Communication Networks: 2G to 4G Overview

The first generation of mobile networks used analog transmissions for voice calls only. It offered limited data capabilities. Think of it like a walkie-talkie with very limited range.

The second generation of mobile networks, also known as GSM, introduced digital transmission, allowing for better voice quality, encryption, and basic data services like SMS text messaging.

A standardized mobile phone technology widely adopted across the world, offering digital voice and data services. It utilizes SIM cards for user identification.

A mobile device, also known as a handset, equipped with a SIM card and a radio antenna. It communicates with the network via the Base Transceiver Station (BTS).

A small, removable card containing the subscriber's account information, including their phone number and network settings. It serves as the primary interface between the phone and the network.

A network infrastructure component that handles radio transmissions between the mobile station (MS) and the network. It includes radio transceivers for communication and manages the radio link protocols.

They manage the radio resources of one or more BTSs. They handle functions like radio channel setup, frequency hopping, and handovers between BTSs.

It's the central part of the network switching system (NSS) responsible for call routing, call setup, and basic switching. It also coordinates with other MSCs and handles multiple BSCs.

It handles calling routing, call setup, and basic switching. It also coordinates with other MSCs and handles multiple BSCs.

The Base Station Subsystem (BSS) comprises the Base Transceiver Station (BTS) and Base Station Controller (BSC). This part of the network infrastructure is responsible for radio communications between the mobile station and the network.

A database responsible for storing and managing information about subscribers, including their profiles, locations, and activity status.

A temporary database that keeps track of mobile devices that have entered its coverage area. It updates its information from the HLR as needed.

A database that verifies the validity of mobile devices on the network, allowing, denying, or restricting their access.

A secure database that stores a copy of the secret key found in each subscriber's SIM card, used for authentication purposes.

A packet-based data service within the GSM network, offering data rates from 56 to 114 kbps. It leverages existing 2G infrastructure.

The component responsible for authentication, mobile registration, mobility management, and charging for GPRS mobile users.

A gateway between the GPRS network and external networks. It handles routing, charging, and security for GPRS traffic.

The 3rd generation of cellular mobile technology, offering significantly faster download speeds through a new radio access network.

The new radio access network in 3G technology. It replaces the BTS towers with NodeBs, providing higher data rates.

A component within UTRAN that manages the radio network in 3G, controlling communication between mobile devices and the network.

The Evolved Packet Core (EPC) is a unified network architecture used in 4G (LTE) systems. It combines voice and data services over an IP network, treating voice as just another IP application. Think of it as a central hub that manages both voice and data traffic.

The Home Subscriber Server (HSS) acts as a central database in the EPC. It stores information about all the network operator's subscribers, including their details, services, and preferences. It's like the central directory for all users on the network.

The Mobility Management Entity (MME) is a key component of the EPC that manages user sessions, authenticates users, and tracks their location across the network. Think of it as a traffic controller for user movement and communication.

The Serving Gateway (SGW) acts as a router in the EPC, forwarding data between the base station and the PDN gateway. It connects to other network infrastructure elements for previous generations. Think of it as a bridge connecting different parts of the network.

The Packet Data Node Gateway (PGW) is the interface between the LTE network and other packet data networks. It controls the quality of service (QoS) and performs deep packet inspection (DPI). Think of it as a gatekeeper that manages data flow and security.

The Policy and Charging Rules Function (PCRF) manages data flow detection, policy enforcement, and flow-based charging in the EPC. Think of it as a supervisor that sets policies and ensures fair usage and billing.

In 4G (LTE), User Equipment (UE) refers to the mobile station, the device that connects to the network. It replaces the term 'Mobile Station' (MS) used in older generations. Think of it as a more general term for any device that connects to the LTE network.

In 4G (LTE), voice calls are treated as IP applications, similar to other data services. This means that voice calls are transmitted over the internet protocol, instead of separate circuit domains like in older generations. Think of voice calls as just another type of data in 4G.

The Evolved Packet Core (EPC) architecture in 4G (LTE) networks offers advantages like improved quality of service for data applications, enhanced security, and increased network efficiency. It also provides flexibility for future network evolution and integration.

The transition to 4G (LTE) with EPC architecture signifies a significant shift in mobile network architecture. This change has enabled the seamless integration of voice and data services over IP, which has paved the way for new services and capabilities in mobile communications.