Summary of 3GPP Release-14 Work Items

With all focus on 5G (Release-15), looks like Rel-14 has been feeling a bit neglected. There are some important updates though as it lays foundation for other services.

3GPP used to maintain Release Descriptions here for all different releases but have stopped doing that since 2014. For Release-14, a new document "3GPP TR 21.914: Release 14 Description; Summary of Rel-14 Work Items" is now available here.

An executive summary from the document:

Release 14 focusses on the following items:

• Improving the Mission Critical aspects, in particular with the introduction of Video and Data services
• Introducing the Vehicle-to-Everything (V2X) aspects, in particular the Vehicle-to-Vehicle (V2)
• Improving the Cellular Internet of Things (CIoT) aspects, with 2G, 3G and 4G support of Machine-Type of Communications (MTC)
• Improving the radio interface, in particular by enhancing the aspects related to coordination with WLAN and unlicensed spectrum
• A set of uncorrelated improvements, e.g. on Voice over LTE (VoLTE), IMS, Location reporting.

The continuation of this document provides an exhaustive view of all the items specified by 3GPP in Release 14.

I have blogged about the Mission Critical Communications here. 3GPP has also done a webinar on this topic which can be viewed here. I like this slide below that summarizes features in different releases.

Then there are quite a few new features and enhancements for V2X. I have blogged about sidelink and its proposed extensions here.

From the document:

The Work Item on “Architecture enhancements for LTE support of V2X services (V2XARC)”, driven by SA WG2, specifies the V2X architectures, functional entities involved for V2X communication, interfaces, provisioned parameters and procedures in TS 23.285.

Figure above depicts an overall architecture for V2X communication. V2X Control Function is the logical function defined for network related actions required for V2X and performs authorization and provisioning of necessary parameters for V2X communication to the UE via V3 interface.

A UE can send V2X messages over PC5 interface by using network scheduled operation mode (i.e. centralized scheduling) and UE autonomous resources selection mode (i.e. distributed scheduling) when the UE is "served by E-UTRAN" while a UE can send V2X messages over PC5 interface only by using UE autonomous resources selection mode when the UE is "not served by E-UTRAN". 

Both IP based and non-IP based V2X messages over PC5 are supported. For IP based V2X messages over PC5, only IPv6 is used. PPPP (ProSe Per-Packet Priority) reflecting priority and latency for V2X message is applied to schedule the transmission of V2X message over PC5.

A UE can send V2X messages over LTE-Uu interface destined to a locally relevant V2X Application Server, and the V2X Application Server delivers the V2X messages to the UE(s) in a target area using unicast delivery and/or MBMS (Multimedia Broadcast/Multicast Service) delivery.

Both IP based and non-IP based V2X messages are supported for V2X communication over LTE-Uu. In order to transmit non-IP based V2X messages over LTE-Uu, the UE encapsulates the V2X messages in IP packets.

For latency improvements for MBMS, localized MBMS can be considered for localized routing of V2X messages destined to UEs.

For V2X communication over LTE-Uu interface, the V2X messages can be delivered via Non-GBR bearer (i.e. an IP transmission path with no reserved bitrate resources) as well as GBR bearer (i.e. an IP transmission path with reserved (guaranteed) bitrate resources). In order to meet the latency requirement for V2X message delivery, the following standardized QCI (QoS Class Identifier) values defined in TS 23.203 can be used:

• QCI 3 (GBR bearer) and QCI 79 (Non-GBR bearer) can be used for the unicast delivery of V2X messages.
• QCI 75 (GBR bearer) is only used for the delivery of V2X messages over MBMS bearers. 

There are updates to cellular IoT (CIot) which I have blogged about here.

There are some other interesting topic that are enhanced as part of Release14. Here are some of them:

S8 Home Routing Architecture for VoLTE

• Robust Call Setup for VoLTE subscriber in LTE
• Enhancements to Domain Selection between VoLTE and CDMA CS
• MBMS improvements
• eMBMS enhancements for LTE
• IMS related items
• Evolution to and Interworking with eCall in IMS
• Password-based service activation for IMS Multimedia Telephony service
• Multimedia Priority Service Modifications
• Enhancements to Multi-stream Multiparty Conferencing Media Handling
• Enhancement for TV service
• Improved Streaming QoE Reporting in 3GPP (IQoE)
• Quality of Experience (QoE) Measurement Collection for streaming services in UTRAN
• Development of super-wideband and fullband P.835
• Enhancements to User Location Reporting Support
• Enhancing Location Capabilities for Indoor and Outdoor Emergency Communications
• Further Indoor Positioning Enhancements for UTRA and LTE
• Improvements of awareness of user location change
• Terminating Access Domain Selection (T-ADS) supporting WLAN Access
• Enhanced LTE-WLAN Aggregation (LWA)
• Enhanced LTE WLAN Radio Level Integration with IPsec Tunnel (eLWIP)
• Positioning Enhancements for GERAN
• New GPRS algorithms for EASE
• RRC optimization for UMTS
• Multi-Carrier Enhancements for UMTS
• DTX/DRX enhancements in CELL_FACH
• LTE radio improvements
• Enhancements on Full-Dimension (FD) MIMO for LTE
• Downlink Multiuser Superposition Transmission for LTE
• Performance enhancements for high speed scenario in LTE
• Control and User Plane Separation (CUPS) of EPC nodes
• Paging Policy Enhancements and Procedure
• Shared Subscription Data Update
• Service Domain Centralization
• Control of Applications when Third party Servers encounter difficulties
• PS Data Off Services
• Enhancement to Flexible Mobile Service Steering 
• Sponsored data connectivity improvements
• Group based enhancements in the network capability exposure functions
• Improved operator control using new UE configuration parameters
• Charging and OAM stand alone improvements
• Rel-14 Charging
• ...

