Configuring Maximum Hosts Attached To A Cm; Configuring Per-Modem Filters - Cisco uBR10012 Software Configuration Manual

Chapter 4 Managing Cable Modems on the Hybrid Fiber-Coaxial Network
To configure the dynamic map advance algorithm, use the following command in cable interface
configuration mode.
Command
cable map-advance
dynamic [n]|static
If you are adjusting the dynamic map-advance algorithm, do not reduce the safety factor below the
Caution
default value of 1000 usecs in a production network, until you are confident that the reduced safety factor
suffices for your deployment. The default value is chosen to be a safe operating point for the algorithm.

Configuring Maximum Hosts Attached to a CM

To specify the maximum number of hosts that can be attached to a subscriber's CM, use the following
command in cable interface configuration mode.
Command
cable max-hosts n
no cable max-hosts

Configuring Per-Modem Filters

You can configure the Cisco uBR10012 router to filter incoming packets from individual hosts or
cable interfaces based on the source Media Access Controller (MAC) or Internet Protocol (IP) address.
Definition of filters follows standard Cisco IOS configuration practices for access lists and groups.
Configuring per modem or host filters is supported in Cisco IOS Release 12.0(5)T1 or higher, as well as
Note
in Cisco IOS Release 12.0(6)SC or higher.
To configure per modem filters, use the following commands in cable interface configuration mode.
OL-1520-05
Purpose
Specifies a value to enhance the upstream throughput from a CM connected to
the Cisco uBR10012 router. The n argument provides the safety factor for the
dynamic map advance algorithm. This argument is specified in usecs and
controls the amount of extra lookahead time in MAPs to account for
inaccuracies of the measurement system and software latencies. The default
value is 1000 usecs.
You can vary this value from 500 to 1500 usecs. This argument is a delta value
added to the dynamic map-advance setting that the algorithm computes.
Using larger safety factors increases the run-time lookahead in MAPs, but
reduces the upstream performance.
Use the static keyword for the cable map-advance command. The
Cisco uBR10012 router uses a fixed lookahead time in MAPs, regardless of the
real propagation delay of the farthest CM on the network. This fixed lookahead
time is computed based on the worst-case parameters, such as farthest DOCSIS
propagation delay for the CMs.
Purpose
Specifies the maximum number of hosts that can be attached to a CM on
this interface. Valid range is from 0 to 255 hosts. Default = 0.
Resets the allowable number of hosts attached to a CM to the default value
of 0 hosts.
Cisco uBR10012 Universal Broadband Router Software Configuration Guide
Configuring Maximum Hosts Attached to a CM
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