I don't even know if this belongs here?. If not, do let me know.

So we have an analogue Alkatel PABX system in our little office. We have extensions, direct lines and PBX lines.

We are trying to move to a more digital/flexible way of handling the phones and I've heard good things about FreeSwitch. I have zero knowledge about it.

My biggest question is how would one handle existing phone lines with such a system. Surely there must be a way to make and receive calls from outside.

Just a help in the right direction would be fine.

Thanks.