Which piece of iron sip-gsm to choose?

Question

linux

Greetings,
There was a question about connecting mobile numbers to the PBX, I wanted to take goip4 as always, but the customer cuts the money.
To be honest, I have little idea what could be cheaper, but suddenly someone knows a good, stable solution.
Requirements:
Call in both directions, hold the call, be able to use the simplest codecs,

Answer 1

And Multifon from Megafon will not work? It is immediately available via SIP ...
Here is an instruction even for setting up: multifon.ru/media/devices/instruction/Asterisk_set...

Answer 2

you can hack through analog GSM gateways + gateways with FXO ports
whether it will cost less another question, but do
n’t be fooled by the problems of adding 3G modems for sure - this is only for home use
Who is stopping him from cutting off your reward for the work done?

Answer 3

Much cheaper than GoIP... Taking sip
-trunks from providers is not an option?
If not, and discard all sorts of crutches of scripts that reset modems in managed USB switches, then there is only one option - to take a used one.
Well, for good luck, you can ask about the prices for OpenVOX. Sometimes, due to the popularity of GoIP, Openvoxes are even sold a little cheaper, despite the fact that the latter are of better quality.

Answer 4

I use asterisk+chan_dongle 17 phones\modems
very flexible. flight normal for 2 years.