2. Voice over IP in new convergent architectures

2.1 Next-generation network (NGN)

• NGN network

  A Next Generation Network (NGN) is based on a single transport network using IP packet switching, enabling operators to eventually disengage from circuit-switched transport networks (PSTN network and circuit domain of the mobile core network) as well as from the SS7 network. In the target scenario, the operator has a transport network offering customers all traditional telecoms services, as well as new, innovative services, whatever the access network: fixed wireline deployed at home (ADSL, cable, FTTH) or in the enterprise (LAN), wireless (WLAN, WiMax) or mobile (UMTS, CDMA2000, LTE/SAE). The NGN network enables operators to achieve economies of scale on equipment, since the same infrastructure...