Limitations And Restrictions With Pots Splitters - Cisco WS-C2950T-48-SI Hardware Installation Manual

Chapter 2 Installation

Limitations and Restrictions with POTS Splitters

These limitations and restrictions apply when you use a POTS splitter with Catalyst 2950 LRE switches
and Cisco LRE CPE devices:
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•
•
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Figure 2-37 Limitations Using a Cisco LRE 48 POTS Splitter with a Catalyst 2950ST-24 LRE 997 Switch
POTS Telephone
OL-6156-01
The Catalyst 2950ST-8 LRE switch, Catalyst 2950ST-24 LRE switch, Cisco 575 LRE CPE, and
Cisco 585 LRE CPE are designed to share lines with analog, ISDN, and digital PBX switch
telephones that use the 0 to 700 kHz frequency range.
Digital telephones connected to digital PBX switches that use frequencies above 700 kHz do not
work when sharing a line with LRE signals. Due to the proprietary nature of digital PBX switches,
some digital PBX switch services use frequencies above 700 kHz.
You can use a Cisco LRE 48 POTS Splitter with a Catalyst 2950ST-8 LRE switch, Catalyst
2950ST-24 LRE switch, Cisco 575 LRE CPE, and Cisco 585 LRE CPE. For installation instructions,
see the Installation and Warranty Notes for the Cisco LRE 48 POTS Splitter.
The Catalyst 2950ST-24 LRE 997 switch and Cisco 576 LRE 997 CPE are designed to share lines
with analog and ISDN telephones that use the 0
to 120 kHz frequency range.
We recommend that you do not use a Cisco LRE 48 POTS Splitter with a Catalyst 2950ST-24
LRE 997 switch and a Cisco 576 LRE 997 CPE as shown in
frequency range can be sent to and from the devices attached to the CPE.
In Figure 2-37, only traffic from 0 to 120 kHz can pass from a device attached to the CPE, such as
a computer or telephone, to the CPE, a splitter, and a switch. In the reverse direction, traffic from 0
to 700 kHz can pass through the switch and splitter to the CPE, but only traffic from 0 to 120 kHz
can pass through the CPE to a computer or a telephone.
For more information, see the Installation and Warranty Notes for the Cisco LRE 48 POTS Splitter.
and a Cisco 576 LRE 997 CPE
PC
Cisco 576 LRE
997 CPE
Traffic from
0 to 120 kHz
Cisco LRE 48 Catalyst 2950ST-24
POTS splitter LRE 997 switch
Traffic from 0 to 700 kHz
Catalyst 2950 Switch Hardware Installation Guide
Connecting to an LRE Port
Figure 2-37. Only traffic in a specific
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