The BARP (Barix Paging) protocol was invented by Barix to address multiple devices in a network with single broadcasts or multicasts only. This is reducing the network load and the addressed BARP clients execute the commands at the same time.
Only some ABCL firmwares are using the BARP protocol, e.g. IClient/IMaster, the ICPaging, the IPaging for Zones and the BARP Paging.
But also the new Exstreamer M400, Exstreamer MPA400, IPformer and Annuncicom MPI400 are supporting the BARP paging protocol (as client).