Cisco 2970 Hardware Installation Guide - Page 27

Chapter 1 Product Overview Front-Panel Description 100BASE-FX Ports The 100BASE-FX ports use 50/125- or 62.5/125-micron multimode fiber-optic cabling. The connection distances between the switch and the attached device can be as follows: • If the switch port and the port on the attached device are configured for half-duplex operation, the connection can be up to 1352 feet (412 meters). • If the switch port and the port on the attached device are configured for full-duplex operation, the connection can be over distances of up to 6562 feet (2 kilometers). Long-Reach Ethernet Ports The Long-Reach Ethernet (LRE) ports (Figure 1-4) use one RJ-21 connector to connect up to 24 Cisco LRE customer premises equipment (CPE) devices though structured or unstructured wiring, such as existing telephone lines. The link between the LRE switch port and each CPE device can reach speeds of up to 15 Mbps (full duplex) and distances of up to 4921 feet (1500 meters). You can connect Cisco 575 LRE CPE and Cisco 585 LRE CPE devices to LRE ports on the same Catalyst 2900 LRE XL switch, and you can hot swap the CPE devices without powering down the switch or disrupting the other switch ports. The default mode for each LRE port is speed autonegotiation and half-duplex operation. For information about configuring the LRE ports, refer to the Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide. For more information about the Cisco LRE CPE devices, refer to the Cisco LRE CPE Hardware Installation Guide. If telephone services, such as voice or integrated services digital network (ISDN), use the same cabling as LRE traffic, the LRE port must be connected to the patch panel through a basic telephone service, also known as plain old telephone service (POTS) splitter. The splitter routes LRE data (high-frequency) and voice (low-frequency) traffic from the telephone line to the switch and private branch exchange (PBX) switch or Public-Switched Telephone Network (PSTN). If the other telephone services are connected through a private branch exchange (PBX) switch, a Cisco LRE 48 POTS Splitter can be used. The PBX routes voice traffic to private telephone networks and the public system telephone network 78-6461-04 Catalyst 2900 Series XL Hardware Installation Guide 1-7