Tuesday, 5 December 2017

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:


    Sunday, 3 December 2017

    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.

    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.


    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:

    Friday, 1 December 2017

    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.

    Monday, 27 November 2017

    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.



    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.


    Thursday, 23 November 2017

    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:



    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.

    Tuesday, 21 November 2017

    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)

    Thursday, 16 November 2017

    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.




    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 ðŸ˜‰

    Further reading:

    Wednesday, 15 November 2017

    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:

    Friday, 10 November 2017

    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.



    Further Reading:



    Thursday, 9 November 2017

    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.