... tin chung (generic media - G), s DTMF (D), handset (H), ng dõy (line - L), trung k (trunk - T), mỏy ch truy nhp mng (network access server - N), mỏy ch thụng bỏo (announcement server - A) Tuy nhiờn ... NGN 1.4.1 Cu trỳc chc nng Mng NGN bao gm cỏc lp chc nng sau [5]: - Lp truy nhp (Access); - Lp chuyn ti (Transport); - Lp iu khin (Control); - Lp ng dng (Application); - Lp qun lý (Management) ... s h tr hot ng cỏc thnh phn khỏc ca mng NGN nh: Signaling Gateway (SG), Media Gateway (MG), Media Server (MS), Application Server (AS)/Feature Server (FS) [5] Trong ú Media Gateway l thnh phn...