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Glossary of broadband terminology: U to V
- UAWG
- Universal ADSL Working Group.
- Uniform Resource Locator
- Used with the World Wide Web as an address.
- Universal ADSL
- Also referred to as G.lite, UADSL is focused on providing a mass-market version of ADSL, which is interoperable with full rate ADSL, but with fewer complexities and less overall requirements at a tradeoff for speed. The solution is intended to reduce the need for a "splitter" box installed outside the home or new wiring in the home. UADSL enables plug-and-play and PC-integrated solutions.
- Universal ADSL Working Group
- The UAWG is composed of leading PC industry, networking, and telecommunications companies and was established to develop a set of contributions building on the T1.413 standard intended to create quick deployment and adoption of Universal ADSL (G.lite).
- Unshielded Twisted Pair
- A cable with one or more twisted copper wires bound in a plastic sheath. Preferred method to transport data and voice to business workstations and telephones. Unshielded wire is preferred for transporting high-speed data because at higher speeds radiation is created. If shielded cabling is used, the radiation is not released and creates interference.
- Unspecified Bit Rate
- Does not guarantee any throughput levels. This isused for applications, such as file transfer, that can tolerate delays.
- Upstream
- In xDSL, the communications from the customer site up into the telecommunications network.
- URL
- Uniform Resource Locator - see above
- Variable Bit Rate
- Provides a specified throughput capacity but data is not sent evenly. This is a popular choice for voice and videoconferencing data.
- VC
- see Virtual Circuit
- VDSL
- VDSL - very high rate digital subscriber line
- Very High Data Rate DSL
- Modem for twisted pair access operating at data rates from 12.9 to 52.8 Mbps with corresponding maximum reach ranging from 4,500 feet to 1,000 feet of 24-gauge twisted pair.
- Video on Demand
- The ability to activate a stored or live motion picture stream; in xDSL the application that allows subscribers to view movies or other video programming on request, similar to cable television's Pay-Per-View. See Pay-Per-View.
- Video Telephony
- The ability to view real-time video communications on a two-way or multipoint basis. Also called videoconferencing.
- Virtual Channel Identifier
- The address or label of a virtual circuit. As an ATM term, it is a unique numerical tag as defined by a 16-bit field in the ATM cell header that identifies a virtual channel, over which the cell is to travel.
- Virtual Circuit
- A logical connection or packet-switching mechanism established between two devices at the start of transmission. An interface between Access Node and network. May have multiple physical connections although may also carry all signals across a single physical connection.
- Virtual LAN
- Workstations connected to an intelligent device which provides capabilities to define LAN membership.
- Virtual Path Identifier
- As an ATM term, it is an eight-bit field in the ATM cell header which indicates the virtual path over which the cell should be routed.
- Virtual Private Network
- A network that is constructed by using public wires to connect nodes. For example, a number of systems enable creation of networks using the Internet as the medium for transporting data. These systems use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.
- Voice Frequency
- In telephony, typically the range is from zero to four KiloHertz.
