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Cisco Broadband Cable Command Reference Guide
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Chapter 2 Cisco CMTS Configuration Commands
cable upstream admission-control
cable upstream admission-control
To specify the percentage overbooking rate that is allowed on an upstream channel, use the
cable upstream admission-control
command in cable interface configuration mode. To set
overbooking rate to its default of 100 percent, use the
no
form of this command.
cable upstream
n
admission-control
percentage
no cable upstream
n
admission-control
Syntax Description
Defaults
100 percent
Command Modes
Interface configuration (cable interface only)
Command History
Usage Guidelines
This command limits the maximum number of CMs for a given upstream port by looking at the minimum
guaranteed upstream bandwidth allocated to each CM. Cable modems providing residential services and
commercial services can be given different weights according to their traffic needs. This command
affects only whether CMs can register with the CMTS—it does not affect CMs that have already come
online.
The CMTS uses the minimum guaranteed upstream bandwidth field from the CM’s DOCSIS
configuration file to calculate whether the CM can come online or not. If the CM’s minimum guaranteed
upstream bandwidth would exceed the total upstream bandwidth multiplied by the overbooking
percentage specified by this command, the CM cannot come online on that upstream. The CM will
attempt to find another upstream, and if it cannot register on any upstreams, it will attempt to lock on to
a new downstream.
Note
A CM with a guaranteed upstream bandwidth does not consume that bandwidth unless it has active
traffic. By guaranteeing a CM a minimum upstream bandwidth, individual customers are assured of
never being totally shut out from network access in a very high-traffic situation.
Table 2-9
shows the approximate bandwidth for each upstream channel, depending on channel width,
symbol rate, and modulation type, when admission control is used at 100 percent. When setting
admission control to other values, scale the bandwidth values in
Table 2-9
accordingly, so as to plan for
the maximum number of CMs effectively allowed per upstream port.
n
Specifies the upstream port. Valid values start with 0 for the first
upstream port on the cable interface line card.
percentage
Specifies the percentage overbooking rate to limit overbooking. Valid
values are from 10 to 1000 percent, with a default of 100 percent.
Release
Modification
11.3(6) NA
This command was introduced.