Further Reading:

• 3GPP Release 14 - Techplayon
• Enhanced Television Services over 3GPP eMBMS
• RAN Evolution of LTE in Release 14
• 3GPP announces RAN work programme for R14
• LTE System Information According to Release 14 (3GPP TS 36.300 V14.3.0 )

SMS is 25 years old today

SMS is 25 years old. The first SMS, "Merry Christmas" was sent on 3rd December 1992 from PC to the Orbitel 901 handset (picture above), which was only able to receive SMS but not send it. Sky news has an interview with Neil Papworth - the man who sent the very first one back in 1992 here.

While SMS use has been declining over some time, thanks to messaging apps on smartphones like WhatsApp, Viber, Facebook messenger, etc., it is still thought to be used for sending 20 billion messages per day.

While I dont have the latest figures, according to analyst Benedict Evans, WhatsApp and WeChat combined are now at over 100bn messages per day.

The global SMS system peaked at maybe 20bn messages a day. WhatsApp and WeChat combined are now at over 100bn

— Benedict Evans (@BenedictEvans) November 12, 2017

According to Daily Mirror, by the end of 2017, researchers expect 32 trillion messages to be sent annually over apps compared to only 7.89 trillion text messages.

You DO understand that everybody in the light blue part can be reached by SMS?
And the green line is all who can be reached by the internet.
FB is far less than green line.
Apps far less than FB.
Whatsapp far less than apps
RT @gassee pic.twitter.com/2ZCZR6ynjI

— Tomi Ahonen (@tomiahonen) November 28, 2017

Tomi Ahonen makes an interesting in the tweet above, all cellular phone users have SMS capability by default while only smartphone users who have downloaded the messaging apps can be reached by a particular messaging app. The reach of SMS will always be more than any competing apps.

That is the reason why GSMA is still betting on RCS, an evolution of SMS to compete with the messaging apps. My old post on RCS will provide some basic info here. A very recent RCS case studies document from GSMA here also provides some good info.

RCS will have a lot of hurdles and challenges to overcome to succeed. There is a small chance it can succeed but this will require change of mindset by operators, especially billing models for it to succeed.

Dean Bubley from Disruptive Analysis is a far bigger skeptic of RCS and has written various posts on why it will fail. One such post that makes interesting reading is here.

Anyway, love it or hate it, SMS is here to stay!

See Also:

• Lost in Time – The Fathers of SMS

Macrocells, Small Cells & Hetnets Tutorial

I blogged about it on the Small Cells blog but cross posting here, just in case you missed it. I am making some videos sharing basic information about mobile technology. Its on YouTube here.

Recently I made some videos looking at all kinds of cellular infrastructure; playlist is embedded below. If you need slides, get it from 3G4G slideshare channel here.

5G and CBRS Hype?

The dissenting voices on 5G and CBRS are getting louder. While there are many analysts & operators who have been cautioning against 5G, its still moving ahead with a rapid pace. In the recent Huawei Mobile Broadband forum for example, BT's boss admitted that making case for 5G is hard. Bruno Jacobfeuerborn, CTO of Deutsche Telekom on the other hand is sitting on the fence. Dean Bubley's LinkedIn post is interesting too.

Vodafone CTO asked yesterday: "Will 5G be like 2G and 4G, or like 3G?". Now, it's like 3G, designing use cases and apps that nobody knows if they will be successful (e.g. 3G video calling).
2G and 4G were all about letting users/developers create their own. #HWMBBF

— Dimitris Mavrakis (@dmavrakis) November 16, 2017

. @BJacobfeuerborn says the forthcoming glut of sporting events in Asia (three Olympics, winter and summer, in next five years) will give them a 5G headstart. "If you want to do massive infrastructure investment, you need events." #HWMBBF

— Mobile Europe (@mobileeurope) November 16, 2017

Anyway, we have storified most of the tweets from Huawei Mobile Broadband Forum here.

Signals Research Group recently published their Signals Flash report, which is different from the more detailed Signals Ahead reports looking at 5G and CBRS, in addition to other topics. I have embedded the report below (with permission - thanks Mike) but you can download your own copy from here.

The summary from their website will give a good idea of what that is about:

CBRS – Much Ado About Not Very Much.  The FCC is heading in the right direction with how it might regulate the spectrum. However, unless you are a WISP or a private entity looking to deploy a localized BWA service, we don’t see too many reasons to get excited.

