3GPP 5G System and Key 5G technologies

3GPP 5G System and

Key 5G technologiesDr. Dionysis Xenakis

National and Kapodistrian University of Athens

Department of Digital Industry

Systems and Data Network Management (BSc)

[email protected]

Service-based architecture (high-

level) and 5G spectrum5G stakeholders, Service-based architecture (SBA), 5G spectrum

5/20/2021Dr. Dionysis Xenakis - Systems and Data Network Management - NKUA DIND.UOA.GR 2

5G system (5GS) enabling technologies

5G networks have been targeted to meet the requirements of a highly mobile and fully connected society

The coexistence of human-centric and machine type applications will define very diverse functional and performance requirements that 5G networks will have to support

5G System (5GS) fundamental pillars to support the heterogeneous key performance indicators (KPIs) of the new use cases in a cost-efficient way

Service-based architecture

Software-Defined Networking (SDN)

Network Function Virtualization (NFV)

End-to-end (E2E) network slicing

5G New Radio (NR) technologies

The 5GS gives mobile network operators the unique opportunities to offer new services to consumers, enterprises, verticals, and third-party tenants


Key 5G stakeholders (3GPP)

Virtualization, standard interfaces and protocols, open APIs shall enable

manufacturers, solution integrators, network and service providers, and Small

and Medium-sized Enterprises (SMEs) to efficiently compete and cooperate,

SMEs shall provide technological solutions which will be compatible with the

overall system

e.g., new hardware components in the infrastructure, or software components in

the Management and Organization layers

Mobile Network Operators (MNOs) and infrastructure providers shall create

tailored slices with specific functionalities as well as Over-The-Top (OTT)

applications and services to address requirements of vertical industries



Service Customer (SC)

Uses services that are offered by a Service Provider (SP). In the context of 5G, vertical industries are considered as one of the major SCs.

Service Provider (SP)

Comprises three sub-roles, depending on the service offered to the SC

Communication Service Provider offering traditional telecom services,

Digital Service Provider offering digital services such as enhanced mobile broadband and IoT to various vertical industries

Network Slice as a Service (NSaaS) Provider offering a network slice along with the services that it may support and configure. SPs design, build and operate services using aggregated network services

Network Operator (NOP)

Orchestrates resources, potentially from multiple virtualized infrastructure providers (VISP)

Uses aggregated virtualized infrastructure services to design, build, and operate network services that are offered to SPs



Virtualization Infrastructure Service Provider (VISP)

Provides virtualized infrastructure services and designs, builds, and operates virtualization infrastructure(s)

The infrastructure comprises networking (e.g., for mobile transport) and computing resources (e.g., from computing platforms)

Data Centre Service Provider (DCSP)

Provides data center services and designs, builds and operates its data centres.

VISP vs DSCP

DSCP offers “raw” resources (i.e., host servers) in rather centralized locations and simple services for consumption of these raw resources

A VISP offers access to a variety of resources by aggregating multiple technology domains and making them accessible through a single API




3GPP 5G general requirements and

concepts

Separate the User Plane (UP) functions from the Control Plane (CP) functions

Allowing independent scalability, evolution and flexible deployments e.g. centralized location or distributed (remote) location.

Modularize the function design

e.g. to enable flexible and efficient network slicing

Define procedures (i.e. the set of interactions between network functions) as services, so that their re-use is possible

Enable each Network Function to interact with other NF directly if required

The architecture does not preclude the use of an intermediate function to help route Control Plane messages (e.g. like a DRA).

Minimize dependencies between the Access Network (AN) and the Core Network (CN)

The architecture is defined with a converged core network with a common AN - CN interface which integrates different Access Types e.g. 3GPP access and non-3GPP access.


