Tongda OA interconnection components are used for mutual communication and exchange between head office and branch offices. The head office completes the communication link operation with the branch by configuring the system interface settings and the interface settings in the interconnection module. The branch completes the communication link operation with the headquarters by configuring the address configuration in the access OA headquarters module. Before communicating with each other, the headquarters company and branches need to submit a visit application, and the other company can only visit after approving the visit application.