Handicapping the 5G Race.  Millimeter wave networks will be geographically challenged, 600 MHz won’t scale or differentiate from LTE, Band 41 may be the most promising, but this isn’t saying much. Can network virtualization make a winner?

It makes no Cents! Contrary to widespread belief,  5G won’t be a new revenue opportunity for operators – at least in the near term. The vertical markets need to get on board while URLLC will lag eMBB and prove far more difficult to deploy.

This Fierce Wireless article summarises the issues with CBRS well.

“While (some) issues are being addressed, the FCC can’t solve how to carve up 150 MHz of spectrum between everyone that wants a piece of the pie, while also ensuring that everyone gets a sufficient amount of spectrum,” the market research firm said in a report. “The 150 MHz is already carved up into 7- MHz for PAL (Priority Access License) and 80 MHz for GAA (General Authorized Access). The pecking order for the spectrum is incumbents, followed by PAL, and then by GAA…. 40 MHz sounds like a lot of spectrum, but when it comes to 5G and eMBB, it is only somewhat interesting, in our opinion. Further, if there are multiple bidders going after the PAL licenses then even achieving 40 MHz could be challenging.”

Signals said that device compatibility will also be a significant speed bump for those looking to leverage CBRS. Manufacturers won’t invest heavily to build CBRS-compatible phones until operators deploy infrastructure “in a meaningful way,” but those operators will need handsets that support the spectrum for those network investments to pay dividends. So while CBRS should prove valuable for network operators, it may not hold as much value for those who don’t own wireless infrastructure.

“The device ecosystem will develop but it is likely the initial CBRS deployments will target the more mundane applications, like fixed wireless access and industrial IoT applications,” the firm said. “We believe infrastructure and devices will be able to span the entire range of frequencies—CBRS and C-Band—and the total amount of available spectrum, combined with the global interest in the C-Band for 5G services, will make CBRS more interesting and value to operators. Operators will just have to act now, and then wait patiently for everything to fall into place.”

While many parts of the world are focusing on using frequencies around and above 3.5GHz for 5G, USA would be the only country using it for 4G. I suspect that many popular devices may not support CBRS but could be good for Fixed Wireless Access (FWA). It remains to be seen if economy of scale would be achieved.

Signals Flash Nov 2017: 5G in Americas | Signals Research Group from 3G4G

5G NR Radio Protocols and Tight Inter-working with LTE

Osman Yilmaz, Team Leader & Senior Researcher at Ericsson Research in Finland gave a good summary of 5G NR at URLLC 2017 Conference (see summary here). His presentation is embedded below:

5G NR radio protocols to support URLLC from 3G4G

Osman, along with Oumer Teyeb, Senior Researcher at Ericsson Research & member of the Ericsson 5G standardization delegation has also published a blog post LTE-NR tight-interworking on Ericsson Research blog.

The post talks about how how signalling and data will work in LTE & New Radio (NR) dual connected devices. In control plane it looks at RRC signalling applicable for this DC devices whereas in user plane it looks at direct and split DRB options.

Further details here.

A practical use of MOCN in ESN

Just came across this slide from recent DAS & Small Cells Congress where EE talked about their ESN network development. Found this particular example interesting as they talk about how the commercial user and ESN user would use the same RAN but a different core.

This ties nicely with a recent tutorial that I did on Mobile Network Sharing options. If you would like to learn more, see here.

Related Post (added 23 March 2019)

• Update on UK's Emergency Services Network (ESN) from BAPCO 2019

Ultra Reliable Low Latency Communications (URLLC) 2017 Conference summary

Picture Source: Martin Geddes

It was a pleasure to attend this conference this week. Not only was the topic of interest but I am always impressed by how well EIE organizes their events. Instead of writing my own summary, here is a story created from tweets, 'The Mobile Network' live blog and a summary write-up from Martin Geddes. I have my takeaways below.

URLLC 2017 (#URLLC2017) conference summary from 3G4G

My takeaway from the conference is that:

• URLLC is going to be challenging but its achievable.
• Ultra-reliable (UR) may have different use cases then low latency communication (LLC). Lumping them together in URLLC is not helpful.
• Extremely low latency may not be achievable in every scenario. In some cases it would make more sense to continue with existing or proprietary solutions.
• URLLC may not happen when 5G is rolled out initially but will happen not long after that. 
• There are many verticals who may be able to take advantage of both the higher data rates that would come as part of eMBB and the low latency and high reliability as part of URLLC. 
• The operators would have to foot the bill for upgrading the networks as there is a relucatnce from the verticals to invest in something they cant see or play with
• There are verticals who invest heavily in alternative solutions that 5G may be able to solve. Some operators believe that this will bring new revenue to the mobile operators
• Slicing has a lot of open questions including Security and SLAs - nobody has a clear cut answer at the moment
• The industry is in a learning phase, figuring things out as they go along. There should be much more clarity next year.
• #URLLC2018 is on 13 & 14 Nov. 2018 in London. Plenty of time to find all the answers 😉

Further reading:

• Conference report: Ultra Reliable Low Latency Communications 2017 - Martin Geddes
• URLLC 2017 LiveBlog: The Mobile Network
• Couple of quick interviews from URLLC 2017 Conference
• 5G Research Presentation on URLLC - Mehdi Bennis

Couple of quick interviews from URLLC 2017 Conference

I tried the Facebook Live feature yesterday at the URLLC 2017 conference and recorded a couple of quick interviews with Martin Geddes and Prof. Andy Sutton. Hope you find them useful.

