VoLTE Roaming: LBO, S8HR or HBO

There was an interesting discussion on different roaming scenarios in the LTE Voice Summit on 29th, 30th Sep. in London. The above picture provides a brief summary of these well known options. I have blogged about LBO/RAVEL here and S8HR here. A presentation by NTT Docomo in a GSMA webinar here provides more details on these architectures (slide 29 onwards - though it is more biased towards S8HR).

Ajay Joseph, CTO, iBasis gave an interesting presentation that highlighted the problems present in both these approaches.

In case of LBO, the biggest issue is that the home operator need to do a testing with each roaming partner to make sure VoLTE roaming works smoothly. This will be time consuming and expensive.

In case of S8HR, he provided a very good example. Imagine a VoLTE subscriber from USA is visiting Singapore. He now needs to make a phone call to someone in Indonesia (which is just next to Singapore). The flow of data would be all the way from Singapore to USA to Indonesia and back. This can introduce delays and impact QoE. The obvious advantage of S8HR is that since the call setup and media go to Home PMN (Public Mobile Network), no additional testing with the Visited PMN is required. The testing time is small and rollouts are quicker.

iBasis are proposing a solution called Hub Breakout (HBO) which would offer the best of LBO and S8HR. Each VoLTE operator would need to test their interoperability only with iBasis. Emergency calls and lawful intercept that does not work with S8HR would work with the HBO solution.

While I agree that this is a good solution, I am sure that many operators would not use this solution and there may be other solutions proposed in due course as well. Reminds me of this XKCD cartoon:

Anyway, here is the iBasis presentation:

S8HR: Standardization of New VoLTE Roaming Architecture

VoLTE is a very popular topic on this blog. A basic VoLTE document from Anritsu has over 40K views and my summary from last years LTE Voice summit has over 30K views. I assume this is not just due to the complexity of this feature.

When I attended the LTE Voice summit last year, of the many solutions being proposed for roaming, 'Roaming Architecture for Voice over LTE with Local Breakout (RAVEL)' was being touted as the preferred solution, even though many vendors had reservations.

Since then, GSMA has endorsed a new VoLTE roaming architecture, S8HR, as a candidate for VoLTE roaming. Unlike previous architectures, S8HR does not require the deployment of an IMS platform in VPLMN. This is advantageous because it shortens time-to-market and provides services universally without having to depend on the capability of VPLMN.



Telecom Italia has a nice quick summary, reproduced below:

S8HR simplicity, however, is not only its strength but also its weakness, as it is the source of some serious technical issues that will have to be solved. The analysis of these issues is on the Rel13 3GPP agenda for the next months, but may overflow to Rel14. Let’s see what these issues are, more in detail:

Regulatory requirements - S8HR roaming architecture needs to meet all the current regulatory requirements applicable to voice roaming, specifically:

• Support of emergency calls - The issues in this context are several. For example, authenticated emergency calls rely on the existence if an IMS NNI between VPLMN and HPLMN (which S8HR does not provide); conversely, the unauthenticated emergency calls, although technically feasible in S8HR, are allowed only in some Countries subject to the local regulation of VPLMN. Also, for a non-UE-detectable IMS Emergency call, the P-CSCF in the HPLMN needs to be capable of deciding the subsequent action (e.g. translate the dialed number and progress the call or reject it with the indication to set up an emergency call instead), taking the VPLMN ID into account. A configuration of local emergency numbers per Mobile Country Code on P-CSCF may thus be needed.
• ­Support of Lawful Interception (LI) & data retention for inbound roamers in VPLMN -  S8HR offers no solution to the case where interception is required in the VPLMN for inbound roamers. 3GPP is required to define a solution that fulfill such vital regulatory requirement, as done today in circuit switched networks. Of course VPLMN and HPLMN can agree in their bilateral roaming agreement to disable confidentiality protection to support inbound roamer LI but is this practice really viable from a regulatory point of view?

