6-4 The method for IPv6-IPv4 address translation by switching to the port translation automatically and recorded media

摘要

PURPOSE: An IPv6(Internet Protocol version 6)-IPv4 NAT-PT(Network Address Translation-Protocol Translation) method using an automatic port translation and a recording medium therefor are provided to prevent the waste of an idle time in which hosts of an IPv6 network wait until another address is released and enhance the utilization of an IPv4 address pool by automatically translating an address translation method into a port translation method when a use rate of an address pool to be translated is greater than a specific threshold value. CONSTITUTION: If IPv6 packets are transmitted from IPv6 hosts, an IPv6-IPv4 address translation device receives the IPv6 packets and compares a use rate of an IPv4 address pool with a predetermined threshold value for judging whether the use rate of the address pool is less than the predetermined threshold value(S11). If the use rate of the address pool is same to or greater than the predetermined threshold value, the IPv6-IPv4 address translation device automatically translates an address translation method into a port translation method for translating the IPv6 packets into IPv4 packets and transmitting the IPv4 packets(S15).