Some multiple WAN methods are defined below:
It start in 1960's. It was operated by Advanced Research Project Agency, which is a company of US defense department. It was incubator for many of current facts, algorithms and Internet methods.
It was old standard for connection-oriented networking. It start from IFU, which was started CCITT. It predates device connections, which are need for time sharing connection.
It is used for Telco service application for delivering blocks of data packets. It is connection based application and must attached with Telco for circuit between two endpoints. It is typically 1.5Mbps or 56kbps and can execute to 100Mbps.
Switched Multi megabit Data Service (SMDS) is also known as Telco service. It is a connection less application. Any SMDS station can transmit information to any station on the similar SMDS cloud. It is typically ranges from 1000Mbps to 1.5Mbps.