Testing VoIP infrastructure at scale is far from straightforward. These systems route calls and enrich the caller experience, with features such as playing prompts, interactive menus, and caller queues. With so many features and interactions, manually testing every scenario is impossible, so test automation is essential.

As a software tester for a real-world VoIP infrastructure, I built an automated framework using the open-source SIPSorcery library (https://github.com/sipsorcery-org/sipsorcery) to create programmable softphones that simulate complex call interactions. The talk covers the most interesting challenges faced, such as verifying who can be heard and seen in audio and video calls, mimicking specific physical phones, and making timing-sensitive tests run reliably.

Attendees will take away insights into the challenges of large-scale VoIP testing and practical strategies for designing automated tests that are reliable, repeatable, and maintainable.