Short for cable modem termination system, a system of devices located in the cable head-end that allows cable television operators to offer high-speed Internet access to home computers. The CMTS sends and receives digital cable modem signals on a cable network, receiving signals sent upstream from a user's cable modem, converting the signals into IP packets and routing the signals to an Internet Service Provide for connection to the Internet. The CMTS also can send signals downstream to the user's cable modem. Cable modems cannot communicate directly with each other; they must communicate by channeling their signals through the CMTS.
The CMTS provides many of the same functions provided by the DSLAM in a DSL system.
