When opening a Telnet connection, there is negotiation on the network side to determine who generates the echo of the characters sent by the client. Either the client application generates a local echo, or the Telnet server generates a remote echo by immediately sending back all received characters. The Telnet echo option on the Com-Server is defined as follows: Telnet echo = active (2) The Com-Server negotiates a remote echo with the client application and local echo is deactivated. In this case the device serially connected to the Com-Server must generate the echo. Telnet echo = deactivated (1) The Com-Server tells the client application when the connection is opened that is not generating an echo, which results in activation of local echo. Local echo may have to be manually turned on on the Telnet client.