In W-CDMA (Wideband Code Division Multiple Access), CN stands for Core Network. The Core Network is a fundamental component of a W-CDMA cellular network, playing a crucial role in the overall communication and management of mobile services. Let’s explore the key aspects of the CN in W-CDMA:
1. W-CDMA Network Architecture:
- W-CDMA is a third-generation (3G) mobile communication standard that uses CDMA principles for wireless communication.
- The network architecture of W-CDMA is divided into two main components: the Radio Access Network (RAN) and the Core Network (CN).
2. Core Network (CN) Components:
- The Core Network encompasses various components that handle the core functionalities of mobile communication services. These components include:
- Mobile Switching Center (MSC):
- The MSC is a central component in the Core Network responsible for call switching and control.
- It connects calls between mobile devices within the same network or to external networks, ensuring efficient call routing.
- Gateway GPRS Support Node (GGSN):
- The GGSN is a key element for General Packet Radio Service (GPRS) data services in W-CDMA networks.
- It acts as a gateway between the W-CDMA network and external packet-switched networks, such as the internet.
- Serving GPRS Support Node (SGSN):
- The SGSN is responsible for managing the mobility and session information of mobile devices.
- It plays a critical role in handovers and ensures seamless connectivity as devices move between different cells within the network.
- Home Location Register (HLR) and Visitor Location Register (VLR):
- The HLR stores subscriber information, including user profiles and subscription details.
- The VLR is a temporary database that stores information about subscribers currently within the jurisdiction of a specific MSC.
- Authentication Center (AUC):
- The AUC is responsible for authenticating and verifying the identity of mobile devices before granting access to the network.
- It enhances network security by ensuring that only authorized devices can connect.
- Mobile Management Entity (MME):
- In the context of Long-Term Evolution (LTE) networks, which evolved from W-CDMA, the MME is responsible for the control plane functions related to mobility and session management.
3. Functions of the Core Network (CN) in W-CDMA:
- Call Setup and Routing:
- The MSC in the Core Network is responsible for setting up and managing voice calls within the W-CDMA network.
- It ensures efficient routing of calls to their intended destinations.
- Data Services Handling:
- The GGSN and SGSN components are involved in handling data services, including internet access and packet-switched communication.
- They enable W-CDMA networks to provide a range of data services to mobile users.
- Subscriber Management:
- The HLR and VLR play a crucial role in managing subscriber information, ensuring that the network has up-to-date information about each mobile device and its associated services.
- Authentication and Security:
- The AUC contributes to the security of the W-CDMA network by authenticating mobile devices and protecting against unauthorized access.
- Mobility Management:
- The SGSN and, in LTE networks, the MME manage the mobility of mobile devices within the network.
- They facilitate handovers and ensure that devices can seamlessly move between different cells without losing connectivity.
4. Evolution to LTE and 5G:
- While W-CDMA networks have been succeeded by Long-Term Evolution (LTE) and 5G technologies, the principles of the Core Network (CN) remain relevant.
- The architecture and functions have evolved in subsequent generations, but the core elements of call management, data services, subscriber management, and security persist.
5. Global System for Mobile Communications (GSM) Integration:
- W-CDMA networks often coexist with GSM networks, and the Core Network components facilitate interoperability between these different technologies.
- This integration allows for seamless communication between devices on W-CDMA and GSM networks.
In summary, the Core Network (CN) in W-CDMA is a central element that manages essential functions, including call setup, data services, subscriber management, authentication, and mobility. It plays a pivotal role in providing reliable and secure mobile communication services within the W-CDMA network architecture.