Disaggregation of 5G Core (5GC) Network

When talking about mobile networks, we generally talk about disaggregation and virtualization of the RAN rather than the core. The 5G Core Network was also designed with disaggregation in mind, supporting service-based architecture (SBA) where Network Functions (NFs) are modular and can be deployed as microservices.

The 5G Core (5GC) is the foundation for Standalone 5G (5G SA) networks where the end users can experience the power of 'real' 5G. A newly published forecast report by Dell’Oro Group pointed out that the Mobile Core Network (MCN) market 5-year cumulative revenue forecast is expected to decline 10 percent (2024-2028). The reduction in the forecast is caused by severe economic headwinds, primarily the high inflation rates, and the slow adoption of 5G SA networks by Mobile Network Operators (MNOs).

While most people think of 5G Core Network as a single entity, in reality it contains many different network functions that can be supplied by different vendors. One way to select the vendors is based on grouping of NFs based on functionality as shown in the picture above. Here we have categorised them into User Plane & Mobility, Subscriber Data Management, Routing & Selection, and Policy & Charging. 

An example of of this disaggregation can be seen in the image above where Telenor worked with partners to build a truly multi-vendor, 5G core environment running on a vendor-neutral platform. According to their announcement: 

“The main component of 5G-SA is the 5G mobile core, the ‘brain’ of the 5G system. Unfortunately, most 5G core deployments are still single vendor dependent, with strong dependencies on that vendor’s underlying proprietary architecture. This single-vendor dependency can be a killer for innovation. It restricts open collaboration from the broader 5G ecosystem of companies developing new technology, use cases, and services that the market expects,” explains Patrick Waldemar, Vice President and Head of Technology in Telenor Research.

As an industry first, Telenor, along with partners, have established to build a truly multi-vendor, 5G core environment running on a vendor-neutral platform. The multi-vendor environment consists of best of breed Network Functions from Oracle, Casa-Systems, Enea and Kaloom, all running on Red Hat Openshift, the industry’s leading enterprise Kubernetes platform.

“To protect the 5G infrastructure from cyber threats, we deployed Palo Alto Networks Prisma Cloud Compute, and their Next Generation Firewall is also securing Internet connectivity for mobile devices. Red Hat Ansible Automation Platform is being used as a scalable automation system, while Emblasoft is providing automated network testing capabilities. The 5G New Radio (NR) is from Huawei,” says Waldemar.

In their whitepaper on "How to build the best 5G core", Oracle does a very similar grouping of the NFs like the way I have shown at the top and highlights what they supply and which partner NFs they use.

When the mobile operator Orange announced the selection of suppliers for their 5G SA networks in Europe, the press release said the following:

Orange has chosen the following industrial partners:

• Ericsson’s 5G SA core network for Belgium, Spain, Luxembourg and Poland
• Nokia’s 5G SA core network for France and Slovakia 
• Nokia’s Subscriber Data Management for all countries
• Oracle Communications for 5G core signaling and routing in all countries

I was unable to find out exactly which NFs would be supplied by which vendor but you get an idea.

Finally, I have depicted four scenarios for deployment and which Cloud Native Environment (CNE) would be used. In a single vendor core, the CNE, even though from a third party, could belong to either the vendor themselves (scenario 1) or may be suggested by the operator (scenario 2). 

In case of a multi-vendor deployment, it is very likely that each vendor would use their own CNE (scenario 4) rather than one suggested by the operator or belonging to the lead vendor (scenario 3).

If you have been involved in trial/test/deployment of a multi-vendor 5G Core, would love to hear your feedback on that as well as this post.

Related Posts: 

• 3G4G: 3GPP 5G Specifications
• 3G4G: Control and User Plane Separation of EPC nodes (CUPS)
• 3G4G: 5G Service Based Architecture (SBA)
• The 3G4G Blog - Opinion: What is "Real 5G" or "True 5G"
• The 3G4G Blog: The Politics of Standalone vs Non-Standalone 5G & 4G Speeds 

Authentication and Key Management for Applications (AKMA) based on 3GPP credentials in the 5G System (5GS)

3GPP Release 17 introduced a new feature called AKMA (Authentication and Key Management for Applications), the goal of which is to enable the authentication and generation of application keys based on 3GPP credentials for all UE types in the 5G System, especially IoT devices, ensuring to bootstrap the security between the UE and the applications in the 5G system.

3GPP TR 21.917 has an excellent summary as follows:

Authentication and key management for applications based on 3GPP credential in 5G (AKMA) is a cellular-network-based delegated authentication system specified for the 5G system, helping establish a secure tunnel between the end user and the application server. Using AKMA, a user can log in to an application service only based on the 3GPP credential which is the permanent key stored in the user’s tamper-resistant smart card UICC. The application service provider can also delegate the task of user authentication to the mobile network operator by using AKMA. 

The AKMA architecture and procedures are specified by SA3 in TS 33.535, with the related study showing how its general principles are derived documented in TR 33.835. The AKMA feature introduces a new Network Function into the 5G system, which is the AKMA Anchor Function (AAnF). Its detailed services and API definitions are specified by CT3 in TS 29.535. Earlier generations of cellular networks include two similar standards specified by SA3, which are generic bootstrapping architecture (GBA) and battery-efficient security for very low throughput machine type communication devices (BEST). Since the AKMA feature is deemed as a successor of these systems, the work is launched by SA3 without the involvement of stage 1.

