You use dial mode (that is used by Systems Network Architecture (SNA) controller descriptions) to send a connection request to a remote device.
Dial mode starts when you vary on the controller description. During the dialing process, the system polls the remote device to determine if the device is ready to transmit. If the remote device is ready, the connection process continues. Successful connection is still possible even if the local and remote devices dial each other simultaneously.
These controller description fields control the frequency and duration of the polling:
If the remote device answers the poll within the time that these parameters specify, your system proceeds with establishing the connection. If not, your system sends an inquiry message (CPA58E0 or CPA57EF) to the system operator message queue. This message indicates that a connection attempt failed and that the controller description is now in answer mode.