The hub is the National ANPR Data Centre (NADC), a data warehouse recently installed alongside the Police National Computer (PNC) in Hendon, London. The NADC will hold all number-plate data, along with ‘hot lists’ of suspect cars. Each ‘scan’ will generate four files: a text file detailing the car registration number, time and date of the scan, and the GPS location of the camera site; a JPEG image of the plate; a video image of the plate; and a video of the vehicle occupants. The NADC can store up to 35 million number-plate reads a day.
The NADC has been developed under an Oracle Real Applications Cluster, allowing multiple computers to access a single database simultaneously. It runs under Linux (from Redhat), and interfaces with web-based software that provides the national police access. A data-mining capability makes it possible to tell where a vehicle was in the past and where it is now, whether it was or was not at a particular location and the routes taken to and from those crime scenes. Anite and Civica are two of the main software suppliers for the system.
Data is fed into the NADC from the 43 police forces of England and Wales via their own ANPR servers (called BOFIIs), which connect to all ANPR cameras on their particular patch. From the point at which a vehicle passes an ANPR camera, it takes four seconds for a police intercept team to receive data on whether a vehicle is stolen, has been involved in a crime, or is under surveillance. During this time, the number plate is checked for matches against the PNC database and several other intelligence databases including Revenue and Customs, the DVLA and Motor Insurance databases, allowing officers to identify vehicles that are not registered, taxed, insured or are without a valid MOT.