(UDP) User Datagram Protocol: A host-to-host protocol, which allows an application program on one computer to send a datagram to an application on another computer via packet-switched communications network.
Unbundling: Requiring local exchange companies to separate the various components of their telephone service into independently available and separately priced features, such as the local loop, switching, operator assistance, and billing.
Underground Installation: Installing coaxial and fiber cable underground as opposed to hanging it from poles (compare with AERIAL PLANT).
(UNE) Unbundled Network Elements: Parts and components of a system that are sold separately, including local loops, OSS, local and tandem switches, as well as network interface devices.
Universal Service: A fund to which interstate carrier must contribute in order to provide access to the advanced interexchange telecommunications services to those people living in rural areas and where it world otherwise not be cost-efficient to invest.
Unserved Area: See WHITE AREA.
Upstream: Flow of information from a customer back up through a cable system to the headend.