Multilink PPP is a communications protocol that enables a personal computer (PC) to use two PPP (Point-to-Point Protocol) communications ports as if they were a single port of greater bandwidth. For example, a subscriber can use two modems to connect to the Internet, thereby obtaining a connection that works at approximately twice the data transfer rate of a single modem used alone. Multilink PPP is also known as multiPPP, MLPPP or simply MP.
The concept of MLPPP is not new. Originally, MLPPP was known as RFC 1717, published by the Internet Engineering Task Force (IETF) Network Working Group in 1994 and intended for systems using the Integrated Services Digital Network (ISDN) set of communications standards. Today, MLPPP can be used with other communications media such as telephone dial-up modems, cable modems, fiber optic systems or satellite Internet connections.
Theoretically, MLPPP makes it possible to combine connections across different media, although such implementation can be complicated in practice. The data transfer rates of the two links must be similar. Otherwise, the throughput will be dragged down by the slower link. In order to take advantage of MLPPP, two working communications links must be in place, the computer must have an operating system (OS) that supports MLPPP, and the Internet service provider (ISP) must also support MLPPP.