The boss-secretary module creates a special ring group which includes one or more "bosses" and one or more secretaries". When someone calls the boss' extension, the secretary (or secretaries) extension will ring only, allowing the secretary to answer his or her boss' call.
Additionally, you can define one or more chief extensions, who may call boss extension directly without ringing the secretary's extension.
The module includes codes for activating, deactivating and toggling the groups' state. For example, when a secretary ends her working day, she may turn off the boss-secretary group dialing *152, so her boss will receive calls directly.
The module generates the appropriate hints to have ip phones show the groups state by subscribing to the *152 extension. You can set this functionality to blf button on your phone.
For example for Linksys/ Cisco phones:
fnc=blf+sd;sub=*152EXT@$PROXY;ext=*152@PROXY