           

Further Reading:

• Ultra Reliable Low Latency Communications (URLLC) 2017 Conference summary

5G Research Presentation on URLLC

Dr.Mehdi Bennis from Centre for Wireless Communications, University of Oulu, Finland recently did a keynote at The International Conference on Wireless Networks and Mobile Communications (WINCOM'17), November 01-04, 2017, Rabat, Morocco. He has shared his presentation with us. Its embedded below and available to download from Slideshare.

Picture Source: Ericsson

For those who may not be aware, there are 3 main use cases defined for 5G. As shown in the picture above, they are enhanced Mobile BroadBand (eMBB), Ultra-Reliable Low Latency Communications (URLLC) and massive Machine Type Communications (mMTC). You can read the requirements here.

Building the foundations of Ultra-RELIABLE and Low-LATENCY Wireless Communication from 3G4G

Further Reading:

• Couple of quick interviews from URLLC 2017 Conference
• Ultra Reliable Low Latency Communications (URLLC) 2017 Conference summary
• 5G on 3G4G Blog

Quick tutorial on Mobile Network Sharing Options

Here is a quick tutorial on mobile network sharing approaches, looking at site/mast sharing, MORAN, MOCN and GWCN. Slides and video embedded below. If for some reason you prefer direct link to video, its here.

Mobile Network Sharing from 3G4G

See also:

• Telecoms Infrastructure Blog: Passive and Active Infrastructure Sharing
• Telecoms Infrastructure Blog: Small Cells Network Sharing
• The 3G4G Blog: Network Sharing is becoming more relevant with 5G
• The 3G4G Blog: A practical use of MOCN in ESN

RRC states in 5G

Looking back at my old post about UMTS & LTE (re)selection/handovers, I wonder how many different kinds of handovers and (re)selection options may be needed now.

In another earlier post, I talked about the 5G specifications. This can also be seen in the picture above and may be easy to remember. The 25 series for UMTS mapped the same way to 36 series for LTE. Now the same mapping will be applied to 38 series for 5G. RRC specs would thus be 38.331.

A simple comparison of 5G and LTE RRC states can be seen in the picture above. As can be seen, a new state 'RRC Inactive' has been introduced. The main aim is to maintain the RRC connection while at the same time minimize signalling and power consumption.

Looking at the RRC specs you can see how 5G RRC states will work with 4G RRC states. There are still for further studies (FFS) items. Hopefully we will get more details soon.

3GPP TS 22.261, Service requirements for the 5G system; Stage 1 suggests the following with regards to inter-working with 2G & 3G

5.1.2.2 Legacy service support
The 5G system shall support all EPS capabilities (e.g., from TSs 22.011, 22.101, 22.278, 22.185, 22.071, 22.115, 22.153, 22.173) with the following exceptions:
- CS voice service continuity and/or fallback to GERAN or UTRAN,
- seamless handover between NG-RAN and GERAN,
- seamless handover between NG-RAN and UTRAN, and
- access to a 5G core network via GERAN or UTRAN.

5G Forecasts and 5G Deployed Claim

Source: GSA

5G forecasts have been arriving steadily with many different figures. Here are some numbers:

Date	Predicted by	Number of Connections	Year	Any other comments
23-Aug-16	Strategy Analytics	690 million	2025	"690M Connections and 300M Handset Shipments"
15-Nov-16	Ericsson	500 million	2022	"North America will lead the way in uptake of 5G subscriptions, where a quarter of all mobile subscriptions are forecast to be for 5G in 2022."
30-Nov-16	ABI Research	500 million	2026	"500 Million 5G cmWave and mmWave Subscribers Will Bring $200 Billion in Service Revenue through 2026" - what about non mmWave/cmWave 5G subs?
12-Apr-17	CCS Insight	100 million	2021	"Smartphones sales will rise to 1.90 billion in 2021, when smartphones will account for 92 percent of the total mobile phone market."
26-Apr-17	GSMA	1.1 billion	2025	"5G connections are set to reach 1.1 billion by 2025, accounting for approximately one in eight mobile connections worldwide by this time."
16-May-17	Ovum	389 million	2022	"Ovum now forecasts that there will be 111 million 5G mobile broadband subscriptions at end-2021, up more than fourfold from Ovum’s previous forecast of 25 million 5G subscriptions at end-2021"
14-Aug-17	Juniper Research	1.4 billion	2025	"an increase from just 1 million in 2019, the anticipated first year of commercial launch. This will represent an average annual growth of 232%."
17-Oct-17	GSMA	214 million in Europe	2025	"30 per cent of Europe’s mobile connections will be running on 5G networks by 2025"
23-Oct-17	CCS Insight	2.6 billion	2025	"1 Billion Users of 5G by 2023, with More Than Half in China", "broadly similar path to 4G LTE technology...more than one in every five mobile connections."

