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Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide
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Chapter 7 Configuring the Switch Ports
Configuring the LRE Ports
Bandwidth within the LRE link is controlled by the switch by using
configurations called profiles. An LRE profile configures the upstream and
downstream rates on the LRE link. Depending on the profile, the upstream and
downstream bands on an LRE link can be approximately 5, 10, or 15 Mbps.
You can assign profiles on a per-port or switch-wide basis. When the LRE port
establishes a link with the CPE, the switch downloads its profile settings to the
CPE port so that both ports on both devices operate with the same configuration.
The Catalyst 2900 LRE XL switches are shipped with predefined profiles
(
Table 7-1
) categorized as public (global) mode and private (per-port) mode
profiles. By default, all LRE ports on the switch are enabled with the LRE-10
private profile in effect.
•
Public—We strongly recommend using a public profile if the switch is used
with equipment connected to a Public Switched Telephone Network (PSTN).
When the switch is configured with a public profile, all LRE ports use the
same configuration to prevent the switch from causing interference with the
other lines on the PSTN.
The standards for spectral profiles have not yet been ratified. The
PUBLIC-ANSI profile corresponds to ANSI Plan 998. The PUBLIC-ETSI
profile corresponds to ETSI Plan 997. Both plans are draft standards. Contact
Cisco Systems for the latest information about standards ratification or for
updates to the public profiles.
•
Private—You can use a private profile if the LRE switch is not used with
equipment connected to a PSTN. Three private profiles offer different link
speeds and maximum distances. In general, the higher the link speed, the
shorter the maximum distance. Private profiles are assigned on a per-port
basis. The ports on an LRE switch can be assigned the same or different
private profiles.