In the latest issue of 3GPP Highlights Magazine, Suresh Nair, 3GPP Working Group SA3 Chair, Saurabh Khare & Jing Ping (Nokia) has explained the AKMA procedure. The article is also available on 3GPP website here. The article lists the following as AKMA advantages:

• Since the AKMA framework uses authentication and authorization of the UE leveraging the PLMN credentials stored on the USIM, this becomes as strong as the network primary authentication and subsequent keys derived further to UE and Application Function (AF) interface.
• The Application Functions can leverage the authentication service provided by the AKMA Anchor Function (AAnF) without additional CAPEX and OPEX.
• The architecture provides a direct interface between the UE and the AF where a customized application-specific interface can be built, including the key management, key lifetime extension, etc.

The Journal of ICT Standardization has a paper on Authentication Mechanisms in the 5G System. It details AKMA and much more. It's a great place to start for anyone new looking to understand different 5G Authentication Mechanisms. 

Related Posts: 

• The 3G4G Blog: 3GPP Release 17 Description and Summary of Work Items
• The 3G4G Blog: Lawful Intelligence and Interception in 5G World with Data and OTT Apps
• The 3G4G Blog: 5G and Cyber Security
• The 3G4G Blog: Realizing Zero Trust Architecture for 5G Networks
• The 3G4G Blog: AT&T Cybersecurity Experts Provide 5G Security Overview
• The 3G4G Blog: Everything you need to know about 5G Security
• The 3G4G Blog: Introduction to 3GPP Security in Mobile Cellular Networks
• The 3G4G Blog: Initiative to Remove Non-inclusive terms from 3GPP Specifications
• The 3G4G Blog: 3GPP 5G Non Terrestrial Networks (NTN) Standardization Update
• The 3G4G Blog: 3GPP Explains TSG CT Work on UAS Connectivity, Identification and Tracking 

Managing 5G Signalling Storms with Service Communication Proxy (SCP)

When we made our 5G Service Based Architecture (SBA) tutorial some four years back, it was based on Release-15 of the 3GPP standards. All Network Functions (NFs) simply sent discovery requests to the Network Repository Function (NRF). While this works great for trials and small scale deployments it can also lead to issues as can be seen in the slide above.

In 3GPP Release-16 the Service Communication Proxy (SCP) has now been introduced to allow the Control Plane network to handle and prioritize massive numbers of requests in real time. The SCP becomes the control point that mediates all Signalling and Control Plane messages in the network core.

SCP routing directs the flow of millions of simultaneous 5G function requests and responses for network slicing, microservice instantiation or edge compute access. It also plays a critical role in optimizing floods of discovery requests to the NRF and in overall Control Plane load balancing, traffic prioritization and message management.

A detailed whitepaper on '5G Signaling and Control Plane Traffic Depends on Service Communications Proxy (SCP)' by Strategy Analytics is available on Huawei's website here. This report was a follow on from the 'Signaling — The Critical Nerve Center of 5G Networks' webinar here.

Related Posts:

• 3G4G: 5G Service Based Architecture (SBA)
• The 3G4G Blog: Interfacing HSS and UDM in 5GS with UDICOM (a.k.a NU1 / Nhss)
• The 3G4G Blog: 5G Roaming with SEPP (Security Edge Protection Proxy)
• The 3G4G Blog: Everything you need to know about 5G Security
• 3G4G: 3GPP 5G Specifications

AI/ML Enhancements in 5G-Advanced for Intelligent Network Automation

Artificial Intelligence (AI) and Machine Learning (ML) has been touted to automate the network and simplify the identification and debug of issues that will arise with increasing network complexity. For this reason 3GPP has many different features that are already present in Release-17 but are expected to evolve further in Release-18. 

I have already covered some of this topics in earlier posts. Ericsson's recent whitepaper '5G Advanced: Evolution towards 6G' also has a good summary on this topic. Here is an extract from that:

Intelligent network automation

With increasing complexity in network design, for example, many different deployment and usage options, conventional approaches will not be able to provide swift solutions in many cases. It is well understood that manually reconfiguring cellular communications systems could be inefficient and costly.

Artificial intelligence (AI) and machine learning (ML) have the capability to solve complex and unstructured network problems by using a large amount of data collected from wireless networks. Thus, there has been a lot of attention lately on utilizing AI/ML-based solutions to improve network performance and hence providing avenues for inserting intelligence in network operations.

AI model design, optimization, and life-cycle management rely heavily on data. A wireless network can collect a large amount of data as part of its normal operations. This provides a good base for designing intelligent network solutions. 5G Advanced addresses how to optimize the standardized interfaces for data collection while leaving the automation functionality, for example, training and inference up to the proprietary implementation to support full flexibility in the automation of the network.

AI/ML for RAN enhancements

Three use cases have been identified in the Release 17 study item related to RAN performance enhancement by using AI/ML techniques. Selected use cases from the Release 17 technical report will be taken into the normative phase in the next releases. The selected use cases are: 1) network energy saving; 2) load balancing; and 3) mobility optimization.

The selected use cases can be supported by enhancements to current NR interfaces, targeting performance improvements using AI/ML functionality in the RAN while maintaining the 5G NR architecture. One of the goals is to ensure vendor incentives in terms of innovation and competitiveness by keeping the AI model implementation specific. As shown in Fig.2 (on the top) an intent-based management approach can be adopted for use cases involving RAN-OAM interactions. The intent will be received by the RAN. The RAN will need to understand the intent and trigger certain functionalities as a result.

