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SNAPlink User Guide — 116-081614-031-A000
No Mesh
In contrast, the
No Mesh
configuration tells a device to not aid other devices when they are trying to establish routes.
With the No Mesh configuration, each node is still perfectly happy to make use of other willing participants in the
mesh network, but will not volunteer to forward messages for other nodes.
The advantage of this configuration, even in an isolated environment without outside nodes asking for assistance, is
your devices will perform their route discovery tasks once and then not allow those found routes to time out,
reducing a small amount of overhead every minute or so. This means if your devices spend a significant amount of
time idle and then need to send a burst of data, that burst will not be subjected to increased latency by the need for
route discovery.
Mesh Routing Maximum Timeout
The
Mesh Routing Maximum Timeout
setting specifies how long a discovered route can survive before it is
discarded and route discovery has to happen again. The Mesh configuration sets this to 60,000 milliseconds, or one
minute. (The maximum value is 65,535 milliseconds.) Setting the value to zero instructs that routes should never
time out, and will only be discarded if they are found to be unusable. The
No Mesh
configuration sets this to zero.
Mesh Override
The
Mesh Override
setting specifies whether a device is willing to pass along directly addressed messages for
other devices. Devices that are directly paired and slave nodes in a point-to-multipoint arrangement send their
messages as addressed messages, so these could be affected by this setting. If you have multiple paired point-to-
point devices, these devices could also be configured to route and relay messages for each other.
Turning Mesh Override off does not mean that the device is unable to take advantage of the mesh network for its
own purposes. It only means that it will not be a polite citizen in its mesh environment, forwarding directly addressed
messages for other nodes.
Disabling this setting on an intermediate SNAPlink device in an environment where one or more devices have
difficulty communicating reliably with another device can allow that intermediate device to relay the other slaves'
messages to the master.
In an environment where every SNAPlink device can directly communicate with every other device this setting is
irrelevant.
Multi-cast Forwarded Groups
The
Multi-cast Forwarded Groups
setting performs a similar function as the
Mesh Override
setting, only for
multicast messages rather than for directly addressed messages. In the context of SNAPlink devices, the only
multicast messages typically sent are from the master to the slave(s) in a point-to-multipoint configuration.
Enabling this setting on an intermediate SNAPlink device in an environment where the master has difficulty
communicating with one or more slaves can allow that device to relay the master's messages to the more slaves.
In an environment where every node can directly communicate with every other node, this setting is unnecessary,
and enabling it can add overhead to any device on which it is enabled.