For Newbies like me. What to study. This site for new people into voip and data communications in general is a great launching point to begin a journey that will give you great understanding and skills to proceed with voip systems. There is much more to study and my advice is read everything and more. If you don't recognized a acromyn then look it up. Leave nothing behind. One doesn't need to read and consume all the RFCs on every protocal and know there numbers but more so understand the protocal and where is sits in the models created to make this happen like the OSI and TPC/ip models. It is over kill to many as the vast communication network we live with is way more than the protocals used in pbxiaf. However to understand the forest you walk in is always good. I suggest if your not into geek stuff and you are just a good user in windows you should read the Introduction to Data Communications by Eugene Blanchard ( link on bottom left of Newbie page) and then refer to wiki for more info. After that you can look at the individual NOS programs and understand how they work. I am stretching the words here, however I believe it is a person's responsiblity to understand the large segment of communication going on in the human race and how it bears on life, freedoms and communications. Your path will surely help you on your computer network in security, where there it is figured to be 40 percent of us are either hijacked, monitered or being used for nefarious deals without our knowledge. You will know when you know enough to ask a question.