IP telephony and use of the old city number?

Question

Asterisk

It is necessary to deploy ip telephony in the enterprise and at the same time keep 4 old city numbers, respectively, to save money (for the sake of which everything is started), you need to configure incoming calls to go to old city numbers (since they have been with clients in contacts for many years) and an incoming call will be free, and outgoing long distance calls went through ip telephony, but calls within the city went through analog telephony. also outgoing to cellular went through ip.

Answer 1

I believe that this is a completely typical task.
SoftPBX needs to be deployed, such as Asterisk. (Better without any Web add-ons - it will be easier to configure.)
Solve the issue with subscriber terminals - either use old telephone sets using an FXS gateway of the required dimension (which is not very good), or purchase SIP phones and connect them to the local network ( which is a little more expensive, but then thank yourself forty times).
Somehow ground this city capacity of yours - for example, install a four-port FXO gateway. It must be selected taking into account the mores of your city PBX.
Arrange with the VoIP operator to terminate calls through it. You have to look at prices and conditions.
By the way, it is possible to buy an incoming VoIP number may be cheaper than paying GATS its tariff.
Paint the dialplan, taking into account the logic, the cat. You called.
Actually everything...

Answer 2

IMHO it is easier to unconditionally redirect analog lines to ip-telephony than to suffer with the work of FXO. Everything else - as advised above.

Answer 3

I meant whether it is possible to implement this and through what is easier for a beginner in these matters.

Answer 4

Yes, well, you scare a person,
especially please put an aster without a web muzzle - break your fingers, drip into your eyes.
Find in the city, for example Grandstream UCM6104, the cost of the station is about $500-600, buy the required number of IP phones and go. The interface is intuitive, you will figure it out in a week.

Answer 5

Is it possible to use the old DIAL-UP modem instead of the FXO gateway for the city line? I read somewhere that it is possible and even what modems are supported, but maybe someone will throw a config. modem on INTEL 537 chip