Voice call continuity – The issue is that when the inbound roamers lose the LTE coverage to enter into  a 2G/3G CS area, the Single Radio Voice Call Continuity (SRVCC) should be performed involving the HPLMN in a totally different way than current specification (i.e. without any IMS NNI being deployed).
Coexistence of LBO and S8HR roaming architectures will have to be studied since an operator may need to support both LBO and S8HR VoLTE roaming architecture options for roaming with different operators, on the basis of bilateral agreement and depending on the capability.
Other issues relate to the capability of the home based S-CSCF and TAS (Telephony Application Server) to be made aware about the VPLMN identity for charging purposes and to enable the TAS to subsequently perform communication barring supplementary services. Also, where the roaming user calls a geo-local number (e.g. short code, or premium numbers), the IMS entities in HPLMN must do number resolution to correctly route the call.
From preliminary discussions held at Working Group level in SA2 (architecture) and SA3 (security) in April, it was felt useful to create a new 3GPP Technical Report to perform comprehensive technical analysis on the subject. Thus it is expected that the discussions will continue in the next months until the end of 2015 and will overheat Release 13 agenda due to their commercial and “political” nature. Stay tuned to monitor the progress of the subject or contact the authors for further information!

NTT Docomo also did some trials back in February and got some brilliant results:

In the trials, DOCOMO and KT achieved the world's first high-definition voice and video call with full end-to-end quality of service. Also, DOCOMO and Verizon achieved the world's first transoceanic high-definition VoLTE roaming calls. DOCOMO has existing commercial 3G and 4G roaming relations with Verizon Wireless and KT.

The calls were made on an IP eXchange (IPX) and network equipment to replicate commercial networks. With only two months of preparation, which also proved the technology's feasibility of speedy commercialization, the quality of VoLTE roaming calls using S8HR architecture over both short and long distances was proven to be better than that of existing 3G voice roaming services.

In fact, NTT Docomo has already said based on the survery from GSMA's Network 2020 programme that 80% of the network operators want this to be supported by the standards and 46% of the operators already have a plan to support this.

The architecture has the following technical characteristics:
(1) Bearers for IMS services are established on the S8 reference point, just as LTE data roaming.
(2) All IMS nodes are located at Home Public Land Mobile Network (HPLMN), and all signaling and media traffic for the VoLTE roaming service go through HPLMN.
(3) IMS transactions are performed directly between the terminal and P-CSCF at HPLMN. Accordingly, Visited Public Land Mobile Network (VPLMN) and interconnect networks (IPX/GRX) are not service-aware at the IMS level. The services can only be differentiated by APN or QoS levels.

These three technical features make it possible to provide all IMS services by HPLMN only and to minimize functional addition to VPLMN. As a result, S8HR shortens the time-to-market for VoLTE roaming services.

Figure 2 shows the attach procedure for S8HR VoLTE roaming. From Steps 1 to 3, there is no significant difference from the LTE data roaming attach procedure. In Step 4, HSS sends an update location answer message to MME. In order for the MME to select the PGW in HPLMN (Step 5), the MME must set the information element VPLMN Dynamic Address “Allowed,” which is included in the subscribed data, to “Not Allowed.” In Step 6, the bearer for SIP signaling is created between SGW and PGW with QCI=5. MME sends an attach accept message to the terminal with an IMS Voice over PS Session Support Indication information element, which indicates that VoLTE is supported. The information element is set on the basis of the MME’s internal configuration specifying whether there is a VoLTE roaming agreement to use S8HR. If no agreement exists between two PLMNs, the information element will not be set.

The complete article from the NTT Docomo technical journal is embedded

5G: A 2020 Vision

I had the pleasure of speaking at the CW (Cambridge Wireless) event ‘5G: A Practical Approach’. It was a very interesting event with great speakers. Over the next few weeks, I will hopefully add the presentations from some of the other speakers too.

In fact before the presentation (below), I had a few discussions over the twitter to validate if people agree with my assumptions. For those who use twitter, maybe you may want to have a look at some of these below:

5G is coming, maybe much earlier than you expect it to. There is a race to be first. Come... http://t.co/BQUR5p3bpk pic.twitter.com/z3cOD7Xv2O
— eXplanoTech (@eXplanoTech) January 30, 2015

@disruptivedean @ericsson Re 2% only cellular, I was discussing this the other day. Too many competing techs. pic.twitter.com/Z7s6wqxkBM
— Zahid Ghadialy (@zahidtg) January 26, 2015

Spectrum Bands Summary - Can anyone point me to a better picture? (Cc @open_spectrum @StevenJCrowley @elenaneira) pic.twitter.com/IkBhtQubSj
— Zahid Ghadialy (@zahidtg) January 19, 2015

Anyway, here is the presentation.

