KSR.info(
            '[rtp] msg has sdp: {}'.format(
                str(KSR.textops.has_body_type("application/sdp"))
            )
        )

        # engage rtp engine
        if KSR.is_INVITE() or KSR.is_UPDATE() and KSR.textops.has_body_type(
                "application/sdp") > 0:
            KSR.info('[rtp] RTP ENGAGE RELAY')
            if to_fs:
                self.engage_rtpengine(internal=True)
            else:
                self.engage_rtpengine()