Migrate an existing ISDN PBX to all-IP cleanly.
Two paths: keep the old PBX with an ISDN-to-SIP gateway, or replace it with a cloud PBX. For a 5+ year-old PBX, replacing is usually cheaper than patching.
Try this first
- 1List PBX age, support contract and feature requirements.
- 2Gateway path: SIP trunk and a gateway box (Patton, AudioCodes) to keep old phones alive.
- 3Replace path: pick a cloud PBX, phase phone replacement to SIP handsets.
- 4Port numbers to the SIP trunk or cloud PBX, otherwise you have a gateway but no route.
When to bring us in
PBX has custom call flows, DECT or integrations: replacement requires redesign, scope that before fixing a date.
See also
- Voys, BelXS or RoutIT, which cloud PBX fits?Three popular NL platforms, differences are admin UI, partner model and per-user price.
- Teams Phone: Calling Plan, Direct Routing or Operator Connect?Three ways to connect PSTN to Teams, cost and management differ a lot.
- 3CX: self-host on VPS or take 3CX cloud?Self-host saves licence, but you own SBC, backup and updates.
None of the above fits?
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Or skip the DIY entirely
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