3.1.1.1.2 State Machine Call Abort

The following figure shows the state machine when a call is aborted.

Common details for call abort

Figure 3: Common details for call abort

To abort an SSTP connection, the SSTP client and server state machines have the following states:

State Name

Description

Call_Abort_In_Progress_1

This is the initial state when the SSTP connection reaches abort-related conditions, such as the receipt of an invalid message, as described in the client and server state machines in sections 3.2.1 and 3.3.1. In this state, SSTP_MSG_CALL_ABORT is sent to the SSTP far end, and CurrentState is changed to Call_Abort_Pending.

Call_Abort_In_Progress_2

This is the initial state that the SSTP connection transitions to when the SSTP_MSG_CALL_ABORT message is received from the SSTP far end. In this state, SSTP_MSG_CALL_ABORT is sent to the SSTP far end, and CurrentState is changed to Call_Abort_Timeout_Pending.

Call_Abort_Pending

In this state, the SSTP connection waits for the SSTP_MSG_CALL_ABORT message from the SSTP far end. When an SSTP_MSG_CALL_ABORT (section 2.2.13) message is received, or when a lower layer disconnects or times out, the Call Abort is completed. Other than SSTP_MSG_CALL_ABORT, any SSTP control message received while in this state is silently discarded.

Call_Abort_Timeout_Pending

In this state, the SSTP connection waits for the timer to expire or for the lower layer to be disconnected. When either of these conditions is met, the Call Abort is completed. Any SSTP control message received while in this state is silently discarded.