| 摘要 |
A method and apparatus for detecting whether a remote party has added a secondary telephone destination to a telephone call, for example through the activation of three-way calling service, conference calling or two lining bridging, by identifying an echo characteristic to the telephone connection between the local and the remote telephone and monitoring the echo characteristic to determine whether there is a significant change. The addition of a secondary telephone destination can be verified by continuing to monitor the echo characteristic to determine whether it has returned to its original value. |
