(BQ) Part 1 book "Mobile networks architecture" has contents: The NGN, the EPS Network (Network architecture, the radio interface, communication management), the IMS network (The SIP, the IMS architecture, communication management) | Chapter 4 The NGN The basic functions of the MSC (Mobile-services Switching Center), which provides a service in CS (Circuit Service) mode, are circuit switching, signaling processing and mobility management (MM). Interconnection between the entities of the Network Sub-System is achieved by a SDH (Synchronous Digital Hierarchy) transmission network. The NGN (Next Generation Network) is an evolution of the NNS core network. Signaling processing and MM are provided by a stand-alone entity, the MSC Server. The interconnection between the entities of the NGN is operated by the same Internet Protocol (IP) network deployed for the GSS (GPRS Sub-System). Section explains the architecture of the NGN and describes the components, the MSC Server and the MGW (Multimedia GateWay) and SGW (Signaling GateWay) providing the interfaces with the PLMN (Public Land Mobile Network) or PSTN (Public Switched Telephone Network) third-party networks, BSS (Base Station Sub-system) or UTRANs (UMTS Terrestrial Radio Access Networks). Section also introduces the protocol architecture implemented for signaling and media transport on an IP network, for the control of the gateways by the MSC server and for dialog between the MSC Servers. Section describes the procedures concerning the establishment of a communication during an incoming or outgoing call, release of the communication and management of the mobile on the move (handover). 156 Mobile Networks Architecture . Network architecture . Network components The MSC and GMSC (Gateway MSC) nodes are broken down into two entities: the MSC or GMSC Server; and the MGW and SGW (Figure ). Figure . The NGN architecture The MSC Server ensures the processing of MM and communication management functions. Like the MSC, it is connected to the Visitor Location Register database to take into account the mobile data stored in the HLR (Home Location Register) database. The MSC Server terminates the signaling exchanged with the
