Telematics Technology's Peter Billington describes the effort to give English local authorities and police forces a UTMC ANPR open communication protocol. The story of the impact of communication protocols on the development and utilisation of intelligent equipment is a familiar one both inside and outside the ITS industry. At the outset, a company pioneering its latest technology invariably develops a proprietary protocol. This enables the company's products to talk to the customer systems which need to a
The story of the impact of communication protocols on the development and utilisation of intelligent equipment is a familiar one both inside and outside the ITS industry.
At the outset, a company pioneering its latest technology invariably develops a proprietary protocol. This enables the company's products to talk to the customer systems which need to assimilate the new type of data in order to realise the benefits the new technology offers.
Generally, this is a good thing. Proprietary protocols are technology enablers, allowing end users to benefit from the early introduction of ground-breaking equipment and applications, and suppliers to profit from their good ideas, hard work and investment.
It is not difficult to imagine the impact on progress if a committee had to be convened somehow to draw up an open standard for a yet-to-be-deployed new technology; where would the Internet be today if Kahn and Cerf had not just gone ahead and created TCP/IP? However as a new technology becomes established and the early pioneers are faced with or even overtaken by competition, proprietary protocols become restrictive. Manufacturers use them to maintain their competitive advantage once third-party applications have evolved around them.
The investment in third-party software development can be an obstacle to competing players as the cost of introducing their equipment may also entail expensive redevelopment of central system applications. This can also stifle further innovation, as systems which have grown up around the capabilities of first-generation technology and its associated proprietary protocols can be limited in their ability to utilise the enhanced capabilities of second-generation developments.
Becoming more open
At this point, end customers (perhaps by now feeling they are being held to ransom by the established supplier) start to raise their voices, demanding that an open protocol and interoperability, that Holy Grail, give them freedom of choice and the lower prices which a more competitive marketplace confers. A resounding cheer can often be heard from the newer suppliers, who perceive the opportunity to break the monopoly of the incumbents.However, to create an open protocol requires a good deal of effort and determination, usually requiring cooperation between competing suppliers and encouragement (or even coercion) by their customers. One part of the ITS industry in the UK is fortunate in having a public body (UTMC), set up in 1997 by the
Traffic management with ANPR
Whilst an established tool for law enforcement, it is only comparatively recently that Automatic Number Plate Recognition (ANPR) has gained ground as a local authority traffic management tool, primarily as the detector of choice for journey time measurement and congestion detection systems. This use for ANPR technology was showcased early in the new millennium by the HA's National Traffic Control Centre (NTCC), which has established a journey time measurement network covering all of England's motorways and trunk roads.Many of the local authority ANPR-based journey time measurement systems established during the last decade have been coupled into their UTMC in-stations, at the core of which is a UTMC Common DataBase (CDB). Although journey time measurement software has evolved which delivers data into the CDB at the output side, the inputs from ANPR cameras have until very recently used only manufacturers' proprietary protocols.
Understandably, being used to much of their other outstation equipment (such as loop counters and variable message signs) having a UTMC-standard interface, end users wished to have the same advantages of freedom of choice of supplier and a more competitive marketplace where ANPR systems were concerned. Accordingly, the
Expanding horizons
At around the same time, the first initiatives were being established which involved cooperation between public bodies in sharing what is typically quite costly ANPR equipment. As well as avoiding the nonsensical situation where multiple ANPR cameras belonging to different bodies are pointed at the same lane of traffic, the sharing of equipment not only gains approval from the taxpayer but also gives the cooperating parties greatly increased coverage for the same budget.Local authorities and their counterpart police forces have been the first organisations to reap the rewards of sharing equipment. In addition to the obvious savings from the elimination of duplicated installations, cooperative projects have been found to further improve value for money, reducing both the price of equipment bought in larger volumes and overheads in terms of procurement, project management and administration.
In order to achieve all the good things an open protocol should deliver, it was obvious to the ANPR Working Group that it needed to extend its horizon beyond the usual UTMC confines of traffic management applications. If ANPR equipment was genuinely to be interoperable, the protocol had to deliver the information needed by all parties who might be involved in sharing the equipment. In particular, police applications have requirements for the capture and delivery of images the like of which have never featured in traffic management operations.
To this end,
Gaining acceptance
The Working Group was also conscious that to be successful (in other words, for the protocol to be offered by suppliers and specified by users) it should be straightforward to implement. The UTMC SSG supported the ANPR group in moving away from the traditional use of an SNMP (Simple Network Management Protocol) framework to an implementation using XML web services - as the name implies, a software technology developed around internet applications which is very flexible and fast to implement using the latest-generation software development tools.Furthermore, since XML web services are designed for delivery via TCP/IP, UTMC ANPR systems can communicate via a plethora of readily available networks - GPRS, 3G, WiFi, ADSL and Ethernet can all be used without the need for software changes. Provision for SSL encryption even allows use of the public internet. Five years ago, the use of XML web services would have been ruled out due to the bandwidth requirement and the costs of transmission over cellular networks. However, the recent escalations in available bandwidths and plummeting costs of data have made them the obvious choice for connecting today's applications.
A protocol for mobile applications
Increasing use is being made of mobile ANPR cameras. Local authority traffic engineers conduct temporary journey time and origin-destination surveys using battery-powered cameras either simply mounted on tripods (for surveys of a few days in duration) or on brackets strapped to streetlight columns for longer projects.
ANPR cameras mounted on police vehicles are obviously highly mobile, and re-deployable cameras are used for targeted surveillance operations, again often fixed to street furniture or in more discreet locations. In many of these applications, wireless communications (usually GPRS or 3G) are invaluable, as it is unlikely that there will be a handy wired Ethernet or broadband connection in most temporary locations. Being IP-based, the UTMC ANPR protocol is ideal for use over mobile cellular networks and incorporates features to allow the amount of data transmitted to be tailored to the available bandwidth. Highly useful in mobile applications, a GPS unit embedded in the camera automatically records the location at which a camera is operating and also provides an accurate time reference both for time-stamping plate reads and for recording when a camera was deployed at a particular location. The UTMC ANPR protocol provides for latitude and longitude co-ordinates to be attached to every single plate read, so an accurate time-stamp and location is known for every vehicle captured, and can be available at the in-station within a few seconds of a vehicle passing the camera.
Web-based protocol
Not having to concern itself with any SNMP legacy systems, the ANPR protocol is the first based entirely on web services to be published by UTMC, and was released in December 2009. Since then, almost every local authority tender for ANPR has specified the protocol, and the first system, using Evo8 cameras supplied by CA Traffic, where the UTMC protocol is delivering data from shared ANPR cameras simultaneously to the police and to a local authority is currently being installed in the UK by Buckinghamshire County Council.Future ambitions
Looking forward, the HA has announced that UTMC is to become a cornerstone of its Technology Convergence Programme, and that in future UTMC protocols will be used for both internal and external links to its Regional Control Centres (the seven traffic management centres which, between them, control England's strategic road network). One of the key benefits seen by the HA will be the ability to share information and collaborate with local authorities much more efficiently, especially in the management of incidents.Looking further ahead, both UTMC and the HA are supporting the EU ITS Action Plan and Directive which aim to develop Europe-wide specifications for ITS. Having been, to date, almost entirely UK-centric, this will require UTMC to look outward and align with European initiatives such as DATEX II. The ANPR protocol might be seen as a first step in this direction, having in common with DATEX II a foundation built on XML web services. Could the UTMC protocol become the first European ANPR open standard? The possibility at least is an appealing thought.
