IP Paging: Using the PBX as a GatewayIP Paging: Using the PBX as a Gateway

IP solutions can be integrated with older gear such as hybrid and TDM systems.

We've discussed campus paging before, from the lens of using an IP solution or UC communications server from Panasonic. But there are still older hybrid and TDM PBXs that need good solutions for paging.

Plenty of schools hang on to aging paging gear, which not only takes up space, but can also yield high costs for maintenance and repairs. In some cases, upkeep isn't a viable option because the gear is so old that repairs remain costly even if you can get the service and/or required parts.

I've taken multiple approaches to implementing paging solutions. I briefly tested an older hybrid Panasonic system, and then went on to test and implement an IP paging solution from Algo Communications using the Panasonic NCS-1000.. The older gear (hybrid and TDM systems) often interfaces through an RCA cable or an analog trunk interface.

Integrating an IP paging solution with multiple zones with the Panasonic NCP-1000 hybrid system proved to be challenging. The support folks at Jenne Distributors tech support were especially helpful leading us in the right direction. They suggested using a SIP trunk interface with the IP paging system so we could then use the onboard broadcast features for zone paging with the Algo solution.

We also worked with both Panasonic and Algo tech support on how it would integrate and operate. We made minor changes to the SIP registration and then placed the trunk in a trunk group with a dial access code (DAC). The DAC is followed with two station digits - XX (definable) and then # and X (X= 0 through 9 for zone paging). The dial string is 8XX+XX+#+X. Both the PBX and Algo alerters use RFC 2833 for passing DTMF, and this is key. (For more information, Andrew Prokop provides a good primer on DTMF and RFC2833 in his SIP Adventures blog.)

The dial strings are easily preprogrammed in both the UC client soft keys and desk telephones so users can just press a button or soft key (ALL PAGE or Page Zone 1, Page Zone 2, etc.). With one master controller/speaker, all other paging speakers (alerters) are configured as members of page zones and/or ALL PAGE.

As with any integration effort, there were some specific programming requirements and customization. In this case they were minor; just time consuming in testing and retesting to understand the behaviors.

The Algo solution effectively eliminates a paging zone controller by using a master speaker as the controller with DTMF to direct the pages. One alternative would be to use individual master speakers as controllers for each zone, but this means adding more hardware (higher costs) to the solution.

IP solutions can be integrated with older gear such as hybrid and TDM systems. This is important because the newer IP solution should be able to integrate with newer premises or hosted solutions, offering customers investment protection and at least a migration path.

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