Ericsson White Paper - 5G Advanced: Evolution towards 6G - https://t.co/9ZKnC8PDxX#Free5Gtraining #Ericsson #5G #B5G #5GAdvanced #6G #5GNR #5GC #Timeline #XR #RedCap #NetworkAutomation #EnergySavings #DeterministicNetworking #IoT pic.twitter.com/eeI4SKvIRC

— Free 5G Training (@5Gtraining) July 21, 2022

AI/ML for physical layer enhancements

It is generally expected that AI/ML functionality can be used to improve the radio performance and/or reduced the complexity/overhead of the radio interface. 3GPP TSG RAN has selected three use cases to study the potential air interface performance improvements through AI/ML techniques, such as beam management, channel state information feedback enhancement, and positioning accuracy enhancements for different scenarios. The AI/ML-based methods may provide benefits compared to traditional methods in the radio interface. The challenge will be to define a unified AI/ML framework for the air interface by adequate AI/ML model characterization using various levels of collaboration between gNB and UE.

AI/ML in 5G core

5G Advanced will provide further enhancements of the architecture for analytics and on ML model life-cycle management, for example, to improve correctness of the models. The advancements in the architecture for analytics and data collection serve as a good foundation for AI/ML-based use cases within the different network functions (NFs). Additional use cases will be studied where NFs make use of analytics with the target to support in their decision making, for example, network data analytics functions (NWDAF)- assisted generation of UE policy for network slicing.

If you are interested in studying this topic further, check out 3GPP TR 37.817: Study on enhancement for data collection for NR and ENDC. Download the latest version from here.

Related Posts: 

• The 3G4G Blog: What Is the Role of AI and ML in the Open RAN and 5G Future?
• The 3G4G Blog: 3GPP Release-18 Work Moves Into Focus as Release-17 Reaches Maturity
• The 3G4G Blog: NWDAF in 3GPP Release-16 and Release-17
• The 3G4G Blog: 5G-Advanced Flagship Features
• The 3G4G Blog: 3GPP's 5G-Advanced Technology Evolution from a Network Perspective Whitepaper
• Free 6G Training: Qualcomm Pushing the boundaries of AI research 

GSMAi Webinar: Is the Industry Moving Fast Enough on Standalone 5G?

I recently participated in a webinar, discussing one of my favourite topics, 5G Standalone (5G SA). If you do not know about 5G SA, you may want to quickly watch my short and simple video on the topic here.

Next week I am participating in a webinar, "Open for Debate: Is the Industry Moving Fast Enough on Standalone 5G?" along with Peter Jarich, Radhika Gupta and Tim Hatt. Hope to see you there: https://t.co/TQ8Aa5LXYP #3G4G5G #5G #5GNetworks #5GTechnology #5GNR #5GStandalone #5GSA pic.twitter.com/Rd7hGvvCNe

— Zahid Ghadialy (@zahidtg) July 15, 2022

Last year I blogged about GSA's 5G Standalone webinar here. That time we were discussing why 5G SA is taking time to deliver, it was sort of a similar story this time. Things are changing though and you will see a lot more of these standalone networks later this year and even early next year. 

The slides of the webinar are available here and the video is embedded below:

Here are some of my thoughts on why 5G SA is taking much longer than most people anticipated:

• 5G SA will force operators to move to 5G core which is a completely new architecture. The transition to this is taking much longer than expected, especially if there are a lot of legacy services that needs to be supported.
• Many operators are moving towards converged core with 4G & 5G support to simply the core. This transition is taking long.
• For taking complete advantage of 5G architecture, cloud native implementation is required. Some operators have already started the transition to cloud native but others are lagging.
• 5G SA speeds will be lower than NSA speeds hence some operators who don't have a lot of mid-band spectrum are delaying their 5G SA rollouts.
• Many operators have managed to reduce their latency as they start to move to edge datacentres, hence the urgency for 5G standalone has reduced.
• Most operators do not see any new revenue opportunities because of 5G SA, hence they want to be completely ready before rolling out 5G SA
• Finally, you may hear a lot about not enough devices supporting 5G SA but that's not the device manufacturers views.  See this tweet from GSA 👇

#Supporting5Gstandalone

With 5G SA networks now being launched, GSA is already aware of 842 announced devices with claimed support for 5G SA, up 202% from 278 at the end of 2020.

Full report on: https://t.co/8f1fw4R2fI#5G | #SA | #Devices | #GSA pic.twitter.com/7LEoyasplm

— GSA (@gsacom) July 11, 2022

Do you agree with my reasoning? If not, please let me know in the comments.

Related Posts: 

• The 3G4G Blog: The Status of 5G Standalone (5G SA) Networks - March 2021
• The 3G4G Blog: What will 5G Standalone deliver?
• The 3G4G Blog: The Politics of Standalone vs Non-Standalone 5G & 4G Speeds
• The 3G4G Blog: 5G Reality Check - Data Rates
• Operator Watch Blog: Germany gets Two 5G Standalone Networks
• The 3G4G Blog: Minimum Bandwidth Requirement for 5G Non-Standalone (NSA) Deployment
• The 3G4G Blog: 5G Dual Connectivity, Webinar and Architecture Overview
• The 3G4G Blog: What about 5G Network Architecture Option 4 (a.k.a. NE-DC) ?
• Free 5G Training: 5G Use Cases
• Free 5G Training: 5G Adverts
• 3G4G: 5G for Absolute Beginners 

5G Reality Check - Data Rates

One of the common questions that we encounter is why are 5G speeds so low as we were promised 5G downlink speeds of 20 Gbps. Most people do not understand how the 5G speeds are calculated and what do they depend on. In many cases, the network won’t be capable of delivering higher speeds due to some or the other limitation. 

In a new presentation, I try to explain the theoretical speeds and compare them with real world 5G data rates and even try to map it to why these speeds are what they are. Hopefully people won't mind me adding some humour as I go along.

