© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Gatekeeper Deployments Implementing Gatekeeper-Based CAC

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Gatekeeper Zone Bandwidth Operation IP WANPSTN Phone Phone Phone San Jose Chicago Router1 (MGCP) Router2 (H.323) GK A WAN link can handle one IP voice call. There is no physical limitation on IP links. The second call can go through, but the voice quality of all calls degrades. CAC helps to prevent link over-subscription Phone Gatekeeper

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Gatekeeper Zone Bandwidth Operation (Cont.) The CAC function is an essential component of any Cisco IP Communications system that involves multiple sites connected through an IP WAN. The Cisco IOS gatekeeper can provide CAC between these devices: –Cisco Unified CallManager –Cisco Unified CallManager Express –H.323 gateways Gatekeeper CAC is a policy-based scheme requiring static configuration of available resources.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Gatekeeper in Cisco Unified CallManager Networks Phone Phone Phone Phone Phone Phone IP WAN Gatekeeper Router1 (MGCP) Zone_Company Phone3-1 calls Phone2-1: ARQ May I make a call? ACF Yes, there is enough bandwidth. After the ACF message, the call can be established Voice Call G.711 Voice Call G.729 Video Call H Voice G.711

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Gatekeeper in Cisco Unified CallManager Networks (Cont.) The gatekeeper tracks the used bandwidth into and out of a zone. Bandwidth calculations for the call ARQ do not include compressed Real-time Transport Protocol (cRTP) or any other transport overhead. The topology is a logical hub-and-spoke.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Zone Bandwidth Calculation Formula for zone bandwidth calculation on a gatekeeper –(Number of calls) x (Codec bandwidth) x 2 Example: 3 calls x G.711 x 2 3 x 64 x 2 = 384 kbps Bandwidth kbps values are different for gatekeeper and Cisco Unified CallManager. Codeckbps on CallManagerkbps on Gatekeeper G kbps128 kbps G kbps16 kbps

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Bandwidth Request Service Parameter H.323 trunks can update the gatekeeper with bandwidth information to indicate a change in the requested bandwidth allocated to a specific call. The feature is disabled by default.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Zone Bandwidth Configuration IP WANPSTN Phone Phone Phone Phone Zone SanJose Zone Chicago Router1 (MGCP) Router2 (H.323) Bandwidth configuration for all zones is done on the gatekeeper. Gatekeeper

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Zone Bandwidth Commands bandwidth {interzone | total | session} {default | zone zone-name} bandwidth-size router(config)# Used to specify the maximum aggregate bandwidth for H.323 traffic and verify the available bandwidth of the destination gatekeeper. Per default, the maximum aggregate bandwidth is unlimited.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Zone Bandwidth Configuration IP WANPSTN Phone Phone Phone Phone Zone SanJose Zone Chicago Router1 (MGCP) Router2 (H.323) Gatekeeper gatekeeper zone local SanJose cisco.com zone local Chicago cisco.com zone prefix SanJose 2... gw-priority 10 ICT_CM_1 zone prefix SanJose 2... gw-priority 9 ICT_CM_2 zone prefix Chicago 3... gw-priority 10 CME gw-type-prefix 1#* default-technology bandwidth interzone zone SanJose 384 bandwidth interzone zone Chicago 256 no shutdown

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Verifying Zone Bandwidth Operation Router#show gatekeeper zone status GATEKEEPER ZONES ================ GK name Domain Name RAS Address PORT FLAGS SanJose cisco.com LS BANDWIDTH INFORMATION (kbps) : Maximum total bandwidth : unlimited Current total bandwidth : 0 Maximum interzone bandwidth : 384 Current interzone bandwidth : 0 Maximum session bandwidth : unlimited SUBNET ATTRIBUTES : All Other Subnets : (Enabled) Displays output for the SanJose gatekeeper zone only. Only important information of the show command is displayed

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RAI in Gatekeeper Networks The gateway informs the gatekeeper when it is running short on resources: Occurs when resource usage exceeds a high water mark. DS-0s and DSPs are included in calculation. A gateway that was earlier overloaded sends another RAI to the gatekeeper when resources fall below a configured low water mark.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RAI in Gatekeeper Networks (Cont.) 100% high low 0% Gateway sends RAI unavailable. Gateway sends RAI available. Gateway A Gatekeeper RAIRAC Gateway B RAI RAC Thresholds configured on gateways A and B: DSP: Low threshold-60; High threshold-70 DS0: Low threshold-60; High threshold-70 RAI RAC H.323 resource thresholding is enabled and active.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v resource threshold [all] [high percentage-value] [low percentage-value] router(config-gateway)# To configure a gateway to report H.323 resource availability to its gatekeeper, use the resource threshold command in gateway configuration mode. High- and low-parameter settings are applied to all monitored H.323 resources. This is the default condition. Resource Threshold Command

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RAI Configuration Phone Phone Gatekeeper PSTN Gateway1 Gateway2 Which gateway should be used for the call? Wants to call PSTN phone. PSTN Phone GK RAI is configured on each gateway, that want to monitor. RAI is configured on each gateway, that you want to monitor.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v RAI Commands Phone Phone PSTN Gateway1 Wants to call PSTN phone. PSTN Phone Gateway2 gateway resource threshold high 70 low 50 Gatekeeper

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Verifying RAI Operation Router#show call resource voice threshold Resource Monitor - Dial-up Resource Threshold Information: DS0 Threshold: Client Type: h323 High Water Mark: 70 Low Water Mark: 50 Threshold State: low_threshold_hit DSP Threshold: Client Type: h323 High Water Mark: 70 Low Water Mark: 50 Threshold State: low_threshold_hit

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Verifying RAI Operation (Cont.) Show commands to verify an RAI operation: show call resource voice threshold show gateway show call resource voice stat

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Summary Zone bandwidth management is used in an H.323 network to control bandwidth in or between zones. Cisco Unified CallManager can use a gatekeeper for CAC. Bandwidth calculation can be done with an easy formula. Bandwidth commands are configured directly on the gatekeeper in the gatekeeper configuration mode. The bandwidth command is used to configure a specific bandwidth for interzone, total, session, or default zones. Several show and debug commands are available to verify and troubleshoot zone bandwidth configuration.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Summary (Cont.) RAI is used in gatekeeper networks to inform the gatekeeper about the actual status of an end device. RAI is configured on the endpoint, not on the gatekeeper. RAI commands can be configured with fixed values or with default values. Several show and debug commands are available to verify and troubleshoot RAI configuration.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v