Description: China Telecom SIP specification of three parts, as well as China Telecom SIP supplementary and revision of norms, it is a comprehensive
File list (Check if you may need any files):
中国电信SIP规范第一部分_总体要求.pdf
中国电信SIP规范第三部分(信令流程).pdf
中国电信SIP规范第二部分(协议细则).pdf