If we just look at 2025/2026, the estimates vary from 500 million to 2.6 billion. I guess we will have to wait and see which of these figures comes true.

I wrote a post earlier titled '4G / LTE by stealth'. Here I talked about the operators who still had 3G networks while most people had 4G phones. The day the operator switched on the 4G network, suddenly all these users were considered to be on 4G, even if they didn't have 4G coverage just yet.

I have a few questions about what 5G features are necessary for the initial rollout and when can an operator claim they have 5G? In fact I asked this question on twitter and I got some interesting answers.

Question: How many 5G sites does an operator have to deploy so that they can say they have 5G?

— Zahid Ghadialy (@zahidtg) October 18, 2017

Just having a few 5G NR (new radio) sites enough for an operator to claim that they have deployed 5G? Would all the handsets with 5G compatibility then be considered to be on 5G? What features would be required in the initial rollouts? In case of LTE, operators initially only had Carrier Aggregation deployed, which was enough to claim they supported LTE-A. Would 100MHz bandwidth support be enough as initial 5G feature?

Please let me know what you think.

5G Architecture Options for Deployments?

I have blogged earlier about the multiple 5G Architecture options that are available (see Deutsche Telekom's presentation & 3G4G video). So I have been wondering what options will be deployed in real networks and when.

The 3GPP webinar highlighted that Option-3 would be the initial focus, followed by Option 2.

Last year AT&T had proposed the following 4 approaches as in the picture above. Recall that Option 1 is the current LTE radio connected to EPC.

ZTE favours Deployment option 2 as can be seen in the slide above

Huawei is favoring Option 3, followed by Option 7 or 2 (& 5)

Going back to the original KDDI presentation, they prefer Option 3, followed by Option 7.

If you are an operator, vendor, analyst, researcher, or anyone with an opinion, what options do you prefer?

Evolution of SON in 3GPP

A good list of 3GPP Evolution of SON features. Whitepaper available here. You may also like the earlier post here.

See also: Self-Organizing Networks / Self-Optimizing Networks (SON) - 3G4G Homepage

3GPP Sidelink and its proposed extensions

In an earlier post I discussed briefly about the sidelink: V2V communications are based on D2D communications defined as part of ProSe services in Release 12 and Release 13 of the specification. As part of ProSe services, a new D2D interface (designated as PC5, also known as sidelink at the physical layer) was introduced and now as part of the V2V WI it has been enhanced for vehicular use cases, specifically addressing high speed (up to 250Kph) and high density (thousands of nodes).

Before going further, lets just quickly recap the different V2x abbreviations:

• V2X = Vehicle-to-Everything
• V2V = Vehicle-to-Vehicle
• V2I = Vehicle-to-Infrastructure 
• V2P = Vehicle-to-Pedestrian 
• V2H = Vehicle-to-Home
• eV2X = enhanced Vehicle-to-Everything

I came across this interesting presentation from ITRI that provides lot more details on sidelink and its proposed extension to other topics including eV2X and FeD2D (Further enhanced Device-to-Device).

There are quite a few references in the document that provides more details on sidelink and its operation and extension to other devices like wearables.

There are also details on synchronization and eV2X services.

There is also a very nice D2D overview presentation by Orange that I am embedding below (download from slideshare)

2G / 3G Switch Off: A Tale of Two Worlds

Source: Wikipedia

2G/3G switch off is always a topic of discussion in most conferences. While many companies are putting their eggs in 4G & 5G baskets, 2G & 3G is not going away anytime soon.

Based on my observations and many discussions that I have had over the past few months, I see a pattern emerging.

In most developed nations, 2G will be switched off (or some operators may leave a very thin layer) followed by re-farming of 3G. Operators will switch off 3G at earliest possible opportunity as most users would have moved to 4G. Users that would not have moved to 4G would be forced to move operators or upgrade their devices. This scenario is still probably 6 - 10 years out.

As we all know that 5G will need capacity (and coverage) layer in sub-6GHz, the 3G frequencies will either be re-farmed to 4G or 5G as 2G is already being re-farmed to 4G. Some operators may choose to re-balance the usage with some lower frequencies exchanged to be used for 5G (subject to enough bandwidth being available).


On the other hand, in the developing and less-developed nations, 3G will generally be switched off before 2G. The main reason being that there are still a lot of feature phone users that rely on 2G technologies. Most, if not all, 3G phones support 2G so the existing 3G users will be forced onto 2G. Those who can afford, will upgrade to newer smartphones while those who cant will have to grudgingly use 2G or change operators (not all operators in a country will do this at the same time).

Many operators in the developing countries believe that GSM will be around until 2030. While it may be difficult to predict that far in advance, I am inclined to believe this.

For anyone interested, here is a document listing 2G/3G switch off dates that have been publicly announced by the operators.

2G/3G Switch off Dates from 3G4G

Let me know what you think.

Further reading:

• 2G Network Decommissioning, Ready? - Russell Lundberg, Bangkok Beach Telecom

Smartphone Wi-Fi Analytics for Travel Route Optimisations

Transport for London (TFL), the local government body responsible for transport in London, which also runs the London Underground (known as Tubes) has been using smartphone Wi-Fi data to work out how people travel on the stations.

