| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent buffer overflow at a LAN side receiving buffer and a WAN side transmitting buffer of a relay device, and further prevent forceful disconnection of connection even in the case the line bandwidth of the WAN side is smaller than the line bandwidth of the LAN side in the relay device for relaying two sessions of TCP communication at the LAN side and WAN side. <P>SOLUTION: A communication device controls the value of a receiving window size (rwnd) described in an ACK packet to be returned to a transmission terminal at a LAN side, based on the total value of a transmission through-put, a discard rate, and an RTT measured about TCP communication at a WAN side, a non-aligned data size and an aligned data size of a receiving buffer of the LAN side, and a data size soon to be transmitted and an ACK-waiting data size of a transmitting buffer at the WAN side. Furthermore, when the rwnd decreases and falls under a predefined threshold value, and then exceeds the threshold value again, an ACK packet describing the value of the receiving window size (rwnd) is immediately transmitted to a transmission terminal at the LAN side. <P>COPYRIGHT: (C)2013,JPO&INPIT |
