Deciding the best type of WAN connections needs the knowledge of properties of these connections. Initially the main purpose of WAN networks is to move data between companys LAN Networks securely. Advantages Of Wan Disadvantages Of Wan A router is a networking device typically used to interconnect LANs to form a wide area network WAN and as such is referred to as a WAN device. . The type of device used depends on the WAN technology implemented. An organization can change the type of WAN connections being used as. A WAN is composed of three. According to Alison Adams product manager for data services at Telewest Business the ultimate disadvantage of serial leased lines is cost and relatively rigid bandwidths together with costly upgrade paths for example from an E1 to E3 or DS-3. How Wide Area Networks Function. The virtualized server and storage structure of the modern data center is an example of software-defined networki...