| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce the required storage area in the case of conversion between Internal protocol version IPv4 and IPv6 by storing only the total of check sums of one fragment packet and each fragment packet. SOLUTION: The IPv4-IPv6 converter is provided with a checksum re- calculation means 22 that calculates a check sum in a host layer protocol header of a fragment packet whose header is converted by a header conversion means 21, sums the result to a value having already been stored and stores the sum in a check sum storage section 32. When all fragment packets reach a transmission/storage control means 23, the control means 23 substitutes the check sum in the check sum storage section 32 to a host protocol check sum of fragment packets in a fragment packet storage section 33 and transmits the resulting fragment packets.</p> |
