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Section 3.0: ISDN Configuration

3.1: Basic ISDN

  1. Configure legacy BRI on R1 and R3. Configure OSPF demand circuit for redundancy on R3.

3.2: PPP Callback

  1. Configure R1 as callback server and R3 as callback client. Do not configure dialer-map on R1, as it will retrieve the callback number from the AAA server.

  2. Configure AAA server with username "r3" and its callback attributes. Refer to Figure 1-5 for PPP callback user profile settings on ACS.

  3. As a fallback, configure PPP authentication to local and a username "r3" on R1 with callback string:

  4. aaa new-model
    aaa authentication ppp default group tacacs+ local
    aaa authorization network default group tacacs+ local 
    username r3 callback-dialstring 99281766 password 7 094F471A1A0A 

    Figure 5Figure 1-5 PPP Callback Settings on CiscoSecure ACS

    Figure 5

    Figure 5

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