US 9,813,503 B2
IP-address distribution system utilizing a plurality of switching devices grouped into two or more groups
Tetsuya Shigeeda, Tokyo (JP); and Shingo Honda, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Chiyoda-Ku, Tokyo (JP)
Appl. No. 14/111,296
Filed by Tetsuya Shigeeda, Tokyo (JP); and Shingo Honda, Tokyo (JP)
PCT Filed Jun. 30, 2011, PCT No. PCT/JP2011/065059
§ 371(c)(1), (2), (4) Date Oct. 11, 2013,
PCT Pub. No. WO2013/001641, PCT Pub. Date Jan. 3, 2013.
Prior Publication US 2014/0032734 A1, Jan. 30, 2014
Int. Cl. G06F 15/173 (2006.01); H04L 29/08 (2006.01); H04L 29/12 (2006.01); H04L 12/931 (2013.01); B61L 15/00 (2006.01)
CPC H04L 67/12 (2013.01) [B61L 15/0036 (2013.01); B61L 15/0072 (2013.01); H04L 49/355 (2013.01); H04L 61/2015 (2013.01); H04L 61/2038 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An IP-address distribution system comprising:
a network formed by a plurality of switching devices; and
a plurality of IP-address distribution devices connected to the network, wherein the switching devices are grouped into two or more groups, wherein at least one of the IP-address distribution devices is connected to a sub-network, which is a network formed by switching devices in a same group, and
a switching device, among the switching devices, having a physical port connected to another switching device in another group is configured to interrupt, at the physical port, an IP-address request signal, transmitted to the plurality of IP-address distribution devices from a terminal included in a first group that requests allocation of an IP address from the plurality of IP-address distribution devices, wherein the interruption includes blocking passage of the IP-address request signal between a logical port of a first switching device in the first group and a logical port of a second switching device in a second group and preventing the IP-address request signal from reaching at least one of the plurality of IP-address distribution devices which is connected to a sub-network of the second group that is different from the first group.