Cisco 2950 Hardware Installation Guide - Page 101

Appendix B Connectors and Cables Connector Specifications Connecting to 1000BASE-T Devices When connecting the ports to 1000BASE-T devices, such as servers, workstations, and routers, you must use a four twisted-pair, Category 5, straight-through cable wired for 10BASE-T, 100BASE-TX, and 1000BASE-T. Figure B-14 shows the straight-through cable schematics. When connecting the ports to other devices, such as switches or repeaters, you must use a four twisted-pair, Category 5, crossover cable. Figure B-15 shows the crossover cable schematics. Note Be sure to use a four twisted-pair, Category 5 cable when connecting to a 1000BASE-T device. Note Use a straight-through cable to connect two ports only when one port is designated with an X. Use a crossover cable to connect two ports when both ports are designated with an X or when both ports do not have an X. Figure B-2 RJ-45 Pinouts for 10/100/1000 and 1000BASE-T GBIC Module Ports Pin Label 1 TP0+ 2 TP0- 3 TP1+ 4 TP2+ 5 TP2- 6 TP1- 7 TP3+ 8 TP3- 1234567 8 34751 LRE Port The LRE port uses a single 50-pin RJ-21 connector, as shown in Figure B-3. Each LRE port uses two pins. Because the Catalyst 2950ST-24 LRE and Catalyst 2950ST-24 LRE 997 switches use 48 pins, pin 25 on the top row and pin 50 on the bottom row are not used The Catalyst 2950ST-8 LRE switch uses 16 pins. Pins 9 through 25 on the top row and pins 34 through 50 on the bottom row are not used. Figure B-3 RJ-21 Connector 25 9 1 97734 OL-6156-01 50 34 26 Catalyst 2950 Switch Hardware Installation Guide B-3