Cisco AS5350 - Universal Access Server Configuration Manual page 144

Enabling QoS Features for VoIP
Tip For more information and configuration options, see the following:
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•
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Resource Reservation
You can set things up so that your and any other similarly-set-up sending or receiving system can reserve
bandwidth, on a call-by-call basis, along a router path by enabling RSVP (Resource Reservation
Protocol) on all WAN links that transport voice traffic.
Configure RSVP when you configure dial peers. Do not enable RSVP in conjunction with Frame Relay
traffic shaping.
Tip For more information and configuration options, see Voice over IP for the Cisco AS5300, available online
at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t3/voip5300/
Call-Admission Control
You can gracefully prevent calls from entering your Cisco AS5850 from the PSTN when certain
resources—such as CPU, memory, and interfaces—are not available to process those calls. Such
intervention is called call-admission control.
If your system experiences high CPU usage, large call volumes, or occasional large numbers of
simultaneous calls, you need to control two specific aspects of call-admission control: call spikes and
call thresholds. Doing so is especially important if you handle transactions involving debit cards, which
require AAA and similar types of support.
Configure call spikes to limit the number of incoming calls over a short period of time. Configure call
thresholds to define under which circumstances system resources should be enabled.
Tips For more information and configuration options, including how to configure limits on call spikes and
call thresholds, refer to the following document:
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Cisco AS5350 and Cisco AS5400 Universal Gateway Software Configuration Guide
6-18
Voice over IP Quality of Service for Low-Speed PPP Links, available online at
http://www.cisco.com/warp/public/788/voice-qos/voip-mlppp.html
IP RTP Priority, available online at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t5/iprtp.htm
Frame Relay IP RTP Priority, available online at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t7/
friprtp.htm
Call Admission Control for H.323 VoIP Gateways, available online at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122limit/122x/122xa/
122xa_2/ft_pfavb.htm
Chapter 6 Configuring Voice over IP
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