The operation table of the called test of the PSTN call emulation test. It is used to realize the called test of the PSTN call emulation test, which is used to test whether a user of a port functioned as the called party can make a call. The index of this table is ifIndex. Operation table for the PSTN telephone test: It realizes the function of the test on subscriber phones in the system. This test helps test the features of the subscriber phone and check whether a subscriber phone works in the normal state.