 

5G: A 2020 Vision from eXplanoTech

M2M embedded UICC (eSIM) Architecture and Use Cases

Machine-to-Machine UICC, also known as M2M Form Factor (MFF) and is often referred to as embedded SIM (eSIM) is a necessity for the low data rate M2M devices that are generally small, single contained unit that is also sealed. The intention is that once this M2M device is deployed, then there is no need to remove the UICC from it. There may be a necessity to change the operator for some or the other reason. This gives rise to the need of multi-operator UICC (SIM) cards.

The GSMA has Embedded SIM specifications available for anyone interested in implementing this. There are various documents available on the GSMA page for those interested in this topic further.

While the complete article is embedded below, here is an extract of the basic working from the document:

A eUICC is a SIM card with a Remote Provisioning function, and is designed not to be removed or changed. It is able to store multiple communication profiles, one of which is enabled (recognized by the device and used for communication). The network of the MNO in the enabled profile is used for communication. Profiles other than the enabled profile are disabled (not recognized by the device). With conventional SIM cards, the ICCID is used as the unique key to identify the SIM card, but with eUICC, the ICCID is the key used to identify profiles, and a new ID is defined, called the eUICCID, which is used as the unique key for the eSIM

GSMA defines two main types of profile.
1) Provisioning Profile: This is the communication profile initially stored in the eUICC when it is shipped. It is a limited-application communication profile used only for downloading and switching Operational Profiles, described next.
2) Operational Profile: This is a communication profile for connecting to enterprise servers or the Internet. It can also perform the roles provided by a Provisioning profile

An eSIM does not perform profile switching as a simple IC card function, but rather switches profiles based on instructions from equipment called a Subscription Manager. A Subscription Manager is maintained and managed by an MNO. The overall eSIM architecture, centering on the Subscription Manager, is shown in Figure 3, using the example of switching profiles within the eUICC.

An eUICC must have at least one profile stored in it to enable OTA functionality, and one of the stored profiles must be enabled. The enabled profile uses the network of MNO A for communication. When the user switches profiles, a switch instruction is sent to the Subscription Manager. At that time, if the profile to switch to is not stored in the eUICC, the profile is first downloaded. When it receives a switch instruction, the eUICC performs a switch of the enabled profile as an internal process.

After the switch is completed, it uses the network of MNO B to send notification that the switch has completed to the Subscription Manager, completing the process. The same procedure is used to switch back to the original MNO A, or to some other MNO C.

Anyway, here is the complete paper on NTT Docomo website.

2015 will finally be the year of Voice over LTE (VoLTE)

On 4th Nov. 2009, the One Voice initiative was published by 12 companies including AT&T, Orange, Telefonica, TeliaSonera, Verizon, Vodafone, Alcatel-Lucent, Ericsson, Nokia Siemens Networks, Nokia, Samsung and Sony Ericsson. These all agreed that the IMS based solution, as defined by 3GPP, is the most applicable approach to meet their consumers expectations for service quality, reliability and availability when moving from existing CS based voice services to IP based LTE services.

On 15th Feb 2010, GSMA announced that it has adopted the work of the One Voice initiative to drive the global mobile industry towards a standard way of delivering voice and messaging services for LTE. The GSMA’s VoLTE initiative was supported by more than 40 organisations from across the mobile ecosystem, including many of the world’s leading mobile communication service providers, handset manufacturers and equipment vendors, all of whom support the principle of a single, IMS-based voice solution for next-generation mobile broadband networks. This announcement was also supported by 3GPP, Next Generation Mobile Networks alliance (NGMN) and the International Multimedia Teleconferencing Consortium (IMTC).

GSMA has produces various reference documents that map to the 3GPP standards documents as can be seen above.

