Chapter 12. Integrated Services Digital Network (ISDN)

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This chapter covers the following key topics:

• ISDN BRI and PRI

• ISDN components

• Legacy DDR concepts

• Configuring a network for ISDN

This chapter reviews Integrated Services Digital Network (ISDN) and legacy dial-on-demand routing (DDR). This chapter specifically focuses on configuring legacy DDR using an ISDN BRI on a Cisco router. This is accomplished by configuring legacy DDR between R5 and R6 in the lab. In addition, as you configure ISDN and legacy DDR, you will understand those commands useful in verifying and troubleshooting your configuration.

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