5GS high-level Architecture by 5GPPP [5]


Resources and Functional Level

Physical resources

Including both access and core network physical resources, backhaul resources and computing resources (cloud and edge)

Physical network resources combine physical resources belonging to different Radio Access Technologies (RATs)

Cloud / central cloud resources provide well-organized powerful resources in distributed data centers

Edge cloud resources include loosely coupled yet proximal resources to the end terminals, enabling MEC and fog computing

Different roles for edge vs cloud physical resources (towards reduced layer)

All physical resources are tied together using SDN-based high-data rate control, to become virtually separated and programmable using SDN principles


Network level

Decoupled from its physical resources and uses logical functions/separation to build resources for the Service layer

Responsible for creating network slices in response of requests from the Service layer

A network slice is an e2e network encompassing multiple logical networks and running on-top of the Resources and Functional Level

Similar to VLAN but integrates computing, storage and logical functions

Can be configured to meet service needs (broader concept than QoS – resource isolation and network within a network)


Service Level

Higher level in the

architecture

Creates service

instances based on

Service License

Agreements

Interfaces external

third parties

Handles isolated

slices

Dr. Dionysis Xenakis - Systems and Data Network Management - NKUA DIND.UOA.GR 5/20/2021 12

E2E Service Operations – Lifecycle

Management

Dr. Dionysis Xenakis - Systems and Data Network Management - NKUA DIND.UOA.GR

In 5G, many things will be offered as a service, including infrastructure, a platform, or software

Network slicing shall satisfy the need for customised, service-specific combinations of service components and network functions in all of the network segments

Service lifecycle management (LCM) tools are enabled by Service Development Kits (SDKs)

Using SDKs, services can be reconfigured, or new service versions can be created

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5G Architecture – Migration Options

Option 1: Legacy LTE SA with EPC connected

Option 2: 5GS SA with 5GC connected

Option 3: 5G NSA LTE assisted with EPC connected


5G Architecture – Migration Options

Option 4: NSA 5G NR assisted with 5GC connected

Option 5: 5G SA Rel. 15 with 5GC connected

Option 6: SA 5G radio connected to EPC

Option 7: NSA LTE assisted with 5GC connected

Option 8: NSA 5G NR assisted with EPC connected


5G Spectrum

Billions of devices shall require access to the 5G spectrum

ITU responsible for setting worldwide bands for wireless communications

Depending on availability of spectrum per country

M2M, IIoT, V2X and eMBB urge for the utilization of new bands

Three types of bands for 5G

Low Bands (<1GHz)

Limited spectrum (capacity) typically 800MHz, 900 MHz, 5G will have 600,700MHz (current analog TV broadcast)

Very good propagation characteristics (penetrates buildings)

Ideal for rural, suburban and through-building (deep indoor) network coverage

Currently used for mobile broadband and IoT by 3GPP


5G Spectrum

Three spectrum bands

Medium bands (1-2.6 and 3.5-6GHz)

5G bands typically in 3.5GHz and 4GHz

Acceptable but not as good propagation characteristics as compared to lower bands

Good balance between latency, throughput and distance

eMBB, URLLC and some IoT applications exist

High bands (6GHz to 100GHz)

Subject to absorption by physical phenomena (oxygen, buildings, rain, etc.)

mmWave communications enable dense deployments of extremely high thoughput, low latency

Large pool of spectrum available (enable fiber-like capacity over wireless)

IoT applications and Fixed Wireless Access (FWA)


5G Spectrum

[6]

The engineering of a MW or mmW link involves finding the optimal combination of link length, capacity, frequency band and availability.

The physics of radio waves propagation determine the relation among capacity, availability and link length

Licensed and unlicensed spectrum operation considered by 3GPP

Dynamic Spectrum Sharing (DSS) technology

Enable the 5G system to share/co-utilize mid bands assigned to 3G/4G systems

Spectrum availability is scarce in such bands

Split spectrum between two different networks, dynamically changing based on per system load


5G Spectrum [6] – MW/mmWave bands


MW and mmW Transport Network

Topology [6]

The penetration of fiber to the edge of the network and the densification of sites

have two main effects:

