U A| B| C| D| E| F| G| H| I| J| K| L| M| N| O| P| Q| R| S| T| U| V| W| X| Y| Z| Numerical Listing| UDP (User Datagram Protocol) A Transmission Control Protocol/Internet Protocol (TCP/IP) technology that enables an application to send a message to one of several applications running in a destination machine. Some problems arise because Internet applications are not exclusively TCP-based. UDP is stateless — it differentiates sources and destinations within hosts and provides no other services. Often services do not use predefined port numbers, so filtering on the basis of "well known ports" will not work. UI (Unix International Inc.) A Unix development company formed principally by AT&T and Sun Microsystems as a counter to the initiatives of the Open Software Foundation. Now part of Novell. Ultrix Digital Equipment Corp.’s (DEC) version of Unix, built on a University of California at Berkeley 4.2 bsd base. Unix A family of operating systems known for its relative hardware independence and portable applications interface, originating at AT&T in 1968. This time-sharing operating system is widely used in technical and scientific computing applications. It has made great strides in entering mainstream commercial computing. UNMA (Unified Network Management Architecture) AT&T’s scheme for integrated network management. TOP OF PAGE Upper-CASE Tool A tool for modeling applications requirements, systems analysis and data structure. Examples are Index Technologies’ Excelerator and KnowledgeWare’s Information Engineering Workbench. User Workbench A vision to guide the implementation of end-user computing, providing a multimedia integrated work environment, an omnipotent tool for gaining, using and communicating information, and a high level of job support to the office worker. UTP (Unshielded Twisted Pair) Two insulated wires twisted together. That is, wiring with one or more pairs of twisted insulated conductors housed in a single plastic sheath. The wires are twisted around each other to minimize interference from other twisted pairs in a cable bundle. UTP has no coaxial shielding. TOP OF PAGE UTS (Universal Time-Sharing System) In January 1986, Amdahl Corp. introduced a version of its UTS that can run stand-alone (not just as a guest under VM) on Amdahl 580 Series processors. UTS has been verified by AT&T as a Unix System V implementation. It initially ran in three modes: 1) as an operating system on an Amdahl 580 Series processor; 2) in a domain under Amdahl’s 580/Multiple Domain Feature; and 3) as a guest under VM/SP or VM/SP HPO. Amdahl has now restricted UTS to its own machines. UTS’s principal advantages over IBM’s AIX/370 product are: efficiency, support for 327X terminals and ability to run as an operating system (i.e., without a hypervisor such as VM). UTS 2.1 is the first and only Unix offering to run native on large-scale S/370-type processors. Comments? Questions? Entire contents Copyright © 1997, 1998 by Gartner Group, Inc. All rights reserved. Reproduction of this publication in any form without prior written permission is forbidden. Please read the guidelines for customer use of GartnerGroup intellecual property.