he M5000 series asynchronous data transmission with automatic rate adaptation makes it much simpler to use many features available on the DMS and handshaking protocols, freeing the user from the need to Centrex, thus allowing normal users to realise the benefits these get transmission parameters for each call. Datapath will also features have to offer. work into analogue data transmission systems through a DMS- based modem pool 35.2.2 Automatic call distribution 2. DataSpan, an integrated Frame Relay, based on standards rec- ommended by the CCITT. Frame Relay is a wide area 'fast' Automatic Call Distribution (ACD) is a powerful business feature packet switching technology that offers an intelligent alterna- which can be readily implemented in Centrex. It distributes large tive to private lines for data interconnection. It uses less error numbers of incoming calls equally among a designated group of checking than packet switching, optimising on the high quality answering positions, presenting the first incoming call to the posi- of transmission on digital networks. This makes it more effi- tion which has been idle longest. If all 'agents' i.e. answering cient for applications such as LAN interconnection. Existing positions, are busy, later calls are queued and answered in order of solutions for connecting several data sites require leased or arrival. Comprehensive information on the incoming calls, such as dedicated lines of fixed bandwidth in a complicated mesh. With time to answer, number of callers who abandoned while in the queue DataSpan the public network becomes a viable alternative, are all available from a management information system. eliminating the need for multiple connections; each location Current DMS systems will deliver a full ACD feature set regard- now links to the other through a single access line to the Frame less of line size, whether to a 2000-line sales or reservation system Relay network. or a 10-line group medical practice. This extends the benefits of ISDN services which realise the fu