Cisco Catalyst 2950 User Manual

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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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Chapter 12 Configuring LRE
Configuring LRE Ports
• When the link between the LRE switch and the CPE device must co-exist in the same cable bundle
as an asymmetric digital subscriber line (ADSL), we recommend that you use either the ANSI
profile (LRE-998-15-4) or the ETSI profile (LRE-997-10-4). For details on which profile to use
elsewhere, consult the regulations for connecting to the PSTN in your area.
• LRE signaling can co-exist with ADSL signaling in one cable bundle. However, LRE signaling is
not compatible with T1 signals in the same cable bundle.
Use the show controllers lre status link privileged EXEC command to display the LRE link statistics
and profile information on the LRE ports. For information about this command, see the switch command
reference.
CPE Ethernet Link Guidelines
Follow these guidelines when configuring CPE Ethernet links:
• Guidelines for Configuring Cisco 575 LRE CPEs and 576 LRE 997 CPEs, page 12-11
• Guidelines for Configuring Cisco 585 LRE CPEs, page 12-12
Guidelines for Configuring Cisco 575 LRE CPEs and 576 LRE 997 CPEs
You can configure the CPE Ethernet port to operate at 10 or 100 Mbps and at half- or full-duplex mode,
depending on the capability of the remote Ethernet device. Autonegotiation for port speed and duplex
mode is supported.
The default speed for the CPE Ethernet port is auto. The default duplex mode is half duplex with back
pressure.
When the default speed is set to 10 or 100 Mbps with half duplex, the values set are the same. Table 12-5
shows the speed and duplex settings on the CPE Ethernet port and the switch Ethernet port.
Note The LRE link speed and duplex values are profile independent. All LRE links have a default speed of
100 Mbps with half duplex except for the profile LRE-10 (on the Catalyst 2950ST-8 LRE and 2950ST-24
LRE switches), which is set to 10 Mbps with full duplex.
The speeds on the LRE links and CPE Ethernet links do not need to match. However, to prevent the
possible loss of data when the LRE link is slower than the CPE Ethernet link, make sure that the CPE
Ethernet port is set to half-duplex mode. Use duplex autonegotiation only if the remote device supports
802.3x full-duplex flow control. The PC user should notice no significant difference in performance
Table 12-5 Speed and Duplex Settings
CPE LRE Switch
Speed Duplex Speed Duplex
10 Full 10 Half
10 Half 10 Half
100 Full 100 Half
100 Half 100 Half

Cisco Catalyst 2950 Specifications

General

Forwarding Bandwidth	8.8 Gbps
Switching Capacity	13.6 Gbps
Forwarding Rate	6.6 Mpps
Weight	3.6 kg
RAM	16 MB
Flash Memory	8 MB
Operating Humidity	10% to 85% non-condensing
Uplink Ports	2 x 10/100/1000Base-T
Dimensions	4.4 cm x 44.5 cm x 24.2 cm
Remote Management Protocol	SNMP, Telnet, HTTP
Features	Quality of Service (QoS), VLAN support
Compliant Standards	IEEE 802.3, IEEE 802.3u, IEEE 802.1D, IEEE 802.1Q, IEEE 802.1p
Status Indicators	system
Operating Temperature	0 to 45°C
Ports	24 x 10/100 Ethernet ports
MAC Address Table Size	8, 192 entries
Power Supply	Internal 100-240V AC, 50-60Hz