5G network architecture
The main "chips" characterizing the fifth generation mobile communication networks are:
Ultra-broadband mobile access (enhanced Mobile Broadband, eMBB),
Ultra-reliable communication with low latency (Ultra-Reliable and Low Latency Communications, URLLC),
Mass connection of various sensors and devices from the world of "Internet of Things" (massive Machine Type Communications, mMTC).
5G network architecture
3GPP TR 38.913 defines the following key metrics for 5G networks:
20 Gbps downlink peak data rate (spectral efficiency 30 bps/Hz);
10 Gb/s peak uplink data rate (15 bps/Hz spectral efficiency);
Minimum delay 4 ms for eMBB services and 0.5 ms for URLLC services
The maximum density of Internet-of-Things devices connected to the network in urban areas is 1,000,000 devices/km2;
Autonomous operation of devices from the world of "Internet of Things" without recharging the battery for 10 years;
Support of mobility at the maximum speed of movement of objects of 500 km/h.
These indicators are sometimes incompatible and even mutually exclusive.
Therefore, only certain services with certain indicators will be available to different devices at different points in time (within the framework of the Network Slicing concept).
The key principles of the 5G network architecture are as follows:
The division of network nodes into elements that provide the operation of the protocols of the “user plane” (UP - User Plane) and elements that provide the operation of the protocols of the “control plane” (CP - Control Plane), which greatly increases the flexibility in terms of scaling and deployment (allowing centralized and decentralized placement of individual component network nodes).
Separation of network elements into network layers (Network Slicing), based on the services provided to specific groups of end users.
Implementation of network elements in the form of virtual network functions - VNF (Virtual Network Functions).
Support for simultaneous access to centralized and local services, which allows you to implement the concepts of cloud (fog computing) and edge (edge computing) computing.
Definition of a convergent architecture that combines various types of access networks (AN - Access Network) - 3GPP (New Radio - NR) and non-3GPP (WiFi, etc.) with a single core network (CN - Core Network).
Regardless of the type of access network, it support for unified algorithms and authentication procedures.
Support for stateless network functions, where the computing resource is separated from the storage resource.
Support for roaming with traffic routing both through the home network (Home routed) and with local landing (Local breakout) in the guest network (VPLMN).
In the 5G architecture, the interaction between network functions is represented in two ways:
Service-oriented, when some network functions (for example, AMF) allow other authorized network functions to access their services.
Interface, which indicates what kind of interaction exists between the services of network functions, described as a point-to-point interaction (for example, the N11 interface) between any two network functions (for example, AMF and SMF).
Network functions on the 5G control plane should only use service-oriented interfaces for their interaction.
Thank you.
