© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Advanced Gateway Features Implementing SRST Gateways

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Overview of SRST Gateways SRST functionality: SRST offers basic phone functionality for remote sites to guard against outage of centralized Cisco Unified CallManager because of –WAN failure –Server breakdown Different feature sets for SCCP and SIP SRST –SRST for SCCP phones developed over years

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Overview of SRST Gateways (Cont.) SRST benefits: Business resiliency through redundant, localized call processing Intelligent and automatic failover configurationno manual IT or telecom intervention required Cost-effective operations through a converged voice and data network Centralized IP communication configuration and management Investment protection and ease of migration

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Example: SRST Functionality PSTN Phone Phone Phone Phone San Jose Chicago SRST WAN fails. Cisco Unified CallManager is not available for remote phones. 1 Phones register at SRST. 2 PSTN and internal calls can be established. 3 X IP WAN

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST Features and Capabilities Cisco Unified CallManager Cisco Unified SRST Cisco Unified SIP SRST Basic CallYes MOHYes No TranscodingYes No ConferencingYesThree-PartyNo Call CoverageAdvancedBasic Cisco Unity ExpressYes No IPMAYesNo Extension MobilityYes Active directory number No Third-Party ApplicationsYesNo

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST Features and Capabilities with MGCP Phone Phone Phone Phone San Jose Chicago SRST X WAN link fails. 3 All active ISDN calls get lost. 4 Phone2-1 initiates a call to the PSTN. 2 Works as an MGCP-controlled SRST gateway. 1 IP WAN PSTN

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST Features and Capabilities with H.323 Phone Phone Phone Phone San Jose Chicago SRST X WAN link fails. 3 All active calls stay connected until timer expiry. 4 Phone2-1 initiates a call to the PSTN. 2 Works as an H.323- based SRST gateway. 1 IP WAN PSTN

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST Operation Process Active Cisco CallManager registration. X WAN-connection fails. Phone registers with SRST gateway. SRST gateway pulls current phone config. incl. directory number and second line. Phone fully associated with SRST gateway. Cisco Unified CallManager keepalives received. Active Cisco Unified CallManager registration. Phone registers with CCM. Keepalive to Cisco CallManager every 30 seconds. Keepalive to SRST every 60 seconds.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST and Voice Mail IP WANPSTN Phone Phone Phone San Jose Chicago SRST X Phone2-2 calls Phone Gateway is in SRST mode. 1 Call is forwarded to Cisco Unity via the PRI circuit. 3 Phone

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v SRST and Voice Mail (Cont.) Integration via PRI circuits: With RDNIS, the original calling, called, and destination number are redirected. The called number is the original DN (RDNIS) and is required to route the call to the correct voic box. Integration via analog circuits: Configuration instructions (DTMF patterns) for the voic system are required so that the voic system can access the correct mailbox. FXO hairpin-forwarded calls to voic systems must have disconnect supervision from the central office. Each voic system requires its own special patterns to correctly interpret DTMF tones and route calls.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v call-manager-fallback router(config)# Enters SRST configuration mode call application alternate [application-name] router(config)# Specifies an alternate application to use if the application that is configured in the dial peer fails Basic SRST Commands Enable SRST: ccm-manager fallback-mgcp router(config)# Enables fallback for MGCP gateways

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v max-dn value [dual-line] [preference preference-order] router(config-cm-fallback)# Sets the maximum number of directory numbers or virtual voice ports that are supported by the router and activates the dual-line mode Basic SRST Commands (Cont.) Define the maximum amount of phones and lines: max-ephones value router(config-cm-fallback)# Configures the maximum number of Cisco IP phones that are allowed to connect to the router ip source-address ip-address router(config-cm-fallback)# Enables the router to receive messages from Cisco IP phones through the specified IP addresses

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v system message primary message router(config-cm-fallback)# Defines system message displayed in SRST mode on IP phones supporting static text messages (e.g., Cisco Unified IP Phone 7960G and 7940G) system message secondary message router(config-cm-fallback)# Defines system messages displayed in SRST mode on IP phones with limited display space (e.g., Cisco Unified IP Phone 7910GtSW) Optional SRST Commands Configure the SRST system message:

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v user-locale country-code router(config-cm-fallback)# Selects the display language for Cisco Unified IP Phone 7940G and Cisco Unified IP Phone 7960G time-format [12|24] router(config-cm-fallback)# Sets the time format on an IP phone display Optional SRST Commands (Cont.) Configure SRST localization: date-format format router(config-cm-fallback)# Sets the date format on an IP phone display

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v moh filename router(config-cm-fallback)# Defines the MOH file used for MOH in SRST mode max-conferences value router(config-cm-fallback)# Sets the maximum number of simultaneous three-party conferences in SRST mode Optional SRST Commands (Cont.) Configure MOH and conferencing:

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v call-forward reason number router(config-cm-fallback)# Sets the number to which calls are forwarded voic number router(config-cm-fallback)# Defines the number to access the voic system from the voic button Optional SRST Commands (Cont.) Configure call forwarding and voice mail integration:

