Call Control is an application that is used in combination with OpenSIPS and CDRTool to limit calls based on prepaid credit and globally specified time limits. This software is licensed according to the GPL version 2.


Call Control is maintaining a timer for each session and sending BYE messages to both SIP end-points, if the session exceeds its maximum session limit or if the Call Control process receives a command to forcefully close the call from outside.

Prepaid overview



  • Maximum simultaneous sessions per SIP accounts
  • Detect duplicate Call-IDs
  • Parallel sessions using one balance per subscriber
  • Support for sessions that have timeout without BYE
  • Support for sessions that have timeout for media (using MediaProxy)
  • Manual session stop from server terminal
  • Overview of ongoing sessions in the web page or server terminal
  • Graceful restart without loosing track of sessions
  • Detailed logging of all performed actions using syslog
  • Web page provisioning for prepaid accounts (using CDRTool)