Patent ID: 8311193

Claim:
A charging method for Group Main Line (GML) service, comprising: receiving a call initiated by an extension of the GML and triggering an Intelligent Network (IN) service; checking a called number of the call; processing the call initiated by the extension as a call collectively paid by the GML, if there is a predefined prefix for a group service before the called number, and processing the call initiated by the extension as a call not paid by the GML, if the predefined prefix for the group service is not present, wherein the step of processing the call initiated by the extension as the call collectively paid by the GML comprising: generating by a service control point (SCP), a call record for the extension which initiated the call, and indicating in the call record that the initiated call is paid by the GML; issuing by the SCP, a picking-call record instruction to an end office accessed by the extension; and marking by the end office, the call record for the extension recorded locally with a special charging flag, according to the picking-call record instruction.