What is happening
Operators worldwide are retiring the traditional public switched telephone network and ISDN in favour of IP. Once a line is withdrawn, services that depend on it must already have moved to an IP-based alternative such as SIP trunking or hosted voice.
How to plan the migration
- Audit every line, number and device that relies on ISDN or PSTN.
- Port existing numbers to a SIP provider to keep them.
- Choose SIP trunking or hosted voice to match your platform.
- Test in parallel before cutting over, then decommission legacy lines.
What you gain
Beyond compliance with the switch-off, IP voice brings elastic capacity, lower line costs, geo-redundancy and the ability to consolidate international numbers with a single provider.