DOCUMENT:Q151713 08-AUG-2001 [crossnet] TITLE :Description of Twisted-Pair Category Types PRODUCT :Windows for Workgroups and Windows NT Networking Issues PROD/VER:MS-DOS:3.0; WINDOWS:3.11,95; winnt:3.5,3.51; :2.2c,3.11,3.11a,3.11b OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation versions 3.5, 3.51 - Microsoft Windows NT Server versions 3.5, 3.51 - Microsoft LAN Manager, version 2.2c - Microsoft Windows for Workgroups version 3.11 - Microsoft TCP/IP-32 for Windows for Workgroups, versions 3.11, 3.11a, 3.11b - Microsoft Windows 95 - Microsoft Network Client for MS-DOS version 3.0 ------------------------------------------------------------------------------- SUMMARY ======= This article describes twisted-pair cabling and its role in the Electronic Industries Association/Telecommunications Industries Association (EIA/TIA)568 Commercial Building Wiring Standard specification. MORE INFORMATION ================ Twisted-pair consists of copper core wires surrounded by an insulator. Two wires are twisted together to form a pair, and the pair forms the circuit that can transmit data. A cable is a bundle of one or more twisted pairs surrounded by another insulator and twisted together. Unshielded twisted-pair (UTP) is common in a telephone network. Shielded twisted-pair (STP) provides protection against external crosstalk by using braided metal shielding. The twisting prevents interference problems, but must be maintained all the way to the connection points. Categories of Twisted-Pair -------------------------- The EIA/TIA 568 specification standardizes the installation of wiring. It applies to all UTP wiring schemes that work with Ethernet 10Base-T, token-ring, Private Branch Exchange (PBX), Integrated Services Digital Network (ISDN), and Twisted Pair-Physical Media Dependent (TP-PMD) networks. EIA/TIA 568 defines the following cable categories: Category 1: Unshielded twisted-pair (UTP) cable that is suited for voice but not data. Most telephone cable installed before 1983 is Category 1 cable. Not widely used anymore. Category 2: UTP cable certified for data transmissions up to 4 Mbits/second. Similar to IBM Cabling System Type 3 and is commonly installed as modern telephone cable. This cable has four twisted pairs. Category 3: UTP that supports 10-Mbits/sec transmission rates and is required for token-ring (4 Mbits/sec) and 10-Mbits/sec Ethernet 10Base-T. The cable must have four pairs and three twists per foot. Category 4: UTP certified for 16 Mbits/sec transmission rates and is the lowest grade acceptable for 16 Mbits/sec token-ring. The cable has four pairs. Category 5: Defines 100-ohm, four-wire twisted-pair UTP copper cable that can transmit data at 100 Mbits/sec to support technologies such as Fast Ethernet and Asynchronous Transfer Mode (ATM), if installed according to specifications. The cable is low-capacitance and exhibits low crosstalk. However, all components must be Category 5 compliant; therefore, older modular connectors and jacks are not suitable for Category 5 installations. REFERENCES ========== Sheldon, Tom. "LAN Times Encyclopedia of Networking." Berkeley: Osborne McGraw-Hill, 1994. Additional query words: cat1 cat2 cat3 cat4 cat5 ====================================================================== Keywords : kbnetwork Technology : kbWinNTsearch kbWinNTWsearch kbWinNT351search kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS351 kbWinNTS350 kbWinNTS351search kbWinNTS350search kbAudDeveloper kbWin95search kbZNotKeyword kbTCPIPSearch kbLanManSearch kbWFWSearch kbZNotKeyword3 kbNetworkClientSearch kbWFW311 kbLanMan220c kbNetworkClient300DOS kbTCPIP311 kbTCPIP311a kbTCPIP311b Version : MS-DOS:3.0; WINDOWS:3.11,95; winnt:3.5,3.51; :2.2c,3.11,3.11a,3.11b ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.