NXDN™ contains two trunking protocols within the same standards suite. For the purpose of simplicity these two trunking protocols have been called NXDN™ Type-C and NXDN™ Type-D trunking.
Type-C trunking is a centralized, control channel based architecture where the trunking logic and allocation of traffic channels is done via a dedicated control channel.
Type-D trunking is a distributed logic based architecture where no control channel is used, and all channels available in the system can operate as traffic channels.
As the NXDN™ standard contains a broad spectrum of functions, the feature set of a system is determined by the manufacturer developing their system for the market needs they will serve. There are mandatory and optional features defined in the standard here, but the following could be considered to be common to most NXDN™ trunking systems of either variety.
- Single and Multi-site capability
- Individual and Group call capability
- Data features (Short text, GPS and status messaging)
- Automatic Roaming
- Maximum of 60,000 ID's per system
- Wide area networking capability via IP linking