Reference Manual

3. Configuring Point-to-MultiPoint Networks
FGR3
User-Reference Manual
LUM0110AA Rev Jan-2019 Page 72 of 143 Copyright © 2019FreeWave
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3.6. Routing Communications through the Network
When using the Network ID, a Repeater or Slave links to the first Repeater or Master it hears
with the same ID.
l Use Subnet IDs to determine the path a Repeater or Slave uses to communicate back to
the Master.
l Subnet IDs are particularly helpful to force:
l Two Repeaters in the same network to operate in series rather than in parallel.
l Slave radios to communicate to a specific Repeater for load balancing purposes.
Note: Forcing the communications path optimizes the performance of the network by ensuring the
Repeater or Slave links to a Repeater or Master with robust RF communications. Subnet IDs can
help to minimize latency.
3.6.1. Assigning Subnet ID Values
Subnet IDs consist of two parts, both available on the MultiPoint Parameters tab:
l Rx - This setting identifies which radio a Repeater or Slave listens to.
l In the terminal interface, this is the Rcv Subnet ID.
l Tx - This setting identifies the ID this device transmits on and which devices listen to it.
l The Tx Subnet ID parameter is relevant for MultiPoint Master radios and Repeaters
only.
l In the terminal interface, this is the Xmt Subnet ID.
l The default (disable) setting for both Rx and Tx is F, F.
l This is a visual way to indicate that the device is the final in the line of communication and
does not use a subnet ID.
l A MultiPoint Slave with a Subnet ID of F, F does not roam from one Repeater or network
to the next.
l It only links to a Master or Repeater that has either a Transmit Subnet setting of 0 or an
F, F Subnet ID.
l Setting both Rx and Tx Subnet ID to 0 allows a mobile Slave to roam from subnet to
subnet, and possibly from network to network, provided the Network ID, Max and Min
Packet Size, and RF Data Rates are the same between networks.
The examples in this section show the subnet definitions from the Master radio through the
network to the Slave radios. When the subnet path is defined, the Slave radios can follow the
route back to the Master.