H.323 Non-2833 Interworking with SIP

RFC 2833 and the SIP INFO method can be used for conveying DTMF information for SIP based-services. (RFC 2833 is the most widely used.) To provide end-to-end DTMF for SIP devices supporting RFC-2833 interworking with H.323 devices that do not, an RFC 2833 to H.323 UII interworking function is provided.