Tech

Multicast Paging for the Hosted PBX

Published on:

March 26, 2014

Hosted PBX offers many advantages over local systems, but when it comes to paging phones in a LAN, multicast remains the most efficient solution. Unfortunately, multicast often doesn't work in hosted PBX environments or large corporate networks. One workaround is using a unicast stream that is then converted into multicast through a device in the LAN, often using iptables. Another option is to use snom phones or the PA1, which can convert the audio stream into multicast. Alternatively, a local Vodia mini PBX can be set up to register with the hosted PBX, sending calls to a multicast paging group. This method offers more flexibility and useful features like call recording, making it an ideal solution for handling large volumes of paging.

Hosted PBX has a lot of advantages compared to the PBX running locally. However when it comes to paging phones in the LAN, multicast is still the best way to achieve that: Instead of sending an audio stream to each and every phone, the PBX just sends out a single multicast stream that addresses all phones that should be playing back the audio stream. This works well in the LAN; but it almost never works in the hosted PBX. Also, in large corporate networks multicast packets usually also don’t make it from the PBX to the phones.

There are several ways to address the problem. The first one is to have the PBX send out a unicast stream to a device in the LAN that translates the stream into a multicast stream. This is a kind of routing functionality. This could be achieved by tweaking iptables, so that every incoming UDP packet on port so-and-so gets send out to a multicast IP address. For those who are familiar with iptables and have a Linux host in the LAN anyway, this might be a viable solution.

For the rest of us, there are two more possible solutions. First, the snom phones and foremost the PA1 have a remarkable feature that instead of sending out the audio data on a speaker, the device may send the data out on a multicast stream. If you run the PA1 on premises and register it to the hosted PBX, you can send the paging call to one of the registered account. The device will then take care about the local multicast.

The other solution is to run a Vodia mini PBX locally. All you need to do is set up a trunk that registers with the PBX and sends all calls to a paging group. That groups needs to operate in multicast mode. This solution has a few benefits compared to the solution with the PA1. First, the number of groups that can be set up this way, is not limited. Secondly, the features to announce the paging can be used locally. You can even have the PBX record the call first and play back the recording after the call was recorded. This is very useful for situations where echo problems make paging difficult or where there are so many pages going on that they need to be lined up.

This actually works not only for Vodia hosted PBX. This works for practically all hosted PBX that support SIP registrations. Because paging uses only the basic SIP features, the interoperability is simple.

Derniers articles

Voir tous

The Vodia PBX On-Premise Whisper AI Deployment​

Whisper, OpenAI’s Automatic Speech Recognition system, delivers multilingual, noise-tolerant, and technical-language-ready transcription through a streamlined encoder-decoder architecture. With Vodia PBX’s integration, organizations can choose between using OpenAI’s service or hosting Whisper AI locally for complete data sovereignty and control. This on-premise option ensures that sensitive call data stays within your infrastructure while still benefiting from powerful transcription capabilities. To explore deployment options, see our Whisper AI on-premise setup documentation, review a self-hosted integration example, or follow our cloud-based call transcription guide.

March 27, 2025

Vodia Will Attend Seatrade Cruise Global 2025

Vodia is excited to attend Seatrade Cruise Global 2025, marking the event’s 40th anniversary, taking place in Miami from April 7-10. In partnership with Lufthansa Industry Solutions, Vodia will showcase the Vodia Maritime Communication Server (Vodia MCS)—a next-generation solution designed to seamlessly integrate voice, video, and messaging within cruise ship communications. Engineered for both new vessels and retrofits, the Vodia MCS enhances onboard connectivity, passenger experience, and operational efficiency, while supporting essential maritime safety and security systems. Join us at booth #3608 to discover how Vodia MCS is reshaping onboard communication in the cruise industry.

March 24, 2025

The Vodia PBX Gives Hotels a Peerless Suite of Hospitality Features

Vodia PBX delivers a comprehensive hospitality communication system that enhances guest experience and streamlines hotel operations. With support for multiple device types, seamless PMS integration, in-house call center functionality, and Microsoft Teams connectivity, hotels can optimize efficiency while maintaining high-quality service. Guests can easily access hotel services, communicate with staff, and integrate their personal devices for a seamless and convenient stay. Advanced automation, multilingual support, AI-driven call management, and building automation features further enhance functionality, making Vodia PBX a powerful, scalable solution for modern hospitality environments.

March 20, 2025