Why it mattered
A voice service that works for one call can still fail at a hundred. To test it under load you need hundreds of real calls at the same time, and something has to answer them too.
How it works
- Written from scratch in C, with both sides of the call: the caller and the answering end.
- Hundreds of parallel SIP calls from one system.
- Distributed master-worker design: a master coordinates workers on several hosts, so capacity grows by adding hosts.