notes: PPP Reliable Link (RFC 1663)

- Defines a method of negotiating and using Numbered Mode LAPB to provide a reliable serial link.
- Numbered Mode LAPB provides retransmission of errored packets across the serial link.
- PPP reliable link can be used with PPP compression over the link, but it does not require PPP compression.
- PPP reliable link does not work with multilink PPP.

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COMMANDS
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show int - Will show whether LAPB has been established on the link.
debug lapb - Displays all traffic for interfaces using LAPB encapsulation.

interface s0
ppp reliable-link - Enables PPP reliable-link