Patent ID: 7444578

Claim:
A method of controlling a data unit sender, having a send buffer for storing data units to be sent, arranged to operate in accordance with a communication protocol that provides for a feedback function, wherein a sender in a data unit communication receives feedback messages from a receiver that reports on the receipt of data units, said method comprising: controlling the flow of data sent by said data unit sender, such that at any given moment the amount of previously unsent data that the sender can send at once is limited by an available transmission capacity value, detecting a time-out monitoring procedure triggering event, utilizing a time-out monitoring procedure for monitoring whether a feedback message for a designated data unit arrives before a predetermined time-out period (S-RTO) has expired, said predetermined time-out period (S-RTO) starting at the occurrence of the time-out monitoring procedure triggering event, and for retransmitting the designated data unit if said predetermined time-out period (S-RTO) expires without said acknowledgment message having arrived, wherein said predetermined time-out period (S-RTO) is a first time-out period, and utilizing said time-out monitoring procedure to perform a retransmission of said designated data unit upon expiration of a second time-out period (Q-RTO) shorter than said first time-out period, if upon the expiration of said second time-out period (Q-RTO) said available transmission capacity value for unsent data is greater or equal to the size of said designated data unit.