They did the trial and collected data in 2016 and have also openly talked about it (see this talk for example), they have now published their findings which is available here. One of the interesting findings for example is that 18 different routes taken by customers between King's Cross St Pancras and Waterloo - and many people don't use the shortest route changing Tube lines

Its interesting to think that because many people do not have their Wi-Fi switched on while outside and many others who put their phone in plane more while in the underground (no mobile coverage, in case you are wondering), this data is probably not as detailed as it could have been.

Nevertheless, there is a talk of bringing Mobile connectivity into the underground network. Once its there, the combination of data could be far more valuable.

5G Dual Connectivity, Webinar and Architecture Overview

One of the things that will come as a result of NSA (Non-StandAlone) architecture will be the option for Dual Connectivity (DC). In fact, DC was first introduced in LTE as part of 3GPP Release 12 (see 3G4G Small Cells blog entry here). WWRF (Wireless World Research Forum) has a good whitepaper on this topic here and NTT Docomo also has an excellent article on this here.

A simple way to understand the difference between Carrier Aggregation (CA) and Dual Connectivity (DC) is that in CA different carriers are served by the same backhaul (same eNB), while in DC they are served by different backhauls (different eNB or eNB & gNB).


We have produced a short video showing different 5G architectures, looking mainly at StandAlone (SA) and Non-StandAlone (NSA) architectures, both LTE-Assisted and NR-Assisted. The video is embedded below:

Finally, 3GPP has done a short webinar with the 3GPP RAN Chairman Balazs Bertenyi explaining the outcomes from RAN#77. Its available on BrightTalk here. If you are interested in the slides, they are available here.

Related posts:

• 5G Core Network, System Architecture & Registration Procedure
• 5G: Architecture, QoS, gNB, Specifications - April 2017 Update
• 5G Security Updates - July 2017
• Enhanced 5G Security via IMSI Encryption
• 5G – Beyond the Hype
• Network Sharing is becoming more relevant with 5G

Slides from IEEE 5G Webinar: 5G mmWave Revolution & New Radio

Some of you may find this useful.

A quick starter on 4G voice (for beginners)

I recently did a 4G voice presentation for beginners after realizing that even though so many years have passed after VoLTE was launched, people are still unsure how it works or how its different from CS Fallback.

There are many other posts that discuss these topics in detail on this blog (follow the label) or on 3G4G website. Anyway, here is the video:

The slides are available on 3G4G Slideshare account here. More similar training videos are available here.

NB-IoT based smart bicycle lock

Huawei (see here and here) has partnered with China Telecom and Bike sharing company called Ofo.

ofo developed an IoT smart lock based on NB-IoT technology that lowers power consumption, enables wide coverage, and slashes system resource delays at low cost. NB-IoT lets ofo ensure it has bikes located at key locations when commuter demand is highest. Meanwhile, bikes can be unlocked in less than a second. Both improvements have greatly boosted user satisfaction.

ofo and its partners added key technologies to ofo’s own platform. These included the commercial network provided by China Telecom, and Huawei’s intelligent chip-based NB-IoT solution. When launching its NB-IoT solution earlier this year, ofo founder and CEO Dai Wei said that the cooperation between ofo, Huawei, and China Telecom is a “mutually beneficial joint force of three global leading enterprises.”

At the core is Huawei’s IoT solution, which includes smart chips, networking, and an IoT platform. The solution provides strong coverage in poor-signal areas and a network capacity that’s more than one hundred times stronger than standard terminals. The payment process has dropped from 25 seconds to less than 5, while battery life has been lengthened from 1 or 2 months to more than 2 years, saving costs and reducing the need for frequent maintenance.

ofo’s cooperation with Huawei on NB-IoT smart locks bodes well for improving the industry as whole. Huawei’s technology optimizes lifecycle management for locks, while the sensors on the locks collect information such as equipment status, user data, and operating data. They connect the front- and back-end industrial chains to achieve intelligent business management, enable the bikes to be located in hot spots, facilitate rapid maintenance, and boost marketing and value-added services.

This video gives an idea of how this works:



As per Mobile World Live:

Ofo co-founder Xue Ding said during a presentation the high power efficiency and huge capacity of NB-IoT make the technology ideal to deliver its smart locks, which are really the brains of its operations.

The company offers what is termed station free pushbike hire, meaning bikes can be collected and deposited from any legal parking spot. Users can locate bikes using their smartphone, and unlock it by scanning a barcode.

However, the process can be interrupted by mobile network congestion or if signals are weak – for example in remote areas: “Using NB-IoT, users will not be stuck because of inadequate capacity,” Xue said.
...
Xiang Huangmei, a VP at China Telecom’s Beijing branch, said the low power consumption of the NB-IoT chip in the lock means the battery will last eight years to ten years, so it will never need to be replaced during the standard lifecycle of an Ofo bike.

The NB-IoT network, deployed on the 800MHz band, offers good indoor and outdoor coverage, the VP said citing car parks as an example. One base station can support 100,000 devices over an area of 2.5 square-km.

Finally, to know which operator is supporting which IoT technology, see the IoT tracker here.

