Patent ID: 6173312
Filing Date: 2001-01-09
Classification: H04L

Abstract:
A network system, comprising:a first server computer;a second server computer;at least one client computer connected to a network;a network supervising means for supervising operations of the first server computer, and for instructing a server switching means that the second server computer is executed in place of the first server computer;the server switching means for setting an identification address, that is a network address of the first server computer, and a virtual address, that is a network address of the second server computer and corresponds to the identification address, in an address table of the second server computer in response to the server switching instruction;packet converting means for setting an identification address and a virtual address in an address mapping table of the a packet converting means in response to the server switching instruction, and for transmitting a packet after executing the conversion of the packet of which transmitting destination is changed to the virtual address, when the destination address of the packet received from the at least one of client computer corresponds to the identification address to be set in the address mapping table; andthe second server computer for setting a source address of an answering packet to the identification address, when the second server computer transmits the answering packet to the at least one client computer in request to the packet.