Multilink Point-to-Point Protocol (MLPPP) is a protocol for aggregating multiple constituent links into one larger PPP bundle. Multilink Frame Relay (MLFR) allows you to aggregate multiple Frame Relay links by inverse multiplexing. MLPPP and MLFR provide service options between low-speed T1 and E1 services. In addition to providing additional bandwidth, bundling multiple links can add a level of fault tolerance to your dedicated access service. Because you can implement bundling across multiple interfaces, you can protect users against loss of access when a single interface fails.