Digital Workplaces increasingly consolidate collaborative tools, yet telephony often remains isolated and difficult to integrate. User needs show that a unified interface, including VoIP, simplifies the user experience while reducing vendors and costs. Once treated as a silo, telephony is now starting to become a central component of collaborative platforms.

This presentation will cover the key technical integration points for adding a a softphone application and a VoIP calling service to a Digital Workplace: embedding a web-based calling client into an existing interface, managing SSO and account provisioning, unifying call histories and presence information, ensuring interoperability between system notifications and platform notifications, and adapting the user interface.

We will illustrate these points with a concrete example using the SIP client Linphone and the SIP server Flexisip, demonstrating how an open source VoIP solution can be technically integrated into a collaborative platform: adapting WebRTC to SIP, handling push notifications for incoming calls, retrieving call logs via an API, and more.

The goal is to show how telephony can become a modular building block for collaboration rather than an isolated tool, and why this approach is essential for open source Digital Workplaces like Nextcloud, OpenDesk, or eXo Platform to offer a complete solution. It is only by combining the strengths of different specialized open-source software editors that it may be possible to compete with major players in the collaborative-software market, such as Microsoft 365.