Components of Opengate System

Client MachineUser terminal.
Gateway MachineControl of network usage. A CGI program (main component of Opengate) opengatesrv.cgi authenticates user and control the firewall ipfw. Web server to controll CGI program are also set.
Authentication ServerHold user information and reply to the authentication request.
Log ServerReceive date, time, userid, and ip-address for usage via syslog.

Requirement of Client Machine

NecessityWeb browser can run on the client. Ajax or JavaVM is desired.
Condition to open network Reply correct userID and password to the authentication page
Condition to close network When (Ajax or JavaVM) is enabled and the usage duration is not entered.
- Close Web browser or OS
- Fail periodic live check
Other cases
- A fixed time length passes.
- No packet passed from/to the client for a long time
- ARP command returns the different MAC address
- The user clicks the termination link in accept response page.
Applied networkTCP/IP communication, Wire/wireless LAN.
No address translation between gateway and client.
Applied machinesMobile PC/desktop PC, Service terminal settled by the organization/Note PC carried in by users.

Requirement of Gateway Machine

OSFreeBSD newer than 4.0
hardwarePC which can runs FreeBSD, Two EtherBoard
required softwareApache, ipfw
recommended softwarenatd, DHCP, SSL, perl, BIND

Requirement of Authentication Server

ProtocolsPOP3, POP3S, FTP, FTPS, RADIUS, or PAM
ConfigurationThe serverID and its configuration are set in opengatesrv.conf.
Choosing ServersIn case of entering [user] only, authentication request is sent to the default server. In case of entering [user@serv], request is sent to the server set for extraID [serv].

Merits of Opengate

Wide compatibilityIt only requires web browser for the client. It can be compatible with clients having various OS and connecttion form.
Easy managementIt can use existing autheitication servers. Only the gateway system should be maintained. No installation and user guidance are required.
Easy interfaceIt has the friendly interface for web users. The network is opened by replying userid and password to the automatic-send authentication page. The netowrk is closed at the termination of the web browser.
Quick responseIt opens and closes the network with very short time delay after user action.
Wide applicabilityIt does not depend specific software and hardware. It can be inserted to the existing network easily. It can control both of IPv4 and IPv6.
High flexibilityThe network control depends on ipfw rules. Simple perl script is used to add rules.
Low costIt can be used under GPL. It uses no specific hardware or software. The gateway machine is a simple PC in which FreeBSD works.