Patent ID: 7561581

Claim:
A method of allocating an Internet Protocol (IP) address and detecting duplicated of the IP address in a network environment, comprising the stops of: allocating an initial IP address to a terminal, by the terminal; sending and receiving broadcast messages; detecting duplication of the IP address while sending and receiving the broadcast messages; updating a Duplicate Address Detection (DAD) table through searches of a DAD table and a history table; and determining whether a collision of the IP address occurs using a DAD timer handler, wherein the broadcast messages are one-hop broadcast messages, and each entry of the Duplicate Address Detection (DAD) table is periodically updated by the one-hop broadcast messages, wherein each entry of the DAD table includes an IP address of at least one of a plurality of terminals in a network, a sequence number of the at least one of the plurality of terminals, a temporary ID of the at least one of the plurality of terminals and a flag, and wherein the history table stores a latest sequence number and temporary ID generated by a present terminal.