This would most likely be a pc or server external to the pbx. It would have a "bufferbox" connected to a serial output from the PBX. For example, I use VXtracker and can log on from anywhere within the network and see all collected call information, inbound/outbound calls, search by extension, number dialed, time of day, call type..etc etc etc....it also bills back departments for usage. All of this software would be separate from the PBX.