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Figure 8.19 ZigBee and the ISO network layers.

Data sent through the ZigBee network is in packets similar to the Ethernet format. Figure
8.20 shows how these packets are initially constituted at Layer 2, or MAC as it is referred to
in the figure. These packets may be subsequently modified at higher layers, as needed,
to suit the real-time network communication needs.
There are four packet types that exist in ZigBee:

1. Beacon
2. Data
3. MAC Command
4. ACK

Figure 8.20 ZigBee packet formation.