In a previous note I suggested that AXS-One, Sun and BT were supplying the UK Police with technology to access, search and store records of vehicle locations from a network of some 3000 ANPRs - automated numberplate recognition cameras.

This was based on AXS-One software having the search speed required and Sun being a strategic partner of AXS-One. In fact the actual hardware and software comes from Dell, EMC and Oracle. The networking comes from Cable and Wireless. You might think I couldn't have got it more wrong. I couldn't possibly comment.

Here is the description of the system that Frank Whitely, a Hertfordshire police chief involved with it, sent me:-


The National ANPR Data Centre (NADC) will consist of a Primary System located at PNC Hendon and a Disaster Recovery Site at an undisclosed location. The NADC has been developed to be fully redundant with complete load balancing and automatic failover functionality. The system will have the capacity to initially support 35 million ANPR ‘reads’ per day, and will provide real time matching of vehicles of interest to law enforcement agencies.

ANPR data will be received from all UK Police Forces with matches against the NADC being returned to users approximately 5 seconds after a vehicle of interest has passed an ANPR camera.

Data will be stored on NADC for a period of up to 2 years, which will allow extensive post-incident searching capability. NADC will also provide Forces with comprehensive data mining functionality.

Disc storage capacity of approximately 47 Terabytes will initially be provided through a combination of Dell’s DAE2 drive arrays and EMC Centera hardware. NADC is fully expandable and storage will be increased in line with the anticipated growth in ANPR technology deployment across UK.

NADC runs under the Linux / Redhat operating system. .

The core NADC data warehouse has been developed under an Oracle 10g RAC which interfaces with bespoke web services application software allowing national police access. Connectivity to NADC will be via the CJX, the secure national network of the Police Service.

As with all national police systems the NADC will be centrally controlled and fully audited.

The CJX network
According UK PITO (Police IT Organisation) web pages: "PNN2, the second generation Police National Network, is the telecommunications infrastructure the UK police service uses. It provides forces with telephony, internet access and a secure extranet – the Criminal Justice Extranet (CJX). PITO signed a five year framework contract for the services with supplier Cable and Wireless in September 1999 and the new network went live a year later. The contract has since been extended to 2006."

Dell DAE2 drive arrays
These are Dell-supplied EMC Clariion CX drive arrays. There is a 2Gbit disk-array enclosure) that uses a Fibre Channel Arbitrated Loop (FC-AL) as its interconnect interface. An enclosure connects to another DAE2 or a storage processor, and is managed as a RAID (Redundant Array of Independent Disk) configuration. The enclosure, 3U (5.25 inches) high, can include 15 3.5 inch hard disk drive modules linked by FC-AL. The system can provide additional disk storage as needs increase.

You can interconnect up to eight DAE2s to Fibre Channel loops (sometimes called busses) to form a larger disk storage system. The number of loops depends on the capabilities of your storage processor; highly available configurations require at least two loops, other configurations use a single loop. The disk enclosures can be placed in the same cabinet, or in one or more separate cabinets.

Considerations
Oracle clustering on Dell hard servers with Dell (EMC) drives and Red Hat Linux is a triumph of commodity hardware, open source operating software and clever software. The use of Centera, probably for the storage of individual vehicle records up to two years seems to the point. We calculated that there could be 25.5 billion records after two years. Storing them in Centera using content addressing should allow a high degree of compression through de-duping elements of the records.

Whatever one thinks about the ethics and possible civil liberty infringement involved in this system the technology behind it is impressive. There's a Techworld Forum comment on this story here.