I don’t understand anything in telephony, which phone to buy?

Question

Telephony

Good morning. There is an Eltex SMG-200 station, VP-12 phones were purchased with it. But now I needed to buy new ones and I don’t even know what to write in the TOR.
Does each station fit only certain phone models? Can I describe specific models in the TOR, substantiating all this with narrow compatibility with current equipment? Or is any VoIP phone suitable and you have to describe the parameters?

Answer 1

Judging by the description of the station, any IP-phone with SIP support is suitable.

Answer 2

Such questions are not here, but the manufacturer of the automatic telephone exchange should be clarified.
Ask them for a list of compatible phones and stick to it.
And even better - when buying a batch of phones - test on one unit.
The SIP standard - of course it is a standard - but with a specific phone model, you can easily get into trouble.

Answer 3

I don’t know anything about the Eltex SMG-200, but from experience I can say that sometimes not everything is obvious and it’s better to consult someone who knows exactly about this station, for example, from a supplier.
For example, for the LG station, you can buy their phones on their protocol (they are also sip) and they will work right away, or you can just buy a sip phone, but then you still need to buy a sip license. And here it is already necessary to look at what is more profitable.