User's Manual

9
The Network Manager uses health reports to continually optimize the network to maintain >99.999%
data reliability even in the most challenging RF environments. The use of TSCH allows SmartMesh
devices to sleep in between scheduled communications and draw very little power in this state. Motes
are only active in time slots where they are scheduled to transmit or receive, typically resulting in a duty
cycle of < 1%. The optimization software in the Network Manager coordinates this schedule
automatically. When combined with the WSM2400 low power radio, every mote in a SmartMesh
network—even busy routing ones—can run on batteries for years. By default, all motes in a network are
capable of routing traffic from other motes, which simplifies installation by avoiding the complexity of
having distinct routers vs non-routing end nodes. Motes may be configured as non-routing to further
reduce that particular mote’s power consumption and to support a wide variety of network topologies.
Figure 2. Mesh network
At the heart of SmartMesh motes and network managers is the WSM2400 IEEE 802.15.4e System-on-
Chip (SoC), featuring Dust Networks’ highly integrated, low power radio design, plus an ARM Cortex-M3
32-bit microprocessor running SmartMesh networking software. The SmartMesh networking software
comes fully compiled yet is configurable via a rich set of Application Programming Interfaces (APIs)
which allows a host application to interact with the network, e.g. to transfer information to a device, to
configure data publishing rates on one or more motes, or to monitor network state or performance
metrics. Data publishing can be uniform or different for each device, with motes being able to publish
infrequently or faster than once per second as needed.