LVL1::IControlHistSvc Node1 LVL1::IControlHistSvc + DeclareInterfaceID() + SetHistSvc() Node3 LVL1::ControlHistSvc - m_histSvc + ControlHistSvc() + ~ControlHistSvc() + initialize() + SetHistSvc() Node1->Node3 Node2 extend_interfaces1 < IAlgTool > Node2->Node1