Video and Slides embedded below

Opinion – 5G Reality Check: Speeds from 3G4G

Embedded below is the Twitter thread on Speedtests 😂

Speed Tests are 5G killer app 😉, @HarriHolma provides details in replies: Elisa 100 MHz 5G (8T8R radio) on 3.5 GHz with LTE dual connectivity (EN-DC). LTE phone gives 200-250 Mbps in the same spot. The configuration uses L800+L1800+L2100 #5GKillerApp https://t.co/5ZnS2UeFkL

— 3G4G (@3g4gUK) November 18, 2019

Related Posts: 

• The 3G4G Blog: IMT-2020 (5G) Requirements
• The 3G4G Blog: Would 5G NSA undergo Sunset? When?
• The 3G4G Blog: The Politics of Standalone vs Non-Standalone 5G & 4G Speeds
• The 3G4G Blog: 5G SpeedTests and Theoretical Max Speeds Calculations
• The 3G4G Blog: Theoretical Throughput Calculation of FDD 5G New Radio (NR)
• The 3G4G Blog: The path from 4.5G to 5G
• The 3G4G Blog: Throughput Comparison for different wireless technologies
• Operator Watch Blog: EE Combines More 4G and 5G Spectrum for Even Higher Data Rates
• Operator Watch Blog: USA has an interesting mix of different types of 5G
• Operator Watch Blog: Is Saudi Arabia Winning the 5G Race?
• Operator Watch Blog: LG Uplus Tests 5G in 28GHz band using 800MHz Bandwidth. Sees AR as 5G Killer App 

Lawful Intelligence and Interception in 5G World with Data and OTT Apps

Not long ago we looked at the 'Impact of 5G on Lawful Interception and Law Enforcement' by SS8. David Anstiss, Senior Solutions Architect at SS8 Networks gave another interesting talk on Evolving Location and Encryption Needs of LEAs in a 5G world at Telecoms Europe Telco to Techco virtual event in March.

In this talk, David provided an insight in​to how 5G is impacting lawful interception and the challenges Law Enforcement Agencies face as they work with Communication Service Providers to gather intelligence and safeguard society. While there is an overlap with the previous talk, in this video David looked at a real world example with WhatsApp. The talk also covered:

• Real-world problems with 5GC encryption
• 5G location capabilities and the impact on law enforcement investigations
• Optimal solutions for both CSPs and LEAs

The video of the talk is embedded below:

Related Posts:

• The 3G4G Blog: Impact of 5G on Lawful Interception and Law Enforcement
• The 3G4G Blog: Lawful Intercept in 5G Networks
• The 3G4G Blog: Everything you need to know about 5G Security
• The 3G4G Blog: Key Technology Aspects of 5G Security by Rohde & Schwarz
• The 3G4G Blog: 5G Roaming with SEPP (Security Edge Protection Proxy)
• The 3G4G Blog: Exploiting Possible 5G Vulnerabilities
• The 3G4G Blog: Presentations from ETSI Security Week 2019 (#ETSISecurityWeek)
• The 3G4G Blog: VoLTE Hacking
• The 3G4G Blog: Evolution of Security from 4G to 5G 

IP Multimedia Subsystem (IMS) Support for Service Based Architecture (SBA)

I looked at IMS briefly in my LTE voice tutorial here. The Nokia Lectures covered IMS in-depth in part 5 of the video. I recently came across a short overview of IMS for SBA. You can see our old tutorial on Service Based Architecture (SBA) for 5G Core (5GC) here.

I came across this short video from Mpirical that nicely explains the IMS support for SBA. It's embedded below. The related posts at the bottom may also be worth checking out.

Related Posts:

• The 3G4G Blog: A quick starter on 4G voice (for beginners)
• The 3G4G Blog: Nokia Lectures in Collaboration with Bangalore University
• The 3G4G Blog - Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)
• The 3G4G Blog: A look at 5G Applications, Application Functions & Application Servers
• The 3G4G Blog: EPS Fallback in 5G Standalone Deployments
• The 3G4G Blog: Voice over New Radio (VoNR) Establishment and Release between NG RAN and 5G Core
• The 3G4G Blog: Two Types of SMS in 5G
• The 3G4G Blog: 5G User Plane Redundancy
• The 3G4G Blog: Network Slicing using User Equipment Route Selection Policy (URSP) 

Bug hunting in 5G Networks and Devices

Pentests or Penetration testing is ethical hacking that is an authorized simulated cyberattack on a computer system, performed to evaluate the security of the system. They are performed to identify weaknesses or vulnerabilities, including the potential for unauthorized parties to gain access to the system's features and data, as well as strengths, enabling a full risk assessment to be completed.

Sébastien Dudek, Founder and Security Engineer at PentHertz did a presentation at No Hat conference 2021. The outline of his talk says:

Expected to be released in 2021, we only see the early stage of 5G-NR connectivity in rare places around the world and we cannot talk yet about "real 5G" as current installations are put on the Non-Standalone mode (NSA) using 4G infrastructures. But in the meantime, it is important to get prepared for this upcoming technology and ways we can practically simulate real-world attacks in the future, with Standalone (SA) mode-capable devices and networks. In this presentation, we will see how to conduct practical security assignments on future 5G SA devices and networks, and how to investigate the protocol stack. To begin the presentation, we briefly present the differences with 2G-5G in terms of security applied to security assessment contexts, i.e. the limit we are left with, and how to circumvent them. Then we see how a 5G-NR security testbed looks like, and discuss what type of bugs are interesting to spot. Third, we make more sense about some attacks on devices by showing attacks that could be performed on the core side from the outside. Finally, we briefly introduce how we could move forward by looking at the 5G protocol stack and the state of the current mean.

Slides are available here and the video is embedded below:

A post on their website also looks at penetration of standalone 5G core. The post contains a video as well which can also be directly accessed here.

