Patent ID: 7068779

Claim:
A method for controlling echo canceling in a telecommunications network comprising a first switching center having no echo canceling equipment and at least one second switching center having echo canceling equipment, said method comprising establishing a call connection in a speech mode via said first switching center and said at least one second switching center so that the echo canceling equipment is connected to the connection, changing, under control of said first switching center, the type of call connection from the speech mode to another transmission mode in which echo canceling is not allowed, sending to said at least one second switching center from said first switching center a signaling message commanding said second switching center to disconnect the echo canceling equipment from the connection, changing, under control of said first switching center, the type of the call connection from said other transmission mode back to the speech mode, and sending to said at least one second switching center from said first switching center a signaling message commanding said second switching center to connect the echo canceling equipment to the connection.