Private Telecommunication Network (PTN); Specification, functional models and information flows; Call offer supplementary service
专用电信网(PTN);规范、功能模型和信息流;呼叫提供补充业务
Contains stage 1 and stage 2 description of the call offer supplementary service. See ECMA DTR/ECMA-0002 (ECMA-TR/SVC) for a description of the call offer supplementary service. See ENV 41 005 for definition of stage 1 and 2.