Smartphone Batteries Round-up: Technology, Charging & Recycling

Back in 2013, I spoke about Smart Batteries. Still waiting for someone to deliver on that. In the meantime I noticed that you can use an Android phone to charge another phone, via cable though. See the pic below:

You are probably all aware of the Samsung Galaxy Note 7 catching fires. In case you are interested in knowing the reasons, Guardian has a good summary here. You can also see the pic below that summarises the issue.

Lithium-ion batteries have always been criticized for its abilities to catch fire (see here and here) but researchers have been working on ways to reduce the risk of fire. There are some promising developments.

The electrochemical masterminds at Stanford University have created a lithium-ion battery with built-in flame suppression. When the battery reaches a critical temperature (160 degrees Celsius in this case), an integrated flame retardant is released, extinguishing any flames within 0.4 seconds. Importantly, the addition of an integrated flame retardant doesn't reduce the performance of the battery.

Researchers at the University of Maryland and the US Army Research Laboratory have developed a safe lithium-ion battery that uses a water-salt solution as its electrolyte. Lithium-ion batteries used in smartphones and other devices are typically non-aqueous, as they can reach higher energy levels. Aqueous lithium-ion batteries are safer as the water-based electrolytes are inflammable compared to the highly flammable organic solvents used in their non-aqueous counterparts. The scientists have created a special gel, which keeps water from reacting with graphite or lithium metal and setting off a dangerous chain reaction.

Bloomberg has a good report as to why we’re going to need more Lithium.

Starting about two years ago, fears of a lithium shortage almost tripled prices for the metal, to more than $20,000 a ton, in just 10 months. The cause was a spike in the market for electric vehicles, which were suddenly competing with laptops and smartphones for lithium ion batteries. Demand for the metal won’t slacken anytime soon—on the contrary, electric car production is expected to increase more than thirtyfold by 2030, according to Bloomberg New Energy Finance.

Even if the price of lithium soars 300 percent, battery pack costs would rise only by about 2 percent.

University of Washington researchers recently demonstrated the world's first battery-free cellphone, created with funding from the U.S. National Science Foundation (NSF) and a Google Faculty Research Award for mobile research.

The battery-free technology harvests energy from the signal received from the cellular base station (for reception) and the voice of the user (for transmission) using a technique called backscattering. Backscattering for battery-free operation is best known for its use in radio frequency identification (RFID) tags, typically utilized for applications such as locating products in a warehouse and keeping track of high-value equipment. An RFID base station (called a reader) "pings" the tag with an RF pulse, which allows the tag to harvest microwatts of energy from it—enough to return a backscattered RF signal modulated with the identity of the item.



Unfortunately, harvesting generates very little energy; so little, that you really need a new standard. For instance, Wi-Fi signals transmit continuously, but harvesting that energy constantly will only enable transmissions of about 10 feet today. Range will be the big challenge for making this technology successful.

So we wont be seeing them anytime soon unfortunately.

Recycling of materials is always a concern, especially now that the use of Lithium-ion is increasing. Financial Times (FT) recently did a good summary of all the companies trying to recycle Lithium, Cobalt, etc.

Mr Kochhar estimates over 11m tonnes of spent lithium-ion batteries will be discarded by 2030. The company is looking to process 5,000 tonnes a year to start with and eventually 250,000 tonnes — a similar amount to a processing plant for mined lithium, he said.

The battery industry currently uses 42 percent of global cobalt production, a critical metal for Lithium-ion cells. The remaining 58 percent is used in diverse industrial and military applications (super alloys, catalysts, magnets, pigments…) that rely exclusively on the material.

According to Wikipedia, The purpose of the Cobalt (Co) within the LIBs is to act as a sort of bridge for the lithium ions to travel on between the cathode (positive end of the battery) and the anode (the negative end). During the charging of the battery, the cobalt is oxidized from Coᶾ⁺ to Co⁴⁺. This means that the transition metal, cobalt, has lost an electron. During the discharge of the battery the cobalt is reduced from Co⁴⁺ to Coᶾ⁺. Reduction is the opposite of oxidation. It is the gaining of an electron and decreases the overall oxidation state of the compound. Oxidation and reduction reactions are usually coupled together in a series of reactions known as red-ox (reduction-oxidation) reactions. This chemistry was utilized by Sony in 1990 to produce lithium ion cells.

From Treehugger: An excellent investigative piece by the Washington Post called “The cobalt pipeline: From dangerous tunnels in Congo to consumers’ mobile tech” explores the source of this valuable mineral that everyone relies on, yet knows little about.

“Lithium-ion batteries were supposed to be different from the dirty, toxic technologies of the past. Lighter and packing more energy than conventional lead-acid batteries, these cobalt-rich batteries are seen as ‘green.’ They are essential to plans for one day moving beyond smog-belching gasoline engines. Already these batteries have defined the world’s tech devices.

“Smartphones would not fit in pockets without them. Laptops would not fit on laps. Electric vehicles would be impractical. In many ways, the current Silicon Valley gold rush — from mobile devices to driverless cars — is built on the power of lithium-ion batteries.”

