Lre Port - Cisco Catalyst 2950 Hardware Installation Manual

Chapter 2 Overview
Front-Panel Description
You can connect a 100BASE-FX or 1000BASE-SX port to an SC or ST port on a
target device by using one of the MT-RJ fiber-optic patch cables listed in
Table 3-1 on page 3-36. Use the Cisco part numbers in Table 3-1 to order the
patch cables that you need.

LRE Port

The LRE port (shown in Figure 2-8) uses one RJ-21 connector to connect up to
24 Cisco LRE CPE devices through 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) over distances of up to
4921 feet (1500 meters).
Certain Catalyst 2950 LRE switches support certain Cisco LRE CPE devices.
Table 2-1 on page 2-4 shows which LRE switches support which CPE devices.
You can connect the Cisco 575 LRE CPE and Cisco 585 LRE CPE devices to LRE
ports on the same Catalyst 2950ST-8 LRE or 2950ST-24 LRE switch. You can
connect the Cisco 576 LRE CPE 997 device only to LRE ports on a
Catalyst 2950ST-24 LRE 997 switch. 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 autosensing and half-duplex
operation. For information about configuring the LRE ports, refer to the switch
software configuration guide.
If telephone services, such as voice or an Integrated Services Digital Network
(ISDN), use the same cabling as LRE traffic, the LRE port must be connected to
the patch panel through a 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 PBX switch, a
non-homologated POTS splitter, such as the Cisco LRE 48 POTS Splitter, can be
used. The PBX routes voice traffic to private telephone networks and the PSTN.
For more information about the Cisco LRE 48 POTS Splitter (PS-1M-LRE-48),
refer to the Installation and Warranty Notes for the Cisco LRE 48 POTS Splitter.
For limitations and restrictions when you use a POTS splitter with the
Catalyst 2950 LRE switches and Cisco LRE CPE, see the "Limitations and
Restrictions with POTS Splitters" section on page 3-39.
Catalyst 2950 Desktop Switch Hardware Installation Guide
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