Network Architecture advice appreciated

Hello all, this is my first post and obviously I’m a newb. I’m trying to setup a network similar to the following diagram. Basically I have two static IP’s, one is for the PBX and the one is for the LAN for VPN purposes. I don’t want the PBX to speak with the rest of the network except for softphone access on some desktops/laptops only.

http ://4lph40m3g4.com/files/public-docs/1.png

This is my first network setup and any tips, recommendations or advice would be really appreciated! :smile:

Thanks a million!!