As per GSA: 71 operators are investing in VoLTE studies, trials or deployments, including 11 that have commercially launched HD voice service. The number of HD voice launches enabled by VoLTE is forecast to reach 19 by end-2014 and then double in 2015. In July 2014 GSA confirmed 92 smartphones (including carrier and frequency variants) support VoLTE, including products by Asus, Huawei, LG, Pantech, Samsung and Sony Mobile. The newly-announced Apple iPhone 6 & 6 Plus models support VoLTE.

Things are also moving quickly with many operators who have announced VoLTE launches and are getting more confident day by day. Du, Dubai recently announced Nokia as VoLTE partner. KDDI, Japan is launching au VoLTE in December. Telstra, Australia has already been doing trials and plans to launch VoLTE network in 2015. Finally, Verizon and AT&T will have interoperable VoLTE calls in 2015.

Below is my summary from the LTE Voice Summit 2014. Let me know if you like it.

Quick Summary of LTE Voice Summit 2014 #LTEVoice from eXplanoTech

International LTE Data and VoLTE Roaming - NTT Docomo

Quick recap of the Bearer Architecture: Remember the interface between S-GW and P-GW is known as S5/S8. S5 in case the S-GW and P-GW are part of the same network (non-roaming case) and S8 in case where P-GW belongs to another network than S-GW (roaming case). The S5/S8 interfaces are generally exactly the same. There is a possibility of different types of S5/S8 interfaces like GTP based and PMIP based but lets not discuss that here.

NTT Docomo published an excellent article in their magazine recently showing the different approaches to International Data roaming.

The different scenarios above are based on the guidelines provided in GSMA PRD IR.88. Each operator has to adopt one of the scenarios above, NTT Docomo has selected scenario 4. The Home PLMN (HPLMN) and the Visited PLMN (VPLMN) connect via IP eXchange (IPX).

As can be seen above, the MME in VPLMN communicates with HSS in HPLMN using Diameter Edge Agent (DEA).

Finally, it is well known that NTT Docomo is not launching VoLTE untill 2015. The above is their proposal on how they handle VoLTE while in Japan and when roaming.

The paper is an interesting read, embedded below:

NTT Docomo: Implementing LTE International Data Roaming from Zahid Ghadialy

Another article worth a read is the VoLTE roaming with RAVEL here.

VoLTE Roaming with RAVEL (Roaming Architecture for Voice over IMS with Local Breakout)

Voice over LTE or VoLTE has many problems to solve. One of the issues that did not have a clear solution initially was Roaming. iBasis has a whitepaper on this topic here, from which the above picture is taken. The following is what is said above:

The routing of international calls has always been a problem for mobile operators. All too often the answer—particularly in the case of ‘tromboning’ calls all the way back to the home network—has been inelegant and costly. LTE data sessions can be broken out locally, negating the need for convoluted routing solutions. But in a VoIMS environment all of the intelligence that decides how to route the call resides in the home network, meaning that the call still has to be routed back.

The industry’s solution to this issue is Roaming Architecture for Voice over LTE with Local Breakout (RAVEL). Currently in the midst of standardisation at 3GPP, RAVEL is intended to enable the home network to decide, where appropriate, for the VoIMS call to be broken out locally. 

Three quarters of respondents to the survey said they support an industry-wide move to RAVEL for VoLTE roaming. This is emphatic in its enthusiasm but 25 per cent remains a significant share of respondents still to be convinced. Just over half of respondents said they plan to support VoIMS for LTE roaming using the RAVEL architecture, while 12.3 per cent said they would support it, but not using RAVEL.

Until RAVEL is available, 27.4 per cent of respondents said they plan to use home-routing for all VoLTE traffic, while just under one fifth said they would use a non-standard VoLTE roaming solution.

Well, the solution was standardised in 3GPP Release-11. NTT Docomo has an excellent whitepaper (embedded below) explaining the issue and the proposed solution.

In 3GPP Release 11, the VoLTE roaming and interconnection architecture was standardized in cooperation with the GSMA Association. The new architecture is able to implement voice call charging in the same way as circuit-switched voice roaming and interconnection models by routing both C-Plane messages and voice data on the same path. This was not possible with the earlier VoLTE roaming and interconnection architecture.

