Question about telephone service for a small business?

I'd appreciate an answer to this or if you can direct me to any site that deals with this it would be great too. I've got a small business of about 40 people and I want to install a telephone system such that people from outside would call a single number and my machine would ask for an extension to connect them to the person they're calling. I'm thinking of using Asterisk for this, but my question is, what do I actually need to get from the phone company? 40-50 telephone lines? or is that what they call T1, T3, etc? I just want to be better informed so when the time comes to talk to the phone company I can make an informed decision. Thanks guys.

Now i am no expert at this but i did have to do a lot of research for myself when i was getting a phone system. You do not need 40-50 lines. Thank goodness. If you did that would be crazy!!! What you do need to do is figure out how many lines you think your employees will use at one time. And how many extensions you will need. Sounds like 50. What you have got to realize is a phone system takes advantage of having multiple lines. When your employees are using the phone not all of them are using it at the same time. They will use it for a certain time frame and hang up. Having a telephone system allows you to use fewer lines with more extensions. It allows the extensions to share them. So you might be able to get away with 15 lines or more. This is kinda a guessing game you don't want to have to little as someone will have to wait to use the phone but you don't want to have to many either because there will be some not even used.

http://www.buyerzone.com/telecom_equipme...

This site will allow you to create a quote query that will go out to multiple companies and they will call you. Most of them are very knowledgeable and can guide you more directly. As for the T1 line you really don't need that either unless you are going Voice over ip and if you are going to be doing a lot of long distance it might be something you would like to look into. It is much cheaper to maintain. But as far as that goes Business DSL is faster than T1's just not as well serviced. DSL lines will travel up to 6mbps now compared to a T1's 1.5mbps. Hope this helps i can explain in more detail if you want. But there are a number of sites out there devoted to explaining phone systems.