Tech

Inter-Office Trunks

Published on:

June 21, 2013

Previous versions of the PBX allowed calls from one trunk to be routed through another for cost-effective call termination - this was commonly used by international offices. Now, the new inter-office trunk feature enhances this by assigning a dial plan directly to the trunk, offering greater flexibility in caller ID presentation. This allows businesses to optimize call routing without linking to specific extensions. While prepaid accounts aren’t supported, the feature enables broader applications, such as acting as a session border controller (SBC), handling LAN-WAN traffic, and translating calls between IPv4 and IPv6. Available from version 5.0.10i, this expands the role of the PBX in networked environments.

In previous versions of the PBX, there was already a setting, “assume the call comes from extension so-and-so”. This was a trick to make it possible for a call coming in on one trunk to end up on another trunk for outbound call termination.

The practical relevance for this was international offices could use this trick to locally terminate calls from their branch offices. For example, when a company had offices in Boston and Berlin, making a phone call in Germany from the Boston office could be done using the PBX in the Berlin office, saving international call termination fees.

We have now taken this to the next level by adding an “inter-office” trunk feature. Instead of using the dial plan of an extension, the trunk uses a dial plan directly. It also provides more flexibility in presenting the caller-ID: the presented caller-ID does not have to be linked to an extension. Of course this depends on the carrier’s ability and willingness to present caller-ID that aren't within the PBX address range.

Because extensions aren't charged any more, the interoffice trunk feature doesn't support prepaid accounts. Our feeling, however, is the practical relevance for this is relatively low anyway.

The term “office” goes beyond the example which I have made previously. Technically the PBX identified inbound traffic attached to a trunk, no matter if the call came from the same organization or from another source. This way, the PBX is able to perform general call routing functions and act as a general-purpose session border controller. Especially since the PBX is able to operate on multiple network interfaces, it can be used to translate traffic between LAN and WAN. Other scenarios, like translating calls between IPv4 and IPv6, or just transcoding codecs, are now also possible. Time will tell what customers want to see.

The inter-office trunk feature will be available from version 5.0.10i onwards.

Latest Articles

View All

Improve Customer Experience with Vodia’s Agent Activity Dashboard

Every missed call or unresolved issue can cost your business, making agent performance critical for call center success. The Vodia Agent Activity Dashboard provides real-time insights into agent availability, queue performance, and call metrics, enabling supervisors to quickly identify performance gaps, optimize productivity, and enhance customer experience. Agents receive actionable feedback and targeted training, while teams gain the visibility needed to manage workloads efficiently and maintain high service standards. With live monitoring, historical analytics, and smart queue indicators, Vodia ensures every customer interaction is handled effectively, helping businesses stay ahead of expectations and deliver exceptional support.

September 30, 2025

Vodia Brings the Future of Hospitality Communication to NoVacancy Sydney 2025

Vodia participated in NoVacancy Sydney 2025, Australia’s largest conference and exhibition for the accommodation industry, showcasing its cloud PBX solutions designed specifically for hotels, resorts, and other hospitality venues. With advanced VoIP and AI-driven features, Vodia enables properties to provide guests with seamless, personalized experiences while streamlining operations, reducing costs, and boosting staff efficiency. The company highlighted its recent integration with the Shiji Property Management System (PMS) and Microsoft Teams certification, making it a versatile communication platform for both boutique hotels and multinational chains.

September 26, 2025

The Vodia Call Recordings and Transcription Dashboard

The Vodia Call Recordings and Transcription Dashboard is a modern, powerful tool for businesses to manage and analyze call activity efficiently. Its sleek interface provides a widescreen view of key call metrics including average call length, calls per day, and ongoing calls in real time. With filtering, analytics, transcription, and export options, users can easily access, playback, and share recordings. Designed for industries requiring call recording for legal compliance such as healthcare, government, and utilities, it ensures secure storage, encrypted sharing, and more. Combining robust functionality with a user-friendly design, it helps businesses improve customer service, monitor staff performance, resolve disputes, and gain insights.

September 25, 2025