A switching apparatus for constructing a system integrating a telephone switching network and a LAN includes: line interface sections, each connected to a transmission line for transmitting a signal on which low-speed data and high-speed data are multiplexed; a low-speed data switch for switching low-speed data demultiplexed in each line interface section; a high-speed data switch for switching high-speed data demultiplexed in each line interface section; and a processor for monitoring and controlling the data traffic passing through the low-speed data switch and high-speed data switch. An address in a designated position in the high-speed data demultiplexed in each line interface section is read out, whereby the association between the low-speed data terminal and high-speed data terminal is identified and stored. By referring to this association, management of LAN terminals can be performed using the maintenance operation procedures used in a conventional electronic switching apparatus.