There is a new link on the docuwiki under External tutorials:

http://openser.org/dokuwiki/doku.php/start

The project is located at:

http://frad-cdrtool.sourceforge.net

Thank you Dan-Cristian Bogos for making the FreeRADIUS-CDRTool Connector available to OpenSER users !!!

From his README:

FreeRADIUS-CDRTool is a freeradius module able to connect on the CDRTool prepaid engine through TCP API and implement a basic prepaid level for calls passing through OpenSER. I have created this module in my spare time and not being really expert in Python, so please watch it when u judge me ;).I am releasing this module free of any costs to be used or modified by anyone needs to (GPL), and I will try my best to support it from my own resources if this will be necessary, based on the respect I have for opensource software and community.

Functionality and concepts behind:

For calls being necessary to be authenticated, openser will send a Radius Access-Request packet which will contain the username and the destination for the call. As per configuration, freeradius will send those packets, sanitized by the digest module to python which will use the authorize function (again as per configuration). This function will query cdrtool as per described API (CDRTool PREPAID documentation) and return the necessary information back to OpenSER through the recommended way of SIP-AVP. The avps received will be available in openser as: callMaxDur and credit, where callMaxDur is the maximum duration the user is allowed to be connected with the destination and credit represents the amount of credit available at starting of the call. This info can be used later in an bbua able to timeout calls based on duration.

At the starting of the call, freeradius-cdrtool module will record the timestamps for Accounting-Start packet received from OpenSER in the memory, so it should spare some processing time without being necessary to query any database for this later.

When the call will be ended, OpenSER should inform FreeRADIUS about this, therefore freeradius-cdrtool beeing able to unlock the account as well as announce CDRTool to debit the necessary balance for the call from the user's account.

In the case of failed calls, freeradius-cdrtool will properly unlock the accounts without debiting any credit from user's accounts.