Patent ID: 7035941
Filing Date: 2006-04-25
Classification: H04L

Abstract:
1. A method of selecting an IP address for an added device that does not overlap with other addresses among an effective address range permitted as IP addresses, the method comprises the steps of: detecting and collecting addresses of all other devices connected with the added device to a network by receiving and analyzing signals flowing through the network; sectioning binary numerals of the collected IP address at Nth bit (1≦N≦K, K is a predetermined natural number) from a minimum digit, and defining digits not less than the Nth bit as high rank bits and digits lower than Nth bit as low rank bits; judging whether all of the high rank bits of the collected IP addresses are the same; if all of the high rank bits are not the same, changing N to N+1, N−1, or to a desired number, and sectioning the binary numerals in the step of sectioning to make the judgment at the judgment step; repeating the number changing step until all of the high rank bits become the same; if all of the high rank bits are the same, adopting a value expressed by a binary number composed of the same high rank bits and low rank bits set all to 0 as an IP network address, and adopting a value expressed by a binary number composed of high rank bits set all to 1 and low rank bits set all to 0 as subnet mask; and selecting an IP address, which is different from the IP address of any other device connected to the network, from among a group of effective IP addresses defined by the IP network address and the subnet mask.