Thank you everyone for your responses. To answer a few questions that were raised. This is in Australia. There are only two small offices in the one city of less than 30 people in total. It is a not for profit charitable organisation that helps people in crisis. As such they rely on donations to kee...

Hello, I only know a little bit about networks so please bear with me. I have two small sites that will soon have a VoIP service between them. That is, each site will have a VoIP gateway and use VoIP to talk to each other. They will not be using a 3rd party VoIP service. VoIP will not be used to mak...