A method of processing communication session data from a mobile radio communications network, the method comprising: extracting, by a device, communication session data relating to all calls in at least two sectors of the mobile radio communications network over a time period, as the communication session data becomes available, thereby providing a stream of communication session data, the communication session data including information identified based on a communication session between a first mobile communication unit and a second mobile communication unit; creating, by the device and from the stream of communication session data, a high priority data stream comprising a minority of the communication session data, the high priority data stream including communication session data for each call included in all calls in the at least two sectors of the mobile radio communication network over the time period; processing, by the device, the high priority data stream to produce geolocation data for each call included in all calls in the at least two sectors of the mobile radio communication network over the time period; storing, by the device, the high priority data stream and the geolocation data in a storage area that is smaller than a memory necessary to store the stream of communication session data; providing, by the device, an immediately accessible copy of both the high priority data stream and the geolocation data for each call from the storage area; and deleting, by the device, the communication session data based on storing the high priority data stream and the geolocation data. extracting, by a device, communication session data relating to all calls in at least two sectors of the mobile radio communications network over a time period, as the communication session data becomes available, thereby providing a stream of communication session data, the communication session data including information identified based on a communication session between a first mobile communication unit and a second mobile communication unit; the communication session data including information identified based on a communication session between a first mobile communication unit and a second mobile communication unit; creating, by the device and from the stream of communication session data, a high priority data stream comprising a minority of the communication session data, the high priority data stream including communication session data for each call included in all calls in the at least two sectors of the mobile radio communication network over the time period; the high priority data stream including communication session data for each call included in all calls in the at least two sectors of the mobile radio communication network over the time period; processing, by the device, the high priority data stream to produce geolocation data for each call included in all calls in the at least two sectors of the mobile radio communication network over the time period; storing, by the device, the high priority data stream and the geolocation data in a storage area that is smaller than a memory necessary to store the stream of communication session data; providing, by the device, an immediately accessible copy of both the high priority data stream and the geolocation data for each call from the storage area; and deleting, by the device, the communication session data based on storing the high priority data stream and the geolocation data.