The TeleLink® DataLink system is a digital communication link for airborne networks. The TeleLink® system provides the capability to exchange messages and graphics between the aircraft and a ground-based DataLink Service Provider or host computer. At minimum, a TeleLink® network consists of a TeleLink® Router Management Unit (RMU), a Control Display Unit (CDU), and a VHF radio. Depending on the requirement for a specific installation, a TeleLink® system may also include additional CDUs, Flight Management Computers (FMCs), Satellite Data Units (SDUs), air-to ground telephone systems or cockpit printers.