Sign in Subscribe

core network in telecom

Last updated on 


The core network in a telecommunications system is the central part responsible for managing and controlling network resources and services. It plays a crucial role in facilitating communication between different users and devices within a telecom network. The core network is typically divided into several key components, each serving specific functions. Below, I'll explain the core network components and their technical details:

  1. Mobile Switching Center (MSC):
    • Function: The MSC is a central component in a mobile network, responsible for call switching, call setup, and call release. It connects calls between mobile users within the same network or to external networks.
    • Technical Details: MSCs use signaling protocols such as Signaling System 7 (SS7) to exchange control information and establish connections. They also interface with the Home Location Register (HLR) and Visitor Location Register (VLR) for user authentication and location tracking.
  2. Home Location Register (HLR):
    • Function: The HLR is a database that stores subscriber information, including user profiles, subscription details, and current locations. It is the primary database for subscriber-related information.
    • Technical Details: HLRs use databases and protocols to store and retrieve subscriber data. It communicates with the MSC for call routing and user authentication.
  3. Visitor Location Register (VLR):
    • Function: The VLR is a temporary database that stores information about subscribers currently within the coverage area of a particular MSC. It helps in providing seamless services to roaming users.
    • Technical Details: VLRs communicate with the HLR to retrieve subscriber information when a user roams into a new area. This information is crucial for call routing and maintaining service continuity.
  4. Gateway Mobile Switching Center (GMSC):
    • Function: The GMSC is responsible for routing calls between different networks. It acts as a gateway for calls originating from or destined for external networks.
    • Technical Details: GMSCs use various signaling protocols to communicate with other networks and determine the routing path for calls.
  5. Authentication Center (AUC):
    • Function: The AUC is responsible for authenticating the identity of mobile subscribers. It helps in preventing unauthorized access to the network.
    • Technical Details: AUCs use encryption algorithms and authentication tokens to verify the identity of users during the registration process.
  6. Equipment Identity Register (EIR):
    • Function: The EIR is responsible for maintaining a list of valid mobile device identities and identifying stolen or unauthorized devices.
    • Technical Details: EIRs use databases and protocols to store and manage device identities. They play a crucial role in ensuring the security of the network.
  7. Gateway GPRS Support Node (GGSN) and Serving GPRS Support Node (SGSN) (for 3G/4G/5G networks):
    • Function: These components manage data services in mobile networks, providing connectivity to the internet and other external networks.
    • Technical Details: GGSNs handle the interconnection between the mobile network and external packet-switched networks, while SGSNs manage the mobility and session management for data services.