Cisco Systems uBR7200 manual Verifying Spectrum Group Characteristics, MC-573, Threshold percent

Configuring Headend Broadband Access Router Features

Configuring and Activating Frequency Agility

To adjust the frequency hop threshold percentage or the minimum period between frequency hops, use the following commands in global configuration mode:

	Command	Purpose
Step 1
	CMTS01(config)# cable spectrum-group groupnum hop	Sets the percentage of all cable modems losing
	threshold percent	keepalive messages (going offline) that will cause a
		frequency hop.
Step 2
	CMTS01(config)# cable spectrum-group groupnum hop	Sets the minimum time between frequency hops in
	period seconds	seconds. Valid values are from 1 to 3600 seconds.

The current implementation is known as blind frequency hop because there is no “look-ahead” mechanism. In this case, the search time is 0 seconds and the switching time is 20 ms.

To specify that a particular spectrum group is a shared RF spectrum group, use the following command in global configuration mode:

Command	Purpose
CMTS01(config)# cable spectrum-group groupnum shared	Specifies a given spectrum group as “shared” and tells the
	Cisco uBR7200 series that you want to be sure that upstream
	frequencies assigned to upstream interfaces are not assigned
	to additional upstream interfaces.

Verifying Spectrum Group Characteristics

To verify spectrum group characteristics and whether or not a spectrum group is shared, enter the show cable spectrum-groupcommand:

CMTS01# show cable spectrum-group
22:07:46: %SYS-5-CONFIG_I: Configured from console by console
Group	Frequency	Upstream	Weekly Scheduled		Power	Shared
No.	Band	Port	Availability		Level	Spectrum
	(Mhz)		From Time:	To Time:	(dBmV)
1	5.000-15.000				0	Yes
1	12.000				0	Yes
1	22.000				7	Yes
2	29.000				6	No
2	26.000				0	No
3	35.000-41.000				0	No
3	16.000-19.000				5	No
5*	5.000-10.000		Thu 21:50:00	Thu 21:45:00	0	Yes

Troubleshooting Tips

To troubleshoot the configuration, perform the following tasks:

•Make sure you entered a valid spectrum group number and type.

•Make sure you are in global cable configuration mode.

Cisco IOS Multiservice Applications Configuration Guide

MC-573