How to organize SIP for taxi service?

Question

Telephony

Gentlemen, I don't understand much about telephony, but it's up to me to solve the problem. In general, there is some navigation program, it is tied to SIP. The taxi should receive calls from the landline and cellular, then go to the program itself. It is clear that cellular communication and analog line are different technologies and they require different devices. How can I implement SIP telephony? The organization does not have an automatic telephone exchange, and cannot afford an expensive one. The load is not large, there should be 2-3 lines that will be loaded, and this is not a fact, on holidays. A friend advised such a device: shop.nag.ru/catalog/02601.VoIP-i-Telefoniya/08331....If I understand correctly, the setup process goes like this: I rent a SIP server from a provider, they give me connection data. This PBX includes an analog line, and when you call, it is converted into a packet form and sent to the provider's server and returned to me at the PBX using the SIP protocol, but then to the program? The same thing needs to be done with GSM, here I have no idea what is needed.
There is no possibility to use your own provider, in particular Rostelecom, because the Internet is from the beeline. Beeline stopped providing SIP services. Redirecting calls directly to the server is a little expensive because long-distance. I do not understand this, and therefore I ask you not to laugh. Advise how to be in such situation. What's the best way to do it? Finding a knowledgeable person is not an option, the city is small. Thanks in advance.

Answer 1

A friend advised such a device: shop.nag.ru/catalog/02601.VoIP-i-Telefoniya/08331.... If I understand correctly, the setup process goes like this: I rent a SIP server from a provider, they give me data on connection. This PBX includes an analog line, and when you call, it is converted into a packet form and sent to the provider's server and returned to me at the PBX using the SIP protocol, but then to the program?

Not true. Judging by the description, this device includes Asterisk which is the SIP server. No need to rent anything else :)
Your task should be divided into three tasks
1. Receive calls from a landline
2. Receive calls from a cell phone.
3. The organization of internal automatic telephone exchange
IP automatic telephone exchange which advised you solves 1 and 3 tasks.
There are two options for receiving calls from a cell phone
1. Use Megafon (with their Multiphone service)
2. Buy a GSM VOIP gateway and insert a SIM card or SIM cards depending on your needs.
there are gateways from 1 to 32 ports (simoks). I am using GOIP gateways.

Answer 2

SIP should receive calls from landline and cellular, then go to the program itself - "WHAT?".
It will not work for free:
a) You have to pay for communication;
b) clients (programs, phones) must receive calls. They cost money (as a rule, a computer also has a headset for it)
c) the Internet costs money;
d) A modem for SIM cards costs money (the megaphone has a Multifon solution - it is Sipov's to the megaphone number)
I would recommend budgeting 30 thousand for a solution based on a "server" (2GB RAM, HDD 1TB, CPU Pentium|core i3).

The taxi should receive calls from the landline and cellular, then go to the program itself.

Have you heard of freelancers? Cloud servers (cloud.google, azure, digitalocean, etc.)?
I will recommend Zadarma or Mangosip to you. They have the opportunity to take off a "cloud PBX" for a subscriber. You do not need to buy anything, except for client phones. You can also pull any CRM (program) from there.

Answer 3

If you do not understand telephony from the word at all, it is better to hire a specialist who will solve this problem for you.
The first and main question is what does it mean "then enter the program itself", from the answer to this question envy the range of solutions that can be used.
If by entering the program it is meant that the program has a built-in softphone, then there are two options, the first is to rent a virtual PBX from a service provider, some of them can be linked to a gsm number (either virtual or real from a megaphone, other operators have similar services, but they are complex). The second is to buy our own IP PBX, we use a grandtream piece of hardware that is quite simple to set up and quite reliable, plus a gsm gateway or a multiphone from a megaphone, a gsm gateway can be taken with goip (extremely inconvenient to set up, but stable enough) or yeastar (much easier in setup, but once a month you have to reboot).