Limit number of calls inbound from provider

[wilson_1234_2]

We have a situation where at a certain time of day, one day a week, we get overwhelmed by customers and inbound calls.

This is normal, it happens for 30 minutes on Wednesday. All other call volume is light.

On Wednesdays for thirty minutes, the volume is so high, our CUBE routers CPU reaches 100%.

All other times the system works fine with no problem. During high call volumes, the carrier gets error messages and the end result is "You have reached a non working number"

We need to limit the number of calls and send signaling to the carrier so they return a busy.

Would the best way to do this be with max-conn under the dial-peer, or using call admission control in call manager?

[James Hawkins]

From the white paper at http://www.cisco.com/en/US/prod/collateral/voicesw/ps6790/gatecont/ps5640/white_paper_c11-613550.html

Call Admission Control (CAC):

Cisco UBE supports global or interface-level CAC based on call count, CPU or memory use by using the following CLI:

call threshold global

call threshold interface

call treatment on

Cisco UBE can detect (and alter behavior) spikes in call arrival rate (useful for SIP DOS protection) by using the following CLI:

call spike

Cisco UBE supports destination-specific limits on call counts by using the following CLI:

dial-peer voice x voip

max-connection

From Command Reference

call threshold global

To enable the global resources of a gateway, use the call threshold global command in global configuration mode. To disable the global resources of the gateway, use the no form of this command.

call threshold global trigger-name low percent high percent [busyout] [treatment]

no call threshold global trigger-name

Syntax Description

trigger-name	Specifies the global resources on the gateway. The trigger-name argument can be one of the following: •cpu-5sec—CPU utilization in the last 5 seconds. •cpu-avg—Average CPU utilization. •io-mem—I/O memory utilization. •proc-mem—Processor memory utilization. •total-calls—Total number of calls. •total-mem—Total memory utilization.
low percent	Value of low threshold: Range is from 1 to 100% for the utilization triggers; 1 to 10000 calls for the total-calls.
high percent	Value of high threshold: Range is from 1 to 100% for the utilization triggers; 1 to 10000 calls for the total-calls.
busyout	(Optional) Busy out the T1/E1 channels if the resource is not available.
treatment	(Optional) Applies call treatment from the session application if the resource is not available.

Command Default

The default is busyout and treatment for global resource triggers.

Command Modes

Global configuration

Command History

Release	Modification
12.2(2)XA	This command was introduced.
12.2(4)T	The command was integrated into Cisco IOS Release 12.2(4)T. Support for the Cisco AS5300, Cisco AS5350, and Cisco AS5400 is not included in this release.
12.2(2)XB1	This command was implemented on the Cisco AS5850.
12.2(4)XM	This command was implemented on the Cisco 1750 and Cisco 1751 routers. Support for other Cisco platforms is not included in this release
12.2(8)T	This command was integrated into Cisco IOS Release 12.2(8)T and implemented on Cisco 7200 series routers. Support for the Cisco AS5300, Cisco AS5350, Cisco AS5400, and Cisco AS5850 is not included in this release.
12.2(11)T	This command was implemented on the Cisco AS5300, Cisco AS5350, Cisco AS5400, and Cisco AS5800 in this release.

Usage Guidelines

Use this command to enable a trigger and define associated parameters to allow or disallow new calls on the router. Action is enabled when the trigger value goes above the value specified by the high keyword and is disabled when the trigger drops below the value specified by the low keyword.

You can configure these triggers to calculate Resource Availability Indicator (RAI) information. An RAI is forwarded to a gatekeeper so that it can make call admission decisions. You can configure a trigger that is global to a router or is specific to an interface.

Examples

The following example shows how to busy out the total calls when a low of 5 or a high of 5000 is reached:

call threshold global total-calls low 5 high 5000 busyout

The following example shows how to busy out the average CPU utilization if a low of 5 percent or a high of 65 percent is reached:

call threshold global cpu-avg low 5 high 65 busyout

Related Commands

Command	Description
call threshold (interface)	Enables interface resources of a gateway.
call threshold poll-interval	Enables a polling interval threshold for CPU or memory.
clear call threshold	Clears enabled triggers and their associated parameters.
show call threshold	Displays enabled triggers, current values for configured triggers, and number of API calls that were made to global and interface resources.