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ZigBee protocol stack

ZigBee has a relatively simple protocol stack. It consists of three layers. The lowest layer is formed by IEEE 802.15.4 and consists of the Physical Layer (PHY) and the Medium Access Control (MAC). The layers above are defined by the ZigBee Alliance. They are the Network Layer (NWK), the Application Support Layer (APS), the Network Security Layer (SEC) and the Application Framework. The ZigBee profiles above these are application-specific profiles

. The physical layer implements the radio interface and media access, and also monitors transmission quality. The air interface uses spread-spectrum technology (DSSS) with a symbol rate of 62.5 S/s (symbols per second) and a data rate of 128 kbit/s. As a modulation technique, ZigBee uses two-phase shift keying (BPSK) in the UHF band and offset quadrature phase shift keying

(OQPSK) in the 2.4 GHz band.

ZigBee Protocol Stack

ZigBee Protocol Stack

The ZigBee header has several variable data fields and can have a size of up to 128 bytes

. The ZigBee address can be 8 bytes and is equivalent to IEEE addressing, short addressing is 2 bytes long.Above the lower layers defined by IEEE 802.15.4, are the ZigBee protocols defined by the ZigBee Alliance. This layer consists of the Network Layer (NWK) and the Application Support Layer (APS). In addition to the previous Network Layer, which could be used by all ZigBee profiles, another one was developed for ZigBee Smart Energy Profiles (ZSE), which works with the IPv6 protocol

. The Application Layer is located above the Network Layer and the Application Framework. It gets its access to the underlying layers via the ZigBee Device Object (ZDO). The applications generally have predefined ZigBee profiles.

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Englisch: ZigBee protocol stack
Updated at: 18.11.2015
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