Mechanism of Audio-Text Mode Assignment on SIP-based Internet Telephony System

Next to the binary-based H.323 signaling protocol for Internet telephony service developed by the Telecommunication World (ITU-T), a more lightweight text-based protocol was deemed necessary to address the specific needs of the Internet World. The session initiation protocol (SIP) was introduced in the IETF and has meanwhile gained maturity and support. The SIP-based Internet telephony service guarantees the user mobility. If SIP user is the place where the Internet connection is possible, it anytime can use a Internet telephony service in a where. Internet telephony communication with the user who is connected Internet softphone without headset or deaf people or speech-impaired people is difficult. Therefore, in this paper, we suggest mechanism of audio-text mode assignment on SIP Internet telephony system.