Multilink PPP
Multilink PPP is a non-proprietary specification that enables the bandwidth aggregation of multiple B channels into one logical pipe, providing load-balancing functionality over multiple wide area network (WAN) links, while providing packet fragmentation and proper sequencing, and load calculation on both inbound and outbound traffic. Multilink PPP enables packets to be fragmented and the fragments to be sent (at the same time) over multiple point-to-point links to the same remote address. As with BOD, the multiple links come up in response to a dialer load-threshold command. The load can be calculated on inbound traffic or outbound traffic as needed for the traffic between the specific sites. Multilink PPP provides bandwidth on demand and reduces transmission latency across WAN links. Also, as in BOD, a router running Multilink PPP recalculates the load every five minutes. You can use a show interface command to see the current load of the interface.
There are some troubleshooting commands available to resolve any issues with PPP and Multilink PPP connections. These commands include:
• show ppp multilink, which displays the current status of Multilink PPP sessions.
• show dialer, which displays active calls and status information.
• debug ppp multilink, which monitors the PPP connect phase.
• debug dialer, which is one of the best tools to use in figuring out what traffic is attempting to traverse
the ISDN link.