What The Post found is an industry that’s heavily reliant on ‘artisanal miners’ or creuseurs, as they’re called in French. These men do not work for industrial mining firms, but rather dig independently, anywhere they may find minerals, under roads and railways, in backyards, sometimes under their own homes. It is dangerous work that often results in injury, collapsed tunnels, and fires. The miners earn between $2 and $3 per day by selling their haul at a local minerals market.

There is a big potential for reducing waste and improving lives, hopefully we will see some developments on this front soon.

Debugging Problem: Same Phones With Different Signal Levels?

I have discussed this problem in past, based on questions asked on various fora (example). Here is a video I made some weeks back. Will be interested to know what other reasons people can come up with 😊.

5G Core Network, System Architecture & Registration Procedure

The 5G System architecture (based on 3GPP TS 23.501: System Architecture for the 5G System; Stage 2) consists of the following network functions (NF). The functional description of these network functions is specified in clause 6.
- Authentication Server Function (AUSF)
- Core Access and Mobility Management Function (AMF)
- Data network (DN), e.g. operator services, Internet access or 3rd party services
- Structured Data Storage network function (SDSF)
- Unstructured Data Storage network function (UDSF)
- Network Exposure Function (NEF)
- NF Repository Function (NRF)
- Network Slice Selection Function (NSSF)
- Policy Control function (PCF)
- Session Management Function (SMF)
- Unified Data Management (UDM)
- Unified Data Repository (UDR)
- User plane Function (UPF)
- Application Function (AF)
- User Equipment (UE)
- (Radio) Access Network ((R)AN)

As you can see, this is slightly more complex than the 2G/3G/4G Core Network Architecture.

Alan Carlton, Vice President, InterDigital and Head of InterDigital International Labs Organization spanning Europe and Asia provided a concise summary of the changes in 5G core network in ComputerWorld:

Session management is all about the establishment, maintenance and tear down of data connections. In 2G and 3G this manifested as the standalone General Packet Radio Service (GPRS). 4G introduced a fully integrated data only system optimized for mobile broadband inside which basic telephony is supported as just one profile.

Mobility management as the name suggests deals with everything that needs doing to support the movement of users in a mobile network. This encompasses such functions as system registration, location tracking and handover. The principles of these functions have changed relatively little through the generations beyond optimizations to reduce the heavy signaling load they impose on the system.

The 4G core network’s main function today is to deliver an efficient data pipe. The existence of the service management function as a dedicated entity has been largely surrendered to the “applications” new world order. Session management and mobility management are now the two main functions that provide the raison d’etre for the core network.

Session management in 4G is all about enabling data connectivity and opening up a tunnel to the world of applications in the internet as quickly as possible. This is enabled by two core network functions, the Serving Gateway (SGW) and Packet Data Gateway (PGW). Mobility management ensures that these data sessions can be maintained as the user moves about the network. Mobility management functions are centralized within a network node referred to as Mobility Management Entity (MME). Services, including voice, are provided as an “app” running on top of this 4G data pipe. The keyword in this mix, however, is “function”. It is useful to highlight that the distinctive nature of the session and mobility management functions enables modularization of these software functions in a manner that they can be easily deployed on any Commercial-Off-The-Shelf (COTS) hardware.

The biggest change in 5G is perhaps that services will actually be making a bit of a return...the plan is now to deliver the whole Network as a Service. The approach to this being taken in 3GPP is to re-architect the whole core based on a service-oriented architecture approach. This entails breaking everything down into even more detailed functions and sub-functions. The MME is gone but not forgotten. Its former functionality has been redistributed into precise families of mobility and session management network functions. As such, registration, reachability, mobility management and connection management are all now new services offered by a new general network function dubbed Access and Mobility Management Function (AMF). Session establishment and session management, also formerly part of the MME, will now be new services offered by a new network function called the Session Management Function (SMF). Furthermore, packet routing and forwarding functions, currently performed by the SGW and PGW in 4G, will now be realized as services rendered through a new network function called the User Plane Function (UPF).

The whole point of this new architectural approach is to enable a flexible Network as a Service solution. By standardizing a modularized set of services, this enables deployment on the fly in centralized, distributed or mixed configurations to enable target network configurations for different users. This very act of dynamically chaining together different services is what lies at the very heart of creating the magical network slices that will be so important in 5G to satisfy the diverse user demands expected. The bottom line in all this is that the emphasis is now entirely on software. The physical boxes where these software services are instantiated could be in the cloud or on any targeted COTS hardware in the system. It is this intangibility of physicality that is behind the notion that the core network might disappear in 5G.

3GPP TS 23.502: Procedures for the 5G System; Stage 2, provides examples of signalling for different scenarios. The MSC above shows the example of registration procedure. If you want a quick refresher of LTE registration procedure, see here.

I dont plan to expand on this procedure here. Checkout section "4.2.2 Registration Management procedures" in 23.502 for details. There are still a lot of FFS (For further studies 😉) in the specs that will get updated in the coming months.


Further Reading:

• 3GPP TR 23.799: Study on Architecture for Next Generation System
• 3GPP TS 23.501: System Architecture for the 5G System; Stage 2
• 3GPP TS 23.502: Procedures for the 5G System; Stage 2