CCTV at a leisure park

A leisure park covers several hectares, with no walls and no service ducts through which to run cables. It is precisely this kind of site that forces you to rethink the way a video-surveillance installation is designed.

The project carried out in the municipality of Messein illustrates the point well: the layout of the site made it impossible to install a data transport network for every camera. It was therefore agreed that four recorders driving six cameras could be installed, and at a lower cost. These recorders were connected to the telecoms network of the municipal buildings, and they are consulted remotely, through an application installed on PC and on mobile phone.

Why a leisure park complicates a video-surveillance project

In an office or a workshop, installing a camera often comes down to running a network cable from an existing rack. The route is short, protected, and the electrical supply generally travels alongside the data on the same cable. None of that can be taken for granted on an open-air site.

Long distances, and few cable routes

On open ground, the points to be monitored are scattered: entrances, car parks, technical buildings, the edges of a body of water. Linking each of them to a central point means digging trenches, laying ducts, and sometimes crossing areas that cannot be opened up. The civil engineering cost then quickly exceeds that of the surveillance equipment itself.

On top of this come the usual technical limits: beyond a certain distance, a copper link no longer holds, and you have to move to optical fibre or a wireless link, with the alignment and maintenance constraints that this entails. Each solution has its place, but none of them is free.

What is really at stake for the operator

Before talking about cameras, you need to know what the images will be used for. Deterring vandalism, documenting an incident, checking remotely whether something is actually happening before sending someone on site: these are not the same needs, and they do not call for the same means. An oversized installation is expensive to fit and to maintain; a badly positioned one will be of no use on the day you need it.

It is also a matter of liability. Filming a space used by the public commits the operator on signage, on how long images are kept and on who is authorised to view them. These rules vary according to the country and the type of location: they should be checked before the project begins, not at the time of installation.

The approach chosen at Messein: four recorders for six cameras

Rather than bringing every camera back to a single point, the installation was divided up. Four recorders were distributed across the site, each one driving the cameras located in its immediate vicinity. The links therefore remain short and local, and the question of a long-distance network largely disappears.

What this distribution changes in practice

• Less construction work: cables no longer have to cross the site from one end to the other, which reduces the need for trenching and ducting accordingly.

• A contained overall cost: