Patent ID: 7233572

Claim:
A method for transmitting a packet in a packet transmission apparatus connected to a transmitter through a wired link and connected to a receiver through a wireless link, comprising the steps of: a) setting up an indirect acknowledgement timer to a data packet received from the transmitter, storing the data packet into a buffer and transmitting the data packet to the receiver; b) updating a size of the buffer based on an acknowledgement packet received from the receiver and treating the data packet received from the transmitter; and c) transmitting an indirect acknowledgement packet to the transmitter according to a state of the buffer in case an acknowledgement packet is not received from the receiver until the indirect acknowledgement timer is elapsed, wherein step b) includes the steps of: b1) if the acknowledgment packet is a new acknowledgement packet, changing a size of the buffer by calculating a round trip time (RTT) of the wireless link; b2) deleting the data packet corresponding to the acknowledgement packet received from the buffer; b3) setting up the indirect acknowledgement timer to a data packet stored in the buffer, which is the next data packet of the deleted data packet; and b4) determining whether the indirect acknowledgement packet of the data packet corresponding to said received acknowledgement packet is transmitted, and if the indirect acknowledgement packet is not transmitted, transmitting the received acknowledgement packet to the transmitter.