A new white paper from 5G Americas provides nearly annual updates around the topic of security in wireless cellular networks. The current edition addresses emerging challenges and opportunities, making recommendations for securing 5G networks in the context of the evolution to cloud-based and distributed networks. 

New whitepaper from 5G Americas, 'Security for 5G' provides a good overview of security in 3GPP Rel-15 & 16 - https://t.co/z0SxZUTWRK#Free5Gtraining #5GAmericas #5G #5GTechnology #5GSecurity #5GCore #SBA #Security #OpenRAN #SuuplyChain #Transportation #ZTN #APIs pic.twitter.com/fnWCIArTFv

— Free 5G Training (@5Gtraining) December 13, 2021

Additionally, the white paper provides insight into securing 5G in private, public, and hybrid cloud deployment models. Topics such as orchestration, automation, cloud-native security, and application programming interface (API) security are addressed. The transition from perimeter-based security to a zero-trust architecture to protect assets and data from external and internal threats is also discussed.

Related Posts: 

• 3G4G: 5G Security Overview by Mpirical
• The 3G4G Blog: Everything you need to know about 5G Security
• The 3G4G Blog: Impact of 5G on Lawful Interception and Law Enforcement
• The 3G4G Blog: Key Technology Aspects of 5G Security by Rohde & Schwarz
• The 3G4G Blog: 5G Roaming with SEPP (Security Edge Protection Proxy)
• 3G4G: Security in 2G, 3G, 4G & 5G Mobile Networks
• Free 6G Training: 6G Security Considerations 

What will 5G Standalone deliver?

Surely you have heard me talk about the benefits of 5G Standalone and why is it needed. At Telecoms Europe 5G 2021, Dr. Kim K Larsen, CTIO, T-Mobile Netherlands, presented a talk on what exactly will 5G Standalone deliver. The video of his talk and slides are embedded below.

5G Standalone Will Deliver! - But What? from Dr. Kim (Kyllesbech Larsen)

If mobile economics is an area of interest, you may want to check out his old blog posts which are quite detailed. Here.

Related Posts:

• The 3G4G Blog: When can we Stop the 5G NSA Experiment?
• The 3G4G Blog: Will Wi-Fi Help 3GPP Bring Reliable Connectivity Indoors?
• The 3G4G Blog: 5G Network Architecture Options 
• The 3G4G Blog: The Politics of Standalone vs Non-Standalone 5G & 4G Speeds
• The 3G4G Blog - Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)
• The 3G4G Blog: When does your 5G NSA Device Show 5G Icon?
• The 3G4G Blog: Would 5G NSA undergo Sunset? When? 

Will Wi-Fi Help 3GPP Bring Reliable Connectivity Indoors?

I have argued a few times now that it would make much more sense to be able to make access and core independent of each other. 3GPP 5G Standards already have a feature available from Release-16 onwards that enables this with 5G Core, Standalone networks.

We use our smart devices currently for voice and data communications. When we are indoor, many times the data goes over Wi-Fi. This is what tempted operators to move to WiFi for voice solution as well. Many operators are now enabling Voice of WiFi in their network to provide reliable voice coverage indoors.

While this works currently without any issues, when operators start offering new native services and applications, like XR over 5G, the current approach won't help. When our devices are connected over Wi-Fi at present, they are unable to take advantage of operator core or services. With access and core independence, this will no longer be an issue.

I gave a short (15 mins) virtual presentation at 5G Techritory this year. I argued not just for WWC but also looked at what 5G features have a potential for revolution. It's embedded below.

Related Posts:

• The 3G4G Blog: 5G and Fixed-Mobile Convergence (FMC)
• The 3G4G Blog: Introduction to 5G ATSSS - Access Traffic Steering, Switching and Splitting
• The 3G4G Blog: Three New Standards to Accelerate 5G Wireless Wireline Convergence (WWC)
• Connectivity Technology Blog: 5G Wireline Access Architecture
• Operator Watch Blog: Telefonica Plans to achieve Fixed Mobile Convergence (FMC)
• Operator Watch Blog: BT's Converged Core to Launch in 2023 

Network Slicing using User Equipment Route Selection Policy (URSP)

Google announced that its latest smartphone OS will include support for 5G network slicing. Last week Telecom TV brought this news to my attention. The article explains:

It's a move designed to leverage its expertise in devices in order to give it the edge over its rival hyperscalers.

It comes in two flavours. The first is for enterprise-owned handsets, and routes all data sent and received by a device over the network slices provided by that company's mobile operator. Android 12 gives operators the ability to manage slices using a new dynamic policy control mechanism called User Equipment Route Selection Policy (URSP). URSP enables devices to automatically switch between different network slices according to which application they are using. For example, someone working for a financial institution might require a highly-secure network slice for sending and receiving sensitive corporate data, but will then require a reliable, high-throughput, low-latency slice so they can participate in a video meeting.

The second flavour is implemented in the work profile. For years, enterprises have had the option of creating work profiles on Android devices – irrespective of whether they are owned by the organisation or the individual – to use as a separate repository for enterprise apps and data. When Android 12 comes out next year, enterprises will be able to route data to and from that repository over a network slice.

Google said it has already carried out network slicing tests with both Ericsson and Nokia using test versions of its recently released Pixel 6 smartphone running on the as-yet-unreleased Android 12 OS.

It's a replacement for enterprise APNs for now. So not earth-shattering, but a start nonetheless.

Perhaps indicates that enterprise privacy/security/policy might be the major use-case for slicing for the foreseeable future?

A type of mobile VPN, in other words.

