In the unlikely event that the Travelfusion system takes too long to respond to a StartBooking request and the client system therefore has to 'timeout' the request, this should not be treated as a failed booking. The booking may in fact have been successfully initiated and may subsequently complete successfully. In such cases, the customer is advised to treat the booking as Unconfirmed (uncertain status) and inform the end user accordingly and apply the appropriate operational procedures.
Unrecognised or unexpected responses from the Travelfusion server should also be treated similarly, including schema validation failures. In fact, the customer system should assume that a booking may have been made regardless of the contents of the StartBooking response (or lack thereof).