3The guest enters the provided access information.
4Once authentication is successful, CAS informs VSG to allow Internet access to the guest.
6.1.3Accounting Methods
The VSG provides two accounting methods: Accumulation and Time to Finish.
•The Accumulation accounting method allows multiple re-logins until the allocated time period or until the subscriber account is expired. The VSG accounts for the time the subscriber logs in for Internet access.
•The Time to Finish accounting method is good for one-time logins. Once a subscriber logs in, the VSG stores the MAC address of the subscriber’s computer for the duration of the time allocated. Thus the subscriber does not have to enter the user name and password again for re-login within the allocated time. Once activated, the subscriber account is valid until the allocated time is reached even if the subscriber disconnects Internet access for a certain period within the allocated time. For example, if Joe purchases a one-hour time-to-finish account. He starts using the Internet for the first 20 minutes and then disconnects Internet access to go to a 20-minute meeting. Then he only has 20 minutes left on his account.
6.1.4Built-in Authentication
The built-in authentication method is useful if you do not have a RADIUS server. You can use the built-in subscriber database to manage the subscribers. With the built-in authentication, the VSG provides three sets of preconfigured scenarios that you can choose for easy and simple setup. For billing, use either a PMS or the built-in billing mechanism to set up accounting information.
6.1.5 RADIUS
The VSG supports Remote Authentication Dial-In user Service (RADIUS). By integrating RADIUS with the VSG, you can set up the subscriber database on the RADIUS server. In addition to subscriber information, the subscriber database may hold the Internet usage time period each subscriber is allocated. For example, when a subscriber logs in, the RADIUS server will send the time allocation information (such as session time-out) to the VSG, which uses this information to control the subscriber’s connection.
6.1.5.1 RADIUS Accounting
The VSG sends “accounting start” and “accounting stop” messages to the RADIUS server, which uses these messages to accurately track subscriber Internet usage.
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