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USING RADAR AND VHF RADIO SIMULATORS ON A NETWORK

The Radar Simulators and VHF DSC Radio Simulators have the potential for communication over a network. This is only possible using Professional licences, and is an option you can choose each time the programs start. They can be networked, or run as independent stand-alone Simulators.

Networks can be wired, or wireless, but wired networks are more reliable and faster. General networking information is freely available on the web, but we will cover the basics below.

RADAR SIMULATOR

If you use the Radar Simulators on a network, one is installed as the Master or Instructor station. The others are installed as Slave or Student stations. The Instructor can then choose an exercise and control its running on all the student stations. Each student vessel is visible on the Instructor station, with its course and speed data.

Students can be configured in either of two styles. In the basic configuration, each student has their own, individual vessel within the shared exercise area. Each student is visible to the others, and can interact with them. All students also see the autonomous vessels, coastline, buoys and other details of the scenario. This is just the same as putting the students on a number of real vessels, these vessels may be of different types and students must take account of each other's actions and responses.

The alternative mode is for each student to start the exercise in an identical boat in the same position. The students cannot see each other, but all of them can see the rest of the objects in the exercise. With this mode, only the instructor can see how each student is navigating. Students are unaware of each others presence. On the instructor screen, the student boats will start as a stack in one place, then diverge as each applies their own logic and control to their vessel.

The Instructor can stop, start, or pause exercises, or move vessels and other objects around the exercise area. Weather conditions also can be changed. Some changes can be applied at any time, others will need the exercise to be halted while the change is made.

VHF DSC RADIO SIMULATOR

If you have two or more Professional licence VHF Simulators, you can connect them over a network and send any type of DSC alerts between stations, just as real life, but without the risk of prosecution for false alerts. There is also provision for transmitting voice messages across the network.

When the VHF Simulator is networked, one PC will become the Master or Instructor station and the others will be Slave or Student stations. When run in network mode, students will see their main radio and a GPS simulator, but they no longer have the remote station send/receive panels.

The Instructor has a main radio, plus a control panel through which they can assume the identity of any station - ship or shore. Multiple MMSIs can be pre-set and used at will. The Instructor also has a panel which logs every DSC alert which passes across the network.

Using networked Simulators, alongside the mandatory modified hardware radios, has many benefits, including: much lower cost; ease of sharing thanks to PC screens bigger than the physical sets; ability to display on a large screen via a data projector; coastguard and other shore-station working which is impossible on Class-D hardware; and GPS simulators which allow students to see when position and time data is sent. They learn that position is normally included in a distress alert automatically, otherwise they can go away thinking that they must enter the position manually if they have a distress situation, because that is all they have seen on the course.

For voice communication, a headset incorporating headphones and microphone is recommended. The network will impose a short delay in the speech transmission, like intercontinental phone calls, so if you use open microphones and loudspeakers, you may suffer from echo effects.

NETWORK HARDWARE

Nearly all PCs sold today have network capability. Most have a socket for an "ethernet" connector, whilst many laptops have wireless circuits built-in.

You can link two PCS, either wired or wirelessly, directly to each other. All networks of more than two PCs require a hub or switch through which they all communicate. If you wire two PCs together, you need a crossover cable, which links the send of one PC to the receive of the other, and vice versa.

HUBS and SWITCHES

A hub is a passive connecting box, with a series of sockets into which one end of the ethernet or patch cables are plugged. The other end of each cable is plugged into one of the PCs. When a hub is used, all communication on the network is at the speed of the slowest device.

A switch is similar to a hub, but has its own power supply, and allows different devices to run at their own best speed. Switches classed as 10/100 are generally fast enough for our Simulators, but if buying new units, we recommend you look for the faster gigabit switches to allow for future demands.

Hubs and switches come with varying numbers of ports or sockets. There is normally one more socket than the stated number of ports. The extra socket (the upstream port) allows for connection to another hub or switch to extend the number of networked PCs. We recommend using a switch, with enough ports to connect all your PCs to the one device.

ROUTERS

A router is essentially an interface between a PC or network and either another network, or the internet. It will have circuitry to help protect against unauthorised access from the outer network or internet. Most routers also incorporate a switch with four or more ports for PCs. If you use a wireless network, the switch will often be contained in a router, even if you do not require outside connectivity

ETHERNET CABLE

Network cables are supplied in two different forms. You can buy ready-made cables of various lengths, typically from 1 to 15 metres. These are known as patch cables, and come with plugs ready-fitted at each end. Alternatively you can buy a reel, or cut length of cable, plus separate plugs to fit. This form is generally cheaper and allows any length of cable, but requires time, knowledge and the correct tool to make up the leads. Some suppliers will make up cables to your chosen length. One other benefit of terminating your own cables is the ease of passing through walls, trunking or other obstructions, with no plug on the end. Fixed installations often use raw cable to link between wall or bench mounted sockets, then patch cables from the sockets to PCs.

CAT 5 or CAT 6

You will find references to cables as CAT or Category 5 or 6. For our software, the older, cheaper and thinner CAT 5 cable is fine. The newer CAT 6 specification allows faster data flow, but needs a gigabit switch and gigabit interfaces on the PCs to have the faster rate. If you anticipate other applications which need faster data transfer rates, then choose Cat 6 and gigabit hardware.