Router; End Device - Digi XBee Zigbee Mesh Kit User Manual

Zigbee Mesh Network Setup
PAN ID (ID). Determines the PAN ID. If set to 0 (default), the device selects a random PAN ID.
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Scan Channels (SC). Determines the scan channels bitmask the coordinator uses to form a
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network. The coordinator performs an energy scan on all enabled SC channels.
Scan Duration (SD). Sets the scan duration, which determines how long the coordinator
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performs an energy or active scan on a given channel.
After the coordinator has started the network, it can allow new devices to join it (up to 20 devices).
The permit joining attribute is configurable with the Node Join Time (NJ) command. The coordinator
can also route data packets and communicate with other devices on the network.
Note You can configure it to always allow joining (FF) for up to 254 seconds. However, Digi discourages
this due to the security risk.

Router

Routers must discover and join a valid Zigbee network before they can participate in it. To discover
nearby networks, the router performs an active scan, just like the coordinator does when it starts the
network. When a router joins a network, it receives a randomly selected 16-bit address from the
device that allowed the join .
Once a router joins a Zigbee network, it remains connected to the network on the same channel and
PAN ID as long as it is not forced to leave. If the scan channels, PAN ID, and security settings do not
change after a power cycle, it remains connected to the network after a power cycle. There are two
provisions to automatically detect the presence of a network and leave if the check fails:
Join Verification (JV). If enabled, the XBee attempts to discover the address of the coordinator
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when it first joins a network.
Network Watchdog Timeout (NW). Used for a powered router to periodically check for the
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presence of a coordinator to verify network connectivity.
After a router has joined a network, it can allow new devices to join the network (up to 20 devices
each router) with the Node Join Time (NJ) setting. It can also route data packets and communicate
with other devices on the network.

End device

Similar to routers, end devices must also discover and join a valid Zigbee network before they can
participate in it. End devices also discover networks by issuing an active scan, and when they join a
network they receive a randomly selected 16-bit address from the device that allowed the join.
Since an end device may enter low power sleep modes and not be immediately responsive, it relies on
the device that allowed the join to receive and buffer incoming messages on its behalf until it is able to
wake and receive those messages. The device that allowed an end device to join becomes the parent,
and the end device becomes the child. The end device polls its parent when it is awake to query for
any new received data packets.
Coordinators and routers maintain a table of all child devices that have joined. This table has a finite
size and determines how many end devices can join. You can use the Number of Remaining Children
(NC) setting to determine how many additional end devices can join a coordinator or router.
After an end device has joined a network, it can communicate with other devices on that network.
Since end devices are intended to be battery powered and therefore support low power (sleep)
modes, they cannot allow other devices to join, nor can they route data packets.
XBee® Zigbee® Mesh Kit
Startup operations
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