Which ports open on the firewall for VoIP?
SIP on 5060 or 5061, RTP on a range. Too small a range causes drops under load.
Try this first
- 1SIP signalling: TCP/UDP 5060 or TLS 5061
- 2RTP media: UDP range 10000 to 20000 is common
- 3Outbound-only is usually enough, no inbound to open
- 4Range must be larger than twice the simultaneous call count
When to bring us in
Random drops when multiple calls? RTP range too small, expand it.
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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