VLAN

LANNetwork design and operation for Niigata University

wireless LAN system using dynamic VLAN assignments

† † †Kazuyuki YAMAMOTO†, Shigeyoshi AOYAMA†, Kenji MIKAWA†

yamamoto@cais.niigata-u.ac.jp

†Center for Academic Information Service, Niigata University

18 LAN

DHCP IP HTTP

24 IP

IP

IP

IP

VLAN IP

LAN

AbstractThe wireless network system on Niigata University campus installed in 2007 has worked well. Below is an

overview of how university members use this system; wireless network computers are assigned global IP addresses bya DHCP server and any HTTP communications are redirected to a web authentication page in order to authenticatethe members. The system contributed to reducing the management burden of network operations because of easytracking of users and their computers. The number of smartphone and tablet users increased very rapidly at recentNiigata University, and since about 2012, we recognized a serious problem that the system run out of global IPaddresses for being assigned to wireless network computers. Since in our wireless network design, always-on wirelessnetwork devices were assigned global IP addresses before authentication, they might have occupied the addresseswithout authentication. It followed that the other members who really wanted to use wireless network could notaccess the network. In order to solve the shortage of global IP addresses with maintenance of easy tracking of users,we improved the existing system to assign wireless network computers which have passed user authentication withglobal IP addresses using dynamic VLAN assignments. In this paper, we detail an overview of the improved wirelessnetwork system and finally, evaluate the benefits of our system from the result of network operations.

LAN IP VLANKeywords

Network design, Wireless LAN system, Saving IP address, Dynamic VLAN assignment

学術情報処理研究 No.18 2014 pp.43−52

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14 7 LAN

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Mon Tue Wed Thu Fri

05/19-05/23 global05/19-05/23 private05/26-05/30 global

05/26-05/30 private06/02-06/06 global

06/02-06/06 private06/09-06/13 global

06/09-06/13 private06/16-06/20 global

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