— Gabriel Brown (@Gabeuk) November 7, 2021

Last week Taiwanese operator Far EasTone (FET) and Ericsson announced they have completed the world’s first proof of concept (PoC) for simultaneously connecting multiple network slices per device running on Android 12 commercial release. The press release said:

The trial, carried out on FET’s 5G standalone (SA) infrastructure built on Ericsson’s radio access network and cloud-native Core network, successfully demonstrated the 5G user equipment slicing policy feature (User Equipment Route Selection Policy, or URSP) on multiple Android devices. This marks a breakthrough in network slicing capabilities on a 5G standalone network and paves the way for further ecosystem development in this important area.

With more 5G networks evolving to standalone architecture around the globe, end-to-end network slicing, which includes Ericsson RAN Slicing to secure Quality of Service (QoS) differentiation, plays a key role in enabling new services for end users, with which multiple virtual 5G networks are created on top of one physical network. The 5G trial, in collaboration with FET, Ericsson and Android, went even further in network slicing capabilities by introducing and demonstrating 5G user equipment (UE) slicing policy (URSP) features that allow devices to simultaneously operate on dynamic policy control and selection between multiple 5G network slices. This enables the steering of applications and services with specific requirements to defined slices without switching devices.

Multiple slices allow devices to have multiple profiles to secure different levels of experience, security, and privacy requirements, based on the needs of the different applications and in correspondence with the user profile.  For instance, a device can have a personal profile with private data from apps or off-work entertainment, and a work profile with enterprises productivity apps. With URSP features, employers can customize the work profile with increased security and enable better use of RAN Slicing with QoS so that enterprise-related apps can work even during network congestion.

Some security-sensitive apps, such as mobile banking, can also benefit from different routing mechanisms of the traffic enabled by URSP. For instance, the banking app would not need to send its traffic to the internet and then to the app server as it does today. Instead, it could go straight to the app server and avoid the routing through internet. With the shortest route by connecting to a defined slice, users could reduce the risk of being attacked by hackers.

In their technical whitepaper on Network Slicing, Samsung explains: 

Along with the concept of network slicing and features in the RAN and Core network, UE Route Selection Policy (URSP) is introduced as a way to manage network slice information for the UE. URSP is a network slice feature enabled by the PCF which informs the network slice status to the UE via the AMF. In 4G network systems, it was near impossible to install new services in the network for a UE. But through the URSP feature, 5G network operators can easily configure new service for a UE. Figure 12 (top of this blog post) shows the difference in network slice selection in 4G and 5G Network. In 5G network, slice selection policy can be configured dynamically through URSP, while slice selection policy is pre-defined and cannot be changed dynamically in 4G network.

URSP contains OSId, AppId, IP descriptors to define the application and Single-Network Slice Selection Assistance Information (S-NSSAI), Data Network Name (DNN), Session and Service Continuity (SSC) mode information for the application and network slice mapping.

The S-NSSAI identifies each network slice service and provides information to properly assign network slice/functions. An S-NSSAI is comprised of:

• A Slice/Service type (SST), which refers to the expected network slice behavior in terms of features and services;
• A Slice Differentiator (SD), which is an optional information that complements the Slice/Service type(s) to differentiate amongst multiple network slices of the same Slice/Service type.

3GPP allows the use of the Slice Differentiator (SD) field that can build customized network slices. The SD field can be used to describe services, customer information and priority.

Here is a short video from Mpirical explaining 5G UE Route Selection.

It it worth reminding here that this feature, like many of the other 5G features, is dependent on 5G Core. We hope that the transition to 5G Standalone Networks happens as soon as possible.

Related Posts:

• The 3G4G Blog: Network Slicing Tutorials and Other Resources
• The 3G4G Blog: 5G Slicing Templates
• The 3G4G Blog: End-to-end Network Slicing in 5G
• The 3G4G Blog: Network Slicing in NG RAN
• The 3G4G Blog: How to Identify Network Slices in NG RAN
• The 3G4G Blog: The Status of 5G Standalone (5G SA) Networks - March 2021
• The 3G4G Blog: The Politics of Standalone vs Non-Standalone 5G & 4G Speeds
• The 3G4G Blog: When can we Stop the 5G NSA Experiment? 

QoS Flow Establishments in 5G Standalone RAN and Core

Today I launched a new video on my YouTube channel that explains how QoS Flows are established in 5G RAN and Core. It also highlights the main differences between 4G E-RAB handling and 5G QoS Flows.

Related Posts: 

• The 3G4G Blog: Anomaly Detection and other AI Algorithms in RAN Optimization
• The 3G4G Blog: How to Identify Network Slices in NG RAN
• The 3G4G Blog: Network Slicing in NG RAN
• The 3G4G Blog: Network Slicing Tutorials and Other Resources
• The 3G4G Blog: Artificial Intelligence (AI) / Machine Learning (ML) in 5G Challenge by ITU
• The 3G4G Blog: Conditional Handover (Rel. 16) Explained
• The 3G4G Blog: UE Radio Capability Signaling Optimization (RACS) in Rel. 16 

When can we Stop the 5G NSA Experiment?

Cross posting from LinkedIn, please post any comments there!

One of the advantages of having been in the industry for a very long time is one knows (and in my case, remembers) the hacks of each generation of mobile technology.

In case of UMTS (3G), the initial version had very poor data rates. Even though 3G was designed to bring data to the masses, there were hardly any applications that could take advantage of the mobile data connectivity. In addition, you could hardly get over 128 kbps (yes, kilo bits per second, not mega bits).

Most people think that the data part was added later on, as HSDPA, HSUPA (collectively HSPA) and HSPA+ from 3GPP Release-5 onwards. This is just one side of the story. The initial version of 3G had Downlink Shared Channel (DSCH) and Uplink Common Packet Channel (CPCH). As nearly all the patents were held by one very small company, none of the big vendors (both in network side as well and device side) implemented it (cartel?) and those channels eventually got removed from the standards.

