MOTOTRBO: What does MNIS do?

MNIS (MOTOTRBO Network Interface Service) is a Windows service application which supports
data between PC-based applications and MOTOTRBO radios. It would be used in systems where a Control Station cannot be used or is not needed.

In Single Site; IP Site Connect and Capacity Plus systems, the repeaters on which data will pass, require a NAI Data Licence. In Capacity Max systems, no NAI data licence is needed since this is part of the standard feature set.

MNIS can do the following:

• Layer 2 confirmed and unconfirmed data message delivery
• Individual and Group data messages
• Supports Basic; Enhanced (Alleged RC4), and AES256 Privacy
• Carries out message IP/UDP header compression
• Handles Data Precedence and Data Over Voice Interrupt access priority

MNIS supports MOTOTRBO Text Messaging; Location; Telemetry; External Data and OTAP. Ideally, MNIS is usually used with DDMS (a.k.a. Presence Notifier)  to process ARS messages.

If DDMS is deployed with MNIS, both radio presence (radio is there) as well as mobility notification (radio is where) are supported. The channel and site where a radio transmits its ARS message is recorded. MNIS subscribes with DDMS to receive mobility information, and uses this information to
route data to the radio wherever it is in the system.

MNIS acts as a destination for the above data coming from radios. It also acts as an IP tunnel for any data coming from the application and being directed to the radio. It therefore needs it own unique Radio ID.

MNIS however does not support repeaters which are set up in Analogue or Dynamic Mixed Mode. It also does not support layer 2 fragmented data. So you need to ensure that the largest data size [Data Message + IP/UDP Header] transmitted from the radio is less than the Max TX PDU Size configured in the radio codeplug.

There are some benefits of using a Control Station:

1. The PC and Control Station which is hosting the data application, does not have to be within RF range of any of the repeaters.
2. The PC hosting the application can be anywhere which has an IP connection to the repeater(s) that will pass data to/from the radios.
3. If more than one channel is needed, no additional Control Stations are needed. This also means, no costly combiner array (or no problematic antenna farm for all the control stations).
4. Redundant MNIS instances can be used and these can be on different hosts, in different locations.
5. No need for wide and local area channels.

Previously, IP Site Connect and Multisite Capacity Plus data revert channels had to be set up as wide area in order for the data messages to be routed to the site where the control stations are at. With MNIS, a centralized data application is able to access local Data Revert Channels at all remote sites. The wide area data revert channels can now be split into multiple local data revert channels, and each will route the data to the application, via the IP link and MNIS. This has the overall effect of increasing the total system data throughput capacity.

MNIS runs as a service, which means that it will start automatically when Windows starts. The user interface is a simple tool that allows you to configure a number of settings in very much the same way one would set up a radio.

It is possible to also have specific UDP ports forwarded to other IP addresses. This allows multiple host PCs to share a single MNIS instance.

If redundant MNIS applications will run on two separate host computers, MNIS status agent will be needed. This application senses whether MNIS is running and if not, will make the other MNIS service start.

In Capacity Max, MNIS is set up using Radio Management. The configuration is then exported as a GWCFGX file and imported into the MNIS configuration tool. The MNIS application would communicate with the various service running on the CMSS.

In order for it to work, MNIS must be running and there needs to be a static persistent route that directs any radio-bound data to the tunnel. There also needs to be an IP connections between the repeater(s) and application host PC. Also, remember to save and start your configuration (play button in the configuration tool).