Method and system for an optimized retransmission of a message in a satellite communications context

A communications method for the retransmission of at least one fragment of lost or erroneous message from a terminal to a gateway on a communications network comprising a plurality of terminals, communicating by means of a communications resource over a demand assignment multiple access, said communications network further comprising a control centre allocating the communications resource to the terminals, said method comprising:

• transmission of a first allocation plan for the communications resources from the control centre to the terminal and to the gateway,
• transmission of the message from the terminal to the gateway according to the first allocation plan,
• detection, by the gateway, of fragments of lost or erroneous messages and, when at least one fragment of lost or erroneous message is detected, the notification via the gateway to the control centre of the loss of at least one fragment of the message,
• calculation, by the control centre, of a second allocation plan taking into account a new transmission of the fragment of lost or erroneous message,
• notification via the gateway to the terminal of the loss of the fragment of message and the notification by the control centre to the terminal of the second allocation plan taking into account a new transmission of the lost fragment of message, and
• transmission by the terminal of the lost fragment of message according to the second allocation plan to the gateway.