# DMR Networks

Within the previous sections, I tried to outline the concepts and some technical details of a DMR network and how a codeplug might be assembled. These concepts, however, apply only to the so-called Brandmeister network. This is the network in the background that routes your private and group calls, connects repeaters etc. In Germany, this is the dominant network. But also world wide, it connects the majority of repeaters (about 5000). However, there are also other networks. There is the DMR-MARC network and the DMR+ network. Which network you are likely to encounter, depends on your location. In countries like France, Spain, BeNeLux, Poland, Czech Republic and Slovakia, almost all repeaters are connected to the Brandmeister network, while in Denmark the DMR+ network dominates. In the USA and Austria, DMR-MARC repeaters aren't rare. All these networks do not differ on the technical level. That is, you DMR-ID is valid in all of these networks and you can use any DMR Tier II radio.

The concepts however, in particular how group calls are performed, depends heavily on the network. This means, that you need to configure the repeater channels for a DMR+ repeater in a different way compared to a Brandmeister repeater.

Reflectors play an important role in the DMR+ network. They represent a talk group within the DMR+ network.

The major difference between a reflector and a talk group is, that they cannot be simply called using a group call. They are subscribed to a local repeater by a private call to the reflector. Then all repeaters subscribed to that reflector behave like a single repeater. You will then participate on that reflector by performing a group call to TG9, the local talk group. Your call will then be sent to the reflector as well as to all other reflectors currently subscribed on the repeater and consequently to all repeaters also subscribed to that reflector.

This has the advantage of a much simpler codeplug assembly, as only two channels are configured for each repeater. One for each time slot. The default transmit contact will always be the local talk group TG9. To subscribe a reflector, a private call is started to the reflector from the contact list. This implies that the contact list should contain all reflectors you are interested in. This concept is also much closer to the semi-analog concepts of EchoLink. However, advanced features like roaming are not possible this way. Also the repeater transparency gets lost. Instead of simply starting a group call to the destination talk group, the local repeater needs to be configured. Once that configuration is done, the communication will happen on the local talk group TG9, even if the communication is not local anymore.