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Rev. 0.1

3.2.1. Initialization

Each device must be reset via the NLME-RESET primitive immediately on powerup.

3.2.2. Starting a ZigBee Coordinator

A network is established by designating a node as the ZigBee Coordinator. The Application layer must first instruct

the Coordinator to form a network then must permit other ZigBee devices to join the network. This is illustrated in

Figure 2.

For a more robust design, the Coordinator's nlmeNetworkFormationRequest()will usually include an active

scan to detect its neighboring environment. One possible SCAN outcome will be PAN ID conflict. This is a very

important exception that programmers should be aware of so any problem can be handled and detected before the

Coordinator starts.

"Permit Join" can be used creatively. Many examples have been discussed suggesting that "Permit Join" is toggled

on and off by a simple push button. This is one idea how the Coordinator can fend off unsolicited JOIN requests

and protect the integrity of the subject network.

Figure 2. Establishing a Network and Enabling Nodes to Join

ZigBee Coordinator

Application Layer

Network Layer

nlmeResetRequest(...)

nlmeNetworkFormationRequest(...)

confirmation by return value of

nlmeResetRequest(...)

confirmation by return value of

nlmeNetworkFormationRequest(...)

nlmePermitJoiningRequest(...)

confirmation by return value of

nlmePermitJoiningRequest(...)