What is an IP phone?
And when do you need it?

How does it work?

Voice is converted into data that travels over the same business network carrying the internet and the cameras, via the SIP protocol.

So each phone doesn't need its own line. Twenty employees can run on a handful of external lines, because the lines are shared by usage rather than by the number of devices.

What changes in practice?

Transferring between branches becomes internal and free of call charges. And a salesperson takes their number to any branch the moment they plug in their handset.

You also get what a traditional phone never offers: call recording, an auto-attendant that routes callers, and reports showing how many calls were missed and when.

When is it the right decision?

If you have more than one branch, a customer-service team, or you need to document calls — it's the right decision and it pays for itself within a year.

But a small office with a single line and three employees may not justify the cost. Don't buy a system just because its name sounds modern.

Its core requirement: a sound network

Voice is more sensitive to delay than any other kind of data. A congested network means a choppy call.

So you must have: a switch that supports QoS to give voice priority, a separate VLAN for the phones, and backup power — a power cut must not mean a phone outage.