Atcomm have an on line service, they store all the records etc, all you have to do is provide a PC (nothing special) to send (FTP)the info to their site. You get multiple log ins to a website where you can run reports. You can specify any or all extensions, so you do not have to waste money for phones you do not need to monitor. They set up all the software, you just plug in the PC and set up the CDR stream from the PBX to it. It is a yearly expense, but gets you away from paying for upgrades to internal sotware etc. Very easy to use. If you have multiple sites, with different PBX/IP Manufacturers, they can roll all CDR in to one tool. I am sure there are other such services out there too.