Moving to an IP PBX does not mean throwing away every analog phone and fax machine. An analog gateway connects them to the new system, so you upgrade the exchange first and replace handsets only when it makes sense. This guide explains how analog gateways work and how to set them up with Voxdial IP PBX.
What is an analog gateway?
An analog gateway is a small box with analog telephone ports on one side and a network port on the other. Each analog phone or fax plugs into a port, and the gateway registers that port to the IP PBX as an extension. To the PBX, an analog phone looks like any other extension.
FXS and FXO in plain words
| Port type | Connects to | Use |
|---|---|---|
| FXS | Analog phones, fax machines, door phones | Keep existing handsets as extensions |
| FXO | Analog lines from a telephone operator | Bring old landlines into the IP PBX |
This guide focuses on connecting analog phones (FXS). For phone lines, read SIP trunks and PRI to SIP migration.
Where analog gateways help
- Large sites with old cabling: factories, hospitals, hostels and campuses where re-cabling every room is costly.
- Fax machines still used by some departments.
- Rooms that need simple, robust phones: wards, store rooms, security cabins.
- Phased migration: replace the exchange now, phones later.
Setting up a gateway in Voxdial
- Add the gateway: name, MAC address, vendor and model. The model sets the number of ports.
- Map ports to extensions: pick an extension for each port; the port switches on automatically.
- Generate and push the configuration to the gateway.
- Check the deployment map: each analog port appears with its extension and registration status.
Gateways found by the network discovery scan are added to the gateway list automatically. BitVoice analog gateways are auto provisioned by Voxdial the same way as IP phones, so nothing is typed into the gateway itself. See IP phone auto provisioning.
Managing gateways day to day
- Resync re-fetches the configuration without a reboot, so calls are not dropped.
- Reboot restarts the gateway; active calls on it end, so do it out of hours.
- Change the web password: gateways often ship with default admin passwords. Change it from Voxdial, which keeps the stored credentials in step.
- One extension, one port: an extension can be mapped to only one port on one gateway.
Tips for a smooth migration
- Label each analog port and cable with its extension number.
- Change default gateway passwords on day one.
- Keep a spare gateway for critical areas.
- Plan to replace analog phones with IP phones where users need features such as a display, voicemail light or many line keys.
BitVoice plans and installs gateways as part of EPABX to IP PBX migrations. Book a site survey.
FAQs
Can I use analog phones with an IP PBX?
Yes. An analog gateway with FXS ports connects analog phones and fax machines, and each port registers to the IP PBX as an extension.
What is the difference between FXS and FXO?
FXS ports connect analog phones and fax machines. FXO ports connect analog phone lines from a telephone operator.
Does rebooting a gateway drop calls?
Yes, calls on that gateway end during a reboot. In Voxdial, a resync updates the configuration without rebooting.
How many analog phones can one gateway connect?
It depends on the model; gateways come with different numbers of ports, and Voxdial reads the port count from the model you select.
