Fundamentals of Network Planning and Optimisation 2G/3G/4G, 2nd Edition

73G Core Network Planning and Optimisation

7.1 Basics of Core Network Planning

Core network planning in a 3G (WCDMA) system consists of both circuit core and packet core planning.

7.1.1 Scope of Core Network Planning

The scope of core network planning includes dimensioning of network elements such as MGW, MSC (and VLR) and HLR (and AC/EIR) from the CS side, while the PS core will include SGSN, GGSN along with interfaces (Figure 7.1).

Figure 7.1 Scope of core network planning in a 3G system (WCDMA).

7.1.2 Network Elements in the Core Network

Network elements in the 3G core network remain almost the same as seen in the previous chapters on core networks, except that a couple of new concepts are added: MSC and MGW (media gateway). These are briefly explained below.

According to the 3GPP Rel4, both the control and user plane traffic gets separated, with MSC and MGW handling the control plane and user plane traffic, respectively.

MSC, also known as MSC Server in 3GPP Rel4, handles the call and mobility control function for CS traffic generated by the registered subscribers, incoming calls from other networks, mobile‐originated calls, and mobile‐terminated calls. Apart from this, it is also responsible for signalling conversion (user‐to‐network signalling converted to network‐to‐network signalling). The MSC (server) is also responsible for controlling the MGW. The MSC (server), ...