Shortening of chains of cascaded radio links, approaching the limit of one radio link to

the fiber

Increase of the number of links originating from a hub site in a star-like topology

Tail links are used to connect just one terminal mobile site

Aggregation links carry the traffic of different terminal sites

Meshed topology

Radio links are the fastest and most efficient way to assure the secondary connection,

covering the requirements related to network slicing, per path and per service

Link protection with media differentiation over the shortest/fastest path between

adjacent sites


Topology evolution in the macro cell backhaul

network


5G enabling technologies (5GC)SDN, NFV and network slicing


Software Defined Networks and Network

Function Virtualization

Play central roles in the e2e implementation of 5G

Enablers for software-centric networking and service-

based architecture

NFV enables Network services (NS) to be

implemented by dynamically deploying

virtualized network functions (VNFs) and

programming their connectivity

Can be deployed in different locations

and centers, either at the RAN, or the

CN

Adjusted according to service type and

requirements

SDN provides modularity and programmability at the

Network Operating System (NOS) level


SDN technology overview

Traditional networks

Network includes dedicated devices (switches, routers, etc.)

Network control functions implemented through dedicated hardware that includes

specific integrated circuits and proprietary software

Some compatibility issues may be faced due to multiple vendors

Control logic is coupled to the data transferred

A group of devices cannot be easily re-programmed with one operation

SDN enables control/data plane separation

Software-based control and fully programmable devices

Network flows can be controlled dynamically using reprogramming


SDN technology overview

SDN enables control/data plane separation

Devices are viewed as infrastructure nodes that deploy forwarding/processing,

handling only the data plane

A control layer is introduced to enable the implementation of a logically central

controlled that handles lobotomized infrastructure nodes

Application layer consists of business, network and other applications

A management layer may exist

Northbound interface: application layer to control layer

Southbound interface: control layer to data plane (infrastructure nodes)


SDN

architecture

Infrastructure layer only forwards packets

Control layer takes decisions on algorithms and policies for forwarding packets

Gives instructions in terms of rules to the infrastructure layer

Application layer interacts with controller to ask for resources and set requirements to the control layer

Specific protocols are used for NB/SB interfaces (APIs)

OpenFlow* protocol for SB API


References

[1] https://www.etsi.org/technologies/5g

[2] EURO-5G, D2.6: Final report on programme progress and KPIs, https://5g-ppp.eu/wp-content/uploads/2016/02/BROCHURE_5PPP_BAT2_PL.pdf

[3] A. Dogra, R. K. Jha and S. Jain, "A Survey on beyond 5G network with the advent of 6G: Architecture and Emerging Technologies," in IEEE Access, doi: 10.1109/ACCESS.2020.3031234.

[4] 5G PPP Architecture Working Group, “View on 5G Architecture”, Version 3.0, February 2020.

[5] ETSI TS 23 501, ”5G; System Architecture for the 5G System”, V15.2.0 (2018-06)

[6] ETSI White Paper No. 25, “Microwave and Millimetre-wave for 5G Transport“, First edition – February 2018. ISBN No. 979-10-92620-19-1

[7] ETSI GS NFV 002 (V1.2.1), “Network Functions Virtualization (NFV); Architectural Framework”, Dec 2014

[8] 5GPPP Architecture Working Group, “View on 5G Architecture”, Version 2.0, Dec. 2017

[9] https://www.cisco.com/c/en/us/products/collateral/wireless/packet-core/data-sheet-c78-741416.html

[10] 3GPP TS 23.501 , “System architecture for the 5G System (5GS)”, V15.11.0, Rel.15, Sept 2020.

[11] https://5g.security/5g-technology/5g-core-sba-components-architecture/


https://www.etsi.org/technologies/5g

https://5g-ppp.eu/wp-content/uploads/2016/02/BROCHURE_5PPP_BAT2_PL.pdf

https://www.cisco.com/c/en/us/products/collateral/wireless/packet-core/data-sheet-c78-741416.html

3GPP 5G System and Key 5G technologies

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