“Security is, of course, a huge issue in this network – so we would still keep at least a controlling hand on the steering wheel.” Controlling the control roomsOne aspect of the programme which proved unexpectedly time-consuming was that of specifying control rooms for the various agencies. To be supplied by Frequentis, these will range from large centres for the main agencies down to a host of smaller ones in the health service, including local response centres and doctors on call. “That’s taken a lot of attention from us”, says Dagfinn Sjøvik, project manager for Nødnett. “Just clarifying the scope of what is relevant for a big project and what is third-party applications for the end users – where do you draw the line? What’s in the project, what’s outside the project? From the technical point of view, it creates discussions on the interfacing: who is responsible. And that increases risk to the overall project as well, because technically it needs to work. “Technical issues are only half the story of this. In order to get a good public safety network to work, you also need to work on the operational procedures in the background here – on the control room, on the terminal side. And the more you add of technical solutions in the control room, the more you dig into the operational procedure domain of the end users. “Say you want to go live with an agency: the more you add, the more risk you put into it. Then there’s something initially not linked to the main project that keeps you from starting using the whole service. “We also need to respect that the service we bring in here is a part of a bigger chain of emergency handling of agencies, so what seems to be a clear line for us – this is inside their contract, if you will, and this is outside their contract – if you put on a police hat or an ambulance hat, he doesn’t see the same clear border.” Calling out Norway’s volunteer firefightersA TETRA development which has been pioneered in Norway is a function known as callout. “You send an alarm message out, typically to volunteer firefighters who are not based in any fire station”, explains Dagfinn Sjøvik, project manager for Nødnett. “So we are replacing the pager functionality of today. “With this functionality, they will be able to not only get the beep in their phone but also get their voice message, and they can reply back, ‘I’m coming’ or ‘I’m not coming’. And of course that, on the control room side, enables a better utilization of the resources. They know who is coming, who is bringing what gear and stuff like that. This is implemented in ordinary radios and it has also been through the TETRA specification process.” It’s expected that the volunteers would much prefer to carry a small TETRA pager which has a long battery life, in place of a bulkier radio – although, as a pocket device without an external antenna, a TETRA pager might lack sensitivity. “We always get a question about, ‘Is the coverage good enough?’?”, responds Tor Helge Lyngstøl, director of DNK. “But we have some special planning for this. We have a stronger field strength in the distance up to 5?km from all the fire stations for these voluntary firefighters. They will be within that range.” Conveniently, most houses in the Norwegian countryside are made of wood, which is more transparent to radio signals than most other building materials. Analysing the benefitsMarianne Storrøsten, a specialist in user psychology, has been involved extensively in evaluation of the network and many aspects of its planning, both within government and now at DNK itself. These evaluations formed part of the case for proceeding to a national deployment. Her work also guides decisions on how to manage the network during major incidents, events such as the July 22 outrages. “What can we do as an owner of the infrastructure?”, she asks. “Should we be there much more? And when should we come in with repeaters and such things, and also come in and give advice on efficient use of talkgroups? There are so many different settings and ways to use it. “Some things take a lot of capacity, others don’t – just like when you have teams coming from outside Oslo to help. If they bring a radio with their own talkgroups, they will steal capacity. And especially if you take an Oslo talkgroup out to smaller districts, that will kill the capacity right away. So we can tell how it works and then we can ask the questions. We cannot say that you are not allowed to do it!” (中国集群通信网 | 责任编辑:陈晓亮) |