User's Guide

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Depending on the transmission method used, payload data can be send to any device
in the network.
3.3.4.1 Speed Routing
Both Acknowledged and Non-Acknowledged transmissions types are using Speed
Routing to route the payload data from source to destination. Speed Routing is a
patented technology used exclusively in NeoMesh.
The Speed Routing algorithm identifies the fastest path from source to the destination,
taking into account paths with radio noise which would potentially slow down the
delivery of the payload data.
Because the routes are being generated all the time as a background task, changes in
topology (ie. nodes moving around – either nodes on-route or even the destination
node) do not impact the delivery of the payload data. Because the routes are being
maintained all the time, there is no such thing as a “bad route” which needs to be
healed like seen in other Mesh Network implementations.
Speed Routing is based on a “next-best-hop” principle, where each node has a routing
table containing information on which one of its current neighbours is the best
candidate to route a message to a given sink node (destination).
Speed Routing can handle up to 128 sink nodes. This means that in a given network, up
to 128 nodes can be configured to be destinations for routed payload data. All nodes in
the network acts as routers.
3.3.4.2 Acknowledged Transmissions
This is the most reliable type of payload data transmission. It corresponds to TCP
transport known from IP networks, where the originating node will receive an
acknowledge message once the payload has been delivered at the destination.
When the application wants to send payload data to a sink node, all it has to do is
specify the Node ID of the intended sink node along with the actual payload data. The
protocol will then automatically route the data to the destination. Once the data has
been delivered, an acknowledge packet will be routed back to the source and will be
delivered at the application layer.
If no acknowledgement has been received within the configured timeout window, the
protocol will automatically retry the packet a configurable number of times, say three
times for this discussion (see Configuration Parameters). If the acknowledge is not
received during the retries, a non-acknowledge (Nack) message will be delivered to the
Application layer. This could happen for example, if the destination node was removed
from the network, and so, this mechanism allows the application to take action,
according to the needs of the application.