9.2.2 Asynchronous Event Codes

In most cases any output from the DCE will be in response to the receipt of a command from the DTE. There are cases, however, where an asynchronous event occurs that the DTE will need informing of (for example. disconnection from the network). The DCE uses Asynchronous Event Codes (AEC) to convey such events; AECs use the same format conventions as regular responses with an initial <CR> to clearly identify the start of the AEC:

<CR>+AECNAME:INFO<CR><LF>

To avoid confusion at the DTE, AECs will not be sent during the execution of a command. However the DTE must be prepared to receive AECs at any time as it is possible for the DCE to send ACEs resulting from a previous command or condition while the DTE is transmitting a new command.