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v vm-integration router(config)# Enables in-band DTMF integration with voic systems pattern direct pattern router(config-vm-int)# Defines the number used to access the voic system from the voic button Optional SRST Commands (Cont.) Define DTMF parameters for voic integration: pattern [ext-to-ext|trunk-to-ext] [busy|no-answer] pattern router(config-vm-int)# Defines the voic integration pattern used to forward calls to the voic system

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Configuring SRST for SCCP Support At least these steps need to be performed to enable SRST for SCCP devices within a Cisco Unified CallManager environment: 1. Configure basic SRST settings on the Cisco IOS gateway. 2. Configure the SRST reference on the Cisco Unified CallManager. 3. Assign an SRST reference to IP phones on Cisco Unified CallManager.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SRST for SCCP Support: Scenario PSTN SRST Router Configure SRST on the H.323 gateway. Define the H.323 gateway as an SRST reference for phones.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SRST for SCCP Support: Enable SRST PSTN call-manager-fallback ip source-address port 2000 max-ephones 48 max-dn 96 dual-line SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SRST for SCCP Support: Define SRST Reference PSTN SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SRST for SCCP Support: Assign an SRST Reference to Devices PSTN SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring Additional SRST Features for SCCP PSTN call-manager-fallback max-conferences 8 gain -6 user-locale US limit-dn ip source-address port 2000 max-ephones 36 max-dn 72 dual-line system message primary Survival-Service system message secondary SRST moh MOH.wav time-format 12 date-format mm-dd-yy SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v voice service voip Router(config)# Enters voice-service-VoIP configuration mode sip router(conf-voi-serv)# Enables SIP signaling for the VoIP service and enters SIP configuration mode SIP SRST Commands Enable SIP voice service for SIP SRST: allow-connections sip to sip router(conf-voi-serv)# Allows connections from SIP peers (e.g., phones) to SIP peers

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v registrar server Router(conf-serv-sip)# Enables SIP registrar functionality voice register pool tag router(config)# Enters voice register pool configuration mode for SIP phones SIP SRST Commands (Cont.) Configure SIP SRST registration: id [network|ip-address|mac-address] router(config-cm-fallback)# Allows registration of an individual or a set of SIP IP phones

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v voice register global Router(config)# Enters voice register global configuration mode for SIP SRST max-pool [value] router(config-register-global)# Sets the maximum number of SIP voice register pools that are supported in a Cisco SIP SRST environment SIP SRST Commands (Cont.) Enable SIP SRST registration:

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Configuring SIP SRST At least these steps need to be performed to enable SRST for SIP devices within a Cisco Unified CallManager environment: 1. Configure SIP VoIP service and SIP SRST registration settings on the Cisco IOS gateway. 2. Configure an SRST reference on Cisco Unified CallManager. 3. Assign an SRST reference to IP phones on Cisco Unified CallManager.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SIP SRST: Assign an SRST Reference to Devices PSTN SRST Router Configure additional settings on the SRST gateway that are necessary to support SIP SRST. Define the H.323 gateway as an SRST reference for SIP IP phones.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SIP SRST: Enable SIP SRST Registration PSTN voice service voip allow-connections sip to sip sip registrar server ! voice register global max-pool 10 ! voice register pool 1 id network mask SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SIP SRST: Define an SRST Reference PSTN SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Phone Phone Configuring SIP SRST: Assign an SRST Reference to Devices PSTN SRST Router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v show call-manager-fallback all Router# Displays the status of the Cisco SRST feature show ephone router# Displays Cisco IP phones that are registered to the Cisco SRST router Verifying SRST Operation Cisco IOS SRST verification commands: debug ephone register router# Debug registration information of Cisco IP phones registered to the Cisco SRST router

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Verifying SRST Operation (Cont.) SRST verification directly on a Cisco IP phone: Use network settings display to verify that the SRST device on the phones matches the IP address of the Cisco SRST router. Cisco IP phones display a message informing you that they are operating in Cisco Unified CallManager fallback mode.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Summary SRST enables basic call functionality for multisite networks with centralized call processing in case of network failures. In contrast to Cisco Unified CallManager, SRST features are extremely limited. Available functions depend on the protocols used. Within an SRST environment, the IP phone itself recognizes if the connection to the Cisco Unified CallManager fails and registers at the SRST router. There are several commands to configure SIP and SCCP SRST on Cisco IOS routers. To enable SRST for SCCP phones, it is necessary to configure an SRST reference on Cisco Unified CallManager and the SRST functionality on the Cisco IOS voice gateway.

© 2006 Cisco Systems, Inc. All rights reserved. GWGK v Summary (Cont.) Additional SRST Features for SCCP can be configured on Cisco IOS. To enable SRST to support SIP phones as well, it is necessary to enable the SIP service on the Cisco IOS gateway and allow registration of SIP phones. The SRST operation can be verified on Cisco IOS using show and debug commands and directly on Cisco IP phones.

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