This is my setup of my home ip phone a Panasonic KX-NT321 connecting to a Panasonic NCP500 using Mikrotik routers with site to site ipsec vpn.
This allows me to receive calls from the office without being there and also place calls using the main office telephone number.
Great for remote workers as you can transfer calls between remote works from home to workers in an office. Call both ways for free for internal calls as well.
Still the most secure way to connect a remote phone as we are not exposing PBX to ports having to be opened on a firewall.
Create the ipsec vpn with the mikrotik routers, which is compared to buying off the shlef vpn routers a really cheap way of creating the ipsec connection.
Of course normal prices apply to panasonic equipment.
This could be programmed to be part of a hunt group or groups etc, you simply treat it as an office phone extension, you can programme BLf (busy lamp field) to, that will enable you to see if co-workers are on the phone or not.
