. You will analyze real-world WAN issues, identify troubleshooting targets, and document the results using ping, trace, show, clear, debug and other troubleshooting utilities. Gain practical experience by following the text, figures, and examples or use my guidelines to build the scenarios and Trouble Tickets yourself.
This chapter covers the following topics:
Scenario: Shooting Trouble on the WAN
WAN Terminology
HDLC
PPP
ISDN BRI
Dial-on-Demand Routing
Dial Backup
Trouble Tickets
Trouble Ticket Solutions
Supporting Website FilesYou can find files and links to utilities that support this book on the Cisco Press website at www.ciscopress.com/1587200570. Even if you do not have a lab, you can take advantage of the supporting configuration files including the logs to understand device input and output. The files are listed throughout the chapters in italics. In order to be able to read and work with some of the supporting files offered at www.ciscopress.com/1587200570, you may want to download some of the programs listed in Table I-1 in the Introduction. |