MOTOTRBO IP Networking Requirements

MOTOTRBO utilises a proxy discovery mechanism to learn about the network. All Peers (Repeaters, RDAC, 3rd Party Applications) initially communicate with the Master and then learn of the rest of the system. When a Peer joins the Master, the Master will inform the newly joined Peer about any other peers on the network, and then informs the other Peers about this newly joined Peer. This mechanism allows all of the Peers in the network to communicate directly with one another.

This information consists of the IP address and port used by all Peers in the system and is retrieved by Master from the messaging the Peer sends when requesting to join the system. Therefore the addressing that the Master sees with respect to a peer must be the same addressing that any device in the system can use to contact that peer.

The above discovery mechanism allows for easy system installation but puts specific requirements on the IP topology based on the system type. Below is a list of MOTOTRBO systems and their IP topology requirements based on the network location of the Master with respect to the network location of any peer.

NB! As of release 2.2, NAT Loopback is no longer a requirements for the Routers used in Linked Capacity Plus.

The Hair-Pinning/NAT-Loopback feature allows for a message from a LAN IP address, destined for the WAN IP address of a router, to be transmitted back into the LAN after going through the Firewall and NAT rules of the router. Therefore a local message will appear to have come from the WAN.

System Type
Which is the Master?
Which are the Peers?
System Topology
Type of IP Routing Required
IPSC
One repeater
Other Repeaters, RDAC, Third Party Applications
All Repeaters in the same subnet behind the same router
Basic LAN



Master and another Peer behind a single subnet with other Peers in a different subnet
Hair-Pinning/NAT-Loopback required in the router that creates the subnet where the Master resides. Full Cone NAT support required across IP topology.VPN Tunnel can be used to flatten out the topology
Capacity Plus
One repeater
Other Repeaters, RDAC, Third Party Applications
All Repeaters in the same subnet behind
the same router
Basic LAN



Master and another Peer behind a single subnet with other Peers in a different subnet
Hair-Pinning/NAT-Loopback required in the router that creates the subnet where the Master resides. Full Cone NAT support required across IP topology.
Linked Capacity Plus
One repeater
(The master supports
two IP interfaces and
acts both as a Master
and as a "virtual" peer)
Other Repeaters, RDAC, Third Party Applications
Master and its site peers behind a single subnet while other sites reside behind another subnet.
Hair-Pinning/NAT-Loopback required in the router that creates the subnet where the Master resides. Full Cone NAT support required across IP topology.
Note: To qualify a router for LCP – follow Router compatibility test procedure for LCP system.





Underlying Requirement
The IP/Port addressing that the Master sees with respect to a peer MUST be the same addressing that ANY entity in the system can use to contact the peer if it is required to do so.


6 comments:

  1. This comment has been removed by a blog administrator.

    ReplyDelete
    Replies
    1. This comment has been removed by the author.

      Delete
  2. Hi Wayne!
    My name is Luiz, from Brazil. I am SmartPTT distributor and I had been working on MOTOTRBO systems for the last 3 years.
    Now I faced a situation were the customer, due to low band width, does not need data from local slots of several master repeaters in IPSC to be transmitted on the network.
    I know that even when master repeater has a local channel, when a SU transmits on that channel, software can have voice and data information...
    Do you have any idea, or faced something similar, that can help me to "filter" voice traffic from master local slot and consequently not overload the IP network?

    ReplyDelete
    Replies
    1. Hi Luiz,

      I assume you have tried changing the IP Site Connect setting (drop-down) in the repeater channel? This way only voice from one of either slots is passed onto the IP cloud.

      There are other ways of reducing the amount of traffic on an IP Site Connect (and to a lesser extent, Linked Capacity Plus) network, which, the local Motorola support team would be able to assist you with.

      Delete
  3. Hi Wayne!

    I have read in the System Planner and also have been strongly advised by the provider not to transmit anything else in the backhaul network other than the MOTOTRBO information. Is there a specific reason not to do this?
    We would like to be able to send other information to the site, like telemetry signals, maybe one or two IP cameras or install a VoIP phone to provide secondary communication on site as per R56 recommendations.
    What are the risks of doing this? Could we only improve the backhaul network and then remove this risk?

    Thank you!

    ReplyDelete
    Replies
    1. The answer depends on what flavour of MOTOTRBO you are using: For IP Site Connect, there shouldn't be any problems as long as the IP network can support the required bandwidth.

      Linked Capacity Plus generally requires that each site is on its own Router - nothing else, other than the repeaters, should be connected to that Router. IP Cameras, Phones etc. can be connected on to another Router or directly to the WAN.

      The same goes for Connect Plus.

      The problem comes in when the repeaters and other devices share the same physical network: Linked Capacity Plus uses local broadcast for channel management on site and this could interfere with the operation of other devices (or those devices could interfere with the repeaters).
      In some (rare) cases, the repeaters in a IP Site Connect / Linked Capacity Plus network could go offline if subjected to an IP flood - the way to avoid this is to put the repeaters on their own Router (and disable ping responses in the Router :-)).

      Delete

Powered by Blogger.