Function Blocks method which meets the standard IEC 61499 is applied to the implementation of specific details of the digital substation interlocking CILO in the IEC 61850, making the static structures of CILO executable. Digital substation mapping architecture is established which making the designed function block can be compatible with both IEC 61850 and IEC 61499. The CILO interlocking communication module is given in the paper. Moreover, safety expansion for the communication GOOSE message and security GOOSE message is designed based on IEC 62351-6, which not only meets the demands of real-time communication, but also have a high safety degree. The communication of interlocking and security authentication process is described.