You can find tons of useful information here: http://www.blackberry.com/products/e...on/index.shtml
To help you with that, here are few pointers:
- You will need to run separate server to host BES. It does not have to be heavy-duty server, just enough to run Windows 2000/2003 Server OS. New BES does not run on Windows desktop OS.
- You will need to buy BES software and CAL for each blackberry. It is possible that BES you buy could come with 5 to 10 CALs, more than enough for your four users.
- The benefit of BES is having seamless Calendar, Email, Notes, Tasks syncronization. Imagine Sunday evening your boss sending you meeting invite for Monday 8 am meeting. With BES that invite will be in your blackberry calendar immediately, and you would not have an excuse to miss the meeting.
Really, if your company can afford BES- go for it.
- You may have to pay a little extra every month to O2 and TIM to have blackberries enabled for BES. It depends on carrier, some do not charge extra, some do.
If you have BES and carrier has your blackberry enabled for BES you do not need anything extra for syncronization.
BES does not care which carrier blackberry belongs to. It should work for all your users, and for new users does not matter which carrier they sign with.