The ZIGBEE Cluster LIBRARY (ZCL) is a significant addition to REVISION 1.1. In ZigBee, a cluster is a message or collection of messages pertaining to a given application DOMAIN. Some devices (such as on/off switches) have the same definition and functionality whatever application profile is used. The idea behind creating the ZCL was to provide cluster reusability by abstracting clusters across several application domains and PLACING them in a library organized according to functional domains (e.g., lighting, closures, HVAC).

The ZigBee Cluster Library (ZCL) is a significant addition to revision 1.1. In ZigBee, a cluster is a message or collection of messages pertaining to a given application domain. Some devices (such as on/off switches) have the same definition and functionality whatever application profile is used. The idea behind creating the ZCL was to provide cluster reusability by abstracting clusters across several application domains and placing them in a library organized according to functional domains (e.g., lighting, closures, HVAC).