ISDN Notes

• ALWAYS use ppp, authentication, and named dialer maps/profiles on the ISDN links.
• use shutdown ==> no shutdown to reset the BRI interfaces.

• Only interesting traffic initiates the call, all other traffic can go through.
• Only interesting traffic keeps the connection active & resets idle time.
• Interesting traffic is only locally significant.
• dialer-list/dialer-group defines the interesting traffic.

• If no dialer-group applied to interface, no call will be initated.
• When applying dial backup to legacy, the physical interface is placed in standby. When in standby, no other traffic can go through.
• When applying dial backup to dialer profiles, the dialer is placed in standby, the physical is free to be used for other services.

• "Encapsulation failed" messages means that there is no layer 3 to layer 2 mapping.