The per-subscriber per-category credit can be obtained by several ways:
RADIUS during authentication process.
Static configuration - configured in the config>subscr-mgmt>category-map>category context.
Credit can be expressed by either
Volume
Time
The renewal of the credit using RADIUS authentication is triggered by credit exhaustion or (if configured) by depletion of the credit to exhausted-credit-threshold level. If this occurs, the system sends a RADIUS authentication message indicating the corresponding category and usage. The following are several possibilities for the RADIUS server response (as shown in Figure: Threshold configured/not configured):
No authentication response
The system installs out-of-credit action after the original credit has been used.
Authentication response with reject
The corresponding host is removed after the original credit has been used.
Authentication response with accept and no credit VSA included
The system installs out-of-credit action.
Authentication response with accept and credit VSA included
The credit is installed.
The new installed credit is reduced by the amount of credit consumed during credit renewal (in other words, between the start of the credit renewal and reception of an authentication-response). In case the new received credit is less than the credit consumed during credit renewal, then the out-of-credit-action is installed instead.
Authentication response with accept and credit VSA included
The out-of-credit installed. The new credit is always reduced by the amount of credit consumed in time between renewal has been initiated and authentication-respond has been received. In case of a negative result (the newly receive credit is smaller than the amount consumed in the meantime) the test is installed.
To identify that the specified RADIUS-auth request is related to credit renewal instead of plain authentication, the node includes empty credit VSAs, depending on categories which has been exhausted. The RADIUS server can identify which category has requested credit renewal.