Short for uninterruptible power supply, a power supply that includes a battery to maintain power in the event of a power outage. Typically, a UPS keeps a computer running for several minutes after a power outage, enabling you to save data that is in RAM and shut down the computer gracefully. Many UPSs now offer a software component that enables you to automate backup and shut down procedures in case there’s a power failure while you’re away from the computer.
There are two basic types of UPS systems: standby power systems (SPSs) and on-line UPS systems. An SPS monitors the power line and switches to battery power as soon as it detects a problem. The switch to battery, however, can require several milliseconds, during which time the computer is not receiving any power. Standby Power Systems are sometimes called Line-interactive UPSes.
An on-line UPS avoids these momentary power lapses by constantly providing power from its own inverter, even when the power line is functioning properly. In general, on-line UPSs are much more expensive than SPSs.
Short for Uniform Resource Identifier, the generic term for all types of names and addresses that refer to objects on the World Wide Web. A URLis one kind of URI.
Short for Universal Plug and Play, a networking architecture that provides compatibility among networking equipment, software and peripherals of the 400+ vendors that are part of the Universal Plug and Play Forum. UPnP works with wired or wireless networks and can be supported on any operating system. UPnP boasts device-driver independence and zero-configuration networking.
Communication that takes place over a network between a single sender and a single receiver. Compare with multicast and anycast.
Pronounced V-dot -twenty-two, V.22 is short for the CCITT V.22 communications standard. See under CCITT.
Pronounced V-dot -twenty-two-biss, V.22bis is short for the CCITT V.22bis communications standard. See under CCITT.