Politics aside, until the arrival of HSPA, people couldn’t take advantage of mobile broadband.

LTE had already started being standardised while HSPA was being rolled out. LTE promised much higher data rates and reduction in the device power consumption, and it delivered! But… 

Have you heard this industry joke? When the standards engineers were designing 3G, 2G voice and SMS was generating most of income for the operators. Naturally they focussed on Voice and SMS and forgot to design data properly. When it came to design LTE, they focussed so much on data, they forgot to design the voice part.

Not My Job

Well, to be honest, 4G was always planned to be a packet switched (PS) only network, with a flatter and simplified architecture and protocols. With CS domain gone, the RRC and NAS protocols could be simplified. From a RAN engineer point of view, the voice calls would be voice over IP (VoIP) but the people who design the network telephony part didn’t get the memo.

The first set of LTE standards in Release-8 had to rely on this hack called CS Fallback. When nobody was taking ownership of the issue on hand, GSMA stepped in and created Voice over LTE (VoLTE) standards. It was based on the IMS standards that were bandied about for a long time but never got deployed fully. The standards was also complex and even after 8 years of it being standardised, it has still not been deployed everywhere.

5G for Everyone

I have been closely following the developments in 5G for over 6 years now. If you saw and heard the things I did, you would have believed that 5G is a panacea for all the world’s ills. In fact, in reality, it is just another generation of mobile network standards, astutely referred to as 5G JAG (Just Another Generation) by the outspoken industry analyst, Dean Bubley.

In the race to launch 5G by hook or by crook, the Non-Standalone (NSA) version of 5G, option 3 (technical name EN-DC) was launched. It gives the operators the ability to show 5G icon on you smartphones easily while not having to worry too much about delivering all the promises. If an operator has spare or a lot of spectrum, they can then use (some of) it to start transmitting on 5G New Radio (NR). If they don’t have much spectrum then they will have to do some kind of Dynamic Spectrum Sharing (DSS) to show the 5G icon. The problem with DSS is that while it would provide some kind of 5G to everyone capable of receiving it, it spoils the experience of the 4G users who are satisfied or happy with their LTE network.

5G Stands Alone

While all this had been going on, the operators have started buying new 5G spectrum, and started preparing and in many cases rolling out the Real Standalone 5G Network. If an operator has sufficient spectrum and the right kind of spectrum, they can now start to deliver on some of the actual 5G promises. 

I am aware of some of the operators who are already thinking about switching off their Non-Standalone EN-DC networks within the next couple of years. The initial 5G smartphones did not support the Standalone version of 5G networks so the operators will give them enough time to switch over to a newer device capable of standalone network.

So what would happen to a 5G device only supporting NSA 5G, after the NSA network is switched off?

Nothing really. It would still be able to do 4G (and 2G, 3G) which is generally good enough. They would stop seeing the 5G icon and in some cases, won’t benefit with the extra speeds boost.

Switching off 5G NSA will benefit the operator with the simplification of the network, not just from deployment point of view but also from optimization as there is no need for 4G-5G dual connectivity and for the 5G cell to be planned based on the 4G cell.

Industry’s View

5G Training ran a poll on LinkedIn to ask people involved in the 5G industry if they were happy with 5G NSA or would rather go with Standalone 5G, 6G or just satisfied with 4G. Surprisingly most people in the 5G industry said they were waiting for Standalone 5G. This was followed by “Looking forward to 6G!”. “Happy with existing 5G” got the least number of votes. 

This poll is by no measure reliable but it should force the operators, vendors and everyone else to ponder if it makes sense to move to SA sooner rather than later and to switch off NSA as soon as possible.

Non-Standalone Part 2

When the first set of 5G standards were being defined, it was felt that there should be a path to transition from 4G to 5G in the future. While the initial Option 3 (EN-DC) relied on 4G Core or EPC, these future NSA options can rely on 5G core.

Sometimes, in their zeal and enthusiasm, engineers define things that would make everyone’s lives difficult. These options are very much like that. While some operators have asked for Option 4, most people realise that it doesn’t make sense, at least right now to be creating more fragmentation in 5G deployment.

Hopefully rationality will prevail and any major architecture changes we do with 5G going forward will only be done after lots of analysing and thinking about the long term consequences. 

Please post any comments on LinkedIn as comments have been disabled on this post.

3GPP Standards on Edge Computing

A sub-set of 3GPP Market Representation Partners hosted a 2-part webinar series in April 2021 looking at edge computing for industry verticals and on-going standardisation work in 3GPP. The first part write-up is available here. The webinar was attended by a mix of organisations from both verticals and the telecommunication industry, helping to share a common understanding on edge computing. 

The webinar brought together top experts at the 3GPP plenary level, SA2 (Architecture) and SA6 (application enablement and critical communication applications) for a deep-dive into how 5G and related standards can help harmonise and enable technologies like edge computing and artificial intelligence to work together much more efficiently. 

The webinar was co-chaired by Georg Mayer, 3GPP SA Chairman and Stephanie Parker, Trust-IT and Vice-chair of the 5G-IA Pre-Standardisation WG with the John Favaro, Trust-IT and member of the 5G PPP Automotive Working Group. 

The webinar was attended by a mix of organisations from both verticals and the telecommunication industry, helping to share a common understanding on edge computing.

