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JN516x-EK001 Evaluation Kit
User Guide
JN-UG-3093 v1.5 © NXP Laboratories UK 2015 39
2.4 Network Formation and Topology
A wireless network is formed as follows:
1. The first node to be started is the Co-ordinator, which performs network
initialisation including the selection of the radio channel in which the network
will operate (see
Section 2.1 ) and the PAN ID of the network (see Section 2.3 ).
2. Once the initialisation is complete, the Co-ordinator allows other nodes to join
it as its ‘children’ - the Co-ordinator is referred to as a ‘parent’. These child
nodes can be Routers and/or End Devices.
3. Each Router may itself become a parent by allowing child nodes to join it
(which may themselves be Routers and/or End Devices). In this way, the
network grows.
A number of network shapes or topologies are possible, which are dependent on the
wireless network protocol used. These are the Star, Tree and Mesh topologies,
described in the sub-sections below.
2.4.1 Star Networks
A Star network contains only one routing node, which is the Co-ordinator. Thus, all
messages between the network nodes are routed via the central Co-ordinator.
Figure 28: Star Network
Co-ordinator