Case Study: Metro Trains Melbourne achieves VoIP migration and ~60% cost savings with Digium

Australia's Metro Trains Melbourne Bridges Legacy PBX to VOLP

Metro Trains Melbourne (MTM), a major mass-transit operator serving 215 stations and over 3,000 employees across Melbourne, needed to replace an aging legacy PBX that was showing capacity limits and line faults. With more than 900 telephony end-points — including auto-answer public-address and on-demand service units — MTM required a staged migration to VoIP to improve communications reliability and deliver more accurate passenger information without a risky “big bang” cutover.

MTM implemented a customized Asterisk-based solution, using Digium analog cards to bridge the existing PBX while rolling out SIP-capable IP endpoints. The deployment digitizes and delivers audio to stations and control centers, removes line-capacity constraints, simplifies integrations (including emergency and PA systems), improves audio fidelity, and is expected to reduce costs by roughly 60% once the legacy equipment is retired.

Metro Trains Melbourne

Marcus Morrison

Principle Software Engineer