Lre Upbo - Cisco Catalyst 2950 Command Reference Manual

Chapter 2 Catalyst 2950 and 2955 Cisco IOS Commands

lre upbo

Use the lre upbo global configuration command to configure the reference TX power level on the
Long-Reach Ethernet (LRE) customer premises equipment (CPE) device. Use the no form of this
command to return t to the default setting.
This command is available only on Catalyst 2950 LRE switches.
Syntax Description
noise-model
offset value
Defaults
The default is the ETSI-E noise model.
Command Modes
Global configuration
Command History Release
12.1(11)YJ4
Usage Guidelines
The upstream power back-off mechanism allows for normalization of the upstream receive power levels
by requiring the CPE devices on shorter lines to transmit at a lower power level than the CPEs on longer
lines. You can change the upstream power back-off values by either selecting a standard noise model or
by setting an offset value for the default reference PSD.
The reference PSD number is based on an upstream carrier frequency of 4.8 MHz.
Note
Table 2-4
OL-10102-01
lre upbo {noise-model | offset value}
no lre upbo {noise-model | offset value}
Specify the noise model. See
supported values. Values are not case sensitive.
Specify the offset value. The range is 300 to 800.
The offset value is calculated with reference to –140 decibels referenced to 1
milliwatt per hertz (dBm/Hz). For example, if you require a reference power
spectral density (PSD) of –95.0 dBm/Hz, you need to enter an offset of 45.0
(–95.0 – [–140] = 45.0).
The LRE CPE PSD offset value is in 10*decibel (dB) (for example, 450
Note
means 45.0 dB)
Modification
This command was introduced.
shows the supported values for the noise models:
Table 2-4 in the "Usage Guidelines" section for the
Catalyst 2950 and Catalyst 2955 Switch Command Reference
lre upbo
2-181