What is ZigBee Stack?
top ZigBee is based upon stack architecture that resembles standard OSI seven-layer model but defines only those layers relevant to achieving functionality in the intended scope. ZigBee Stack Architecture The ZigBee stack architecture is made up of a set of blocks called layers. Each layer performs a specific set of services for the layer above: a data entity provides a data transmission service and a management entity provides all other services. Each service entity exposes an interface to the upper layer through a service access point (SAP), and each SAP supports a number of service primitives to achieve the required functionality. IEEE 802.15.4 standard defines the lower two layers: the physical (PHY) layer and the medium access control (MAC) sub-layer. The ZigBee Alliance builds on this foundation by providing the network (NWK) layer and the framework for the application layer, which includes the application support (APS) sub-layer, the ZigBee device object (ZDO) and the manufactur