This video embedded below is the recording of the webinar on edge computing held on Thursday 22 April 2021 part 2 - 3GPP Standards on Edge Computing as an educational deep dive to help industry verticals gain a better understanding of an evolving landscape. It gives key insights into 3GPP standardisation work on edge computing with an overview of the main activities taking place within SA (System Aspects and Architecture). Presentations and panel discussions zoom in on the network layer with SA2 Architecture and on the application layer for vertical enablement with SA6 Application Enablement and Critical Communication Applications. The panel discussion with SA TSG, SA2 and SA6 chairmen sheds light on the role of artificial intelligence from both the network and application perspectives, underscoring the vital importance of industry verticals in the standardisation process to meet their specific requirements in 3GPP as a truly global initiative.

PDF of presentations as follows:

• 3GPP SA Standardisation Work on Edge Computing by Georg Mayer, SA TSG Chairman
• SA2 Standards Work on Edge Computing by Puneet Jain (Intel), Chairman of 3GPP SA2 - Architecture
• EDGEAPP - Architedture for enabling Edge Applications by Suresh Chitturi (Samsung), Chairman of 3GPP SA6 - Application Enablement and Critical Communication Applications for vertical markets

Global5G has a summary with main takeaways and poll findings here. The following is from there:

Main Takeaways

1. 5G will help technologies like edge computing and artificial intelligence to harmonise and enable them to work together much more efficiently.
2. 3GPP Release 17 is foundational for edge computing but more will come in future releases given its importance in mobile communications and as we gradually move beyond 5G. The webinar was therefore a timely deep-dive into today's landscape. 
3. Artificial Intelligence and edge computing can both serve as building blocks but in different ways: 
• Network layer perspectives: AI can further optimise edge computing applications.
• Application layer persepctives: Edge computing can be a building block for AI, e.g. offloading limited capabilities from the device to the network.
4. Global initiatives like 3GPP can help reduce regional fragmentation, drive convergence and enable network-compliant rollouts that benefit the ecosystem around the world.
5. As a global initiative, 3GPP is well placed to build on its strong relationships and collaborations with ETSI MEC and GSMA. 
6. It is absolutely essential that industry verticals get involved in 3GPP working groups, which is where key activities take place and where their requirements should be channelled. It is also important that verticals understand how their seemingly specific requirements could be relevant to other sectors. Being part of 3GPP is a complex but highly rewarding experience. It does not need to be a life-long commitment.

Poll Findings - Participant Viewpoints

Do you participate in standardization on edge computing?

Interestingly most respondents do not take part in any standardisation initiatives. Hence the webinar series was an opportunity to highlight the many activities taking place and encourage participants to get involved. Those that do take part mostly contribute to 3GPP and other forums (29%) like ETSI (SDO) and industry associations like 5GAA and 5G-ACIA as some of the early movers on edge computing. Beyond 3GPP, a smaller number of respondents (11%) contribute to ETSI and other forums such as 5GAA and GSMA and the same amount (11%) are involved in other forums.

How important do you think coordination on edge computing standardisation is?

Coordination on edge computing standardisation needs to be prioritised with 65% of respondents saying it's vital and another 33% saying it's quite important. Only 1 respondent said it's not needed. An important output via the 5G-IA Pre-Standardisation WG and supported by panellists and organisers (5G-IA, 5GAA, 5G-ACIA and PSCE) would be a user-friendly guide on edge computing standardisation to help stakeholders navigate the landscape. 

Do you see a need for new areas of standardisation for edge computing?

Findings from this poll are particularly interesting as we have a close split between those that think more standardisation work is needed (47%) and those that don't know (43%) with just 10% saying it's not needed. Webinar organisers have come up with two possible explanations. On the one hand, we may be looking at a fragmented landscape that would benefit from more unification, also from an architecture perspective. On the other hand, organisations looking at the landscape may simply be overwhelmed by the dverse activities taking place. They may also have new applications sitting on top of the network but are not sure if they need to be standardised. Practical guidance could go a long way in clarifying this uncertainty. 

Again, a quick guide on edge computing standardisation could be a useful output, highlighting also the good cooperation already taking place as an important step in the right direction. 

You can see Part 1 of this webinar here.

Related Posts: 

• The 3G4G Blog: Edge Computing - Industry Vertical Viewpoints
• The 3G4G Blog: 5G Private and Non-Public Network (NPN)
• Telecoms Infrastructure Blog: AWS for Public and Private 5G Networks
• Telecoms Infrastructure Blog: AWS Edge to Power Private Networks and Industry 4.0
• The 3G4G Blog - Webinar: Where Edge Meets Cloud by Dean Bubley
• The 3G4G Blog: 5G and Industry 4.0
• The 3G4G Blog: What is Industrial IoT (IIoT) and how is it different from IoT?
• The 3G4G Blog: Can Augmented & Mixed Reality be the Killer App 5G needs?
• Telecoms Infrastructure Blog: Edge Computing and the Future of Small Cell Networks
• Free 6G Training - 6G in the sky: On‐demand intelligence at the edge of 3D networks 

5G User Plane Redundancy

We looked at the 5G Enhanced URLLC (eURLLC) earlier. One of the ways to improve reliability is to have redundancy in the user plane. This can use different approaches like: 

• Duplicating N3
• Adding a secondary gNB using Dual connectivity
• Introducing another UPF
• Two anchor UPFs

In fact they are all built on top of each other so you can decide how critical are your user plane redundancy needs. 

I came across this short video from Mpirical embedded below that covers this topic nicely. In case you want to refresh your 5G Core Network architecture, jump to our old tutorial here.

Related Posts:

• The 3G4G Blog: 5G Enhanced URLLC (eURLLC)
• The 3G4G Blog - Ultra Reliability: 5x9s (99.999%) in 3GPP Release-15 vs 6x9s (99.9999%) in 3GPP Release-16 
• The 3G4G Blog - Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)
• 3G4G: 3GPP 5G Specifications
• 3G4G: 5G (IMT-2020) Wireless