Method for billing in a telecommunications network

A computer-readable medium having computer executable instructions for performing a method for placing a call between a first session initiation protocol (SIP) device and a second SIP device, the computer-readable medium comprising:

• one or more instructions to receive, from the first SIP device, a SIP call request message for establishing a call with the second SIP device;
• one or more instructions to identify a call feature that is enabled for the second SIP device, the call feature identifying a non-SIP device to receive the call;
• one or more instructions to identify, based on the identified call feature, a party associated with the second SIP device as a party responsible for paying for the call only when the identified call feature identifies the non-SIP device to receive the call;
• one or more instructions to determine whether a database includes a client billing tag that corresponds to the party associated with the second SIP device;
• one or more instructions to permit the call to be established when the database includes the client billing tag;
• and
• one or more instructions to deny the call when the database does not include the client billing tag.

A system, comprising:

• a SIP server to:
• receive a SIP call request message that requests that a call be established from a first SIP device to a second SIP device,
• identify a calling feature that is enabled for the second SIP device, the calling feature identifying a non-SIP device to receive one or more calls intended for the second SIP device,
• determine an authentic originating client based on the calling feature,
• obtain a client billing tag that identifies the authentic originating client as a party responsible for paying for the call;
• and
• a network gateway, coupled to the SIP server, to provide at least one of the first SIP device or the second SIP device conditional access to a public switched telephone network.