Anyway, here is the complete whitepaper

NTT Docomo: VoLTE Roaming and Interconnection Standard Technology from Zahid Ghadialy

Security and other development on the Embedded SIM

Its no surprise that GSMA has started working on Embedded SIM specifications. With M2M getting more popular every day, it would make sense to have the SIM (or UICC) embedded in them during the manufacturing process. The GSMA website states:

The GSMA’s Embedded SIM delivers a technical specification to enable the remote provisioning and management of Embedded SIMs to allow the “over the air” provisioning of an initial operator subscription and the subsequent change of subscription from one operator to another.

The Embedded SIM is a vital enabler for Machine to Machine (M2M) connections including the simple and seamless mobile connection of all types of connected vehicles. In the M2M market the SIM may not easily be changed via physical access to the device or may be used in an environment that requires a soldered connection, thus there is a need for ‘over the air’ provisioning of the SIM with the same level of security as achieved today with traditional “pluggable” SIM. It is not the intention for the Embedded SIM to replace the removable SIM currently used as the removable SIM still offers many benefits to users and operators in a number of different ways – for example, the familiarity of the form factor, easy of portability, an established ecosystem and proven security model.

The last time I talked about embedded SIM was couple of years back, after the ETSI security workshop here. Well, there was another of these workshops recently and an update to these information.

The ETSI presentation is not embedded here but is available on Slideshare here. As the slide says:

An embedded UICC is a “UICC which is not easily accessible or replaceable, is not intended to be removed or replaced in the terminal, and enables the secure changing of subscriptions” (ETSI TS 103 383)

Finally, Embedded SIM should not be confused with Soft-SIM. My last post on Soft-SIM, some couple of years back here, has over 15K views which shows how much interest is there in the soft SIM. As the slide says:

Soft or Virtual SIM is a completely different concept that does not use existing SIM hardware form factors and it raises a number of strong security issues:

• Soft SIM would store the Operator secret credentials in software within the Mobile device operating system - the same system that is often attacked to modify the handset IMEI, perform SIM-Lock hacking and ‘jail-break’ mobile OS’s
• Operators are very concerned about the reduction in security of their credentials through the use of Soft SIM. Any SIM approach not based on a certified hardware secure element will be subject to continual attack by the hacking community and if compromised result in a serious loss of customer confidence in the security of Operator systems
• Multiple Soft SIM platforms carrying credentials in differing physical platforms, all requiring security certification and accreditation would become an unmanageable overhead – both in terms of resource, and proving their security in a non-standardised virtual environment

The complete GSMA presentation is as follows:

GSMA Embedded SIM from Zahid Ghadialy

You may also like my old paper:

• M2M, Cellular and Small Cells

Rich Communication Suite (RCS)

I have heard quite a bit about Rich Communication Suite (RCS) recently. It was supposed to start become popular by 2011 but Infonetics puts it as a little too late to become mass market anytime soon in a recent report. The new report forecasts that there would be around 6.8 million RCS subscribers worldwide by end of 2012.

Dean Bubley from Disruptive Wireless released a report some months back saying that RCS is a bit too late and inflexible and the built-in assumptions have problems which wont make it a mass market technology.

Anyway, I decided to explore the technology a bit to understand it better. Before we start digging into this, the following Youtube Video gives a good overview of what RCS is supposed to be:

The following article gives a good summary of RCS as of now:

The GSMA is welcoming a new version of Rich Communication Suite (RCS) that will enable mobile phone customers to use instant messaging (IM), live video sharing and file transfer across any device on any network operator. Deutsche Telekom, Orange, Telecom Italia, Telefonica and Vodafone intend to commercially launch RCS across several European markets from late 2011, and additional operators are expected to launch later in 2012.

Once adopted, Rich Communication Suite – e* (RCS-e) will enable customers to use these enhanced communication services across mobile networks in a simpler and more intuitive way. It is based on a specification put forward by Bharti, Deutsche Telekom, Orange, Orascom Telecom, SK Telecom, Telecom Italia, Telefonica, Telenor and Vodafone which aims to lower the hurdle and speed up the market introduction and adoption of these services.

With RCS-e, customers will be able to use IM, share live video and share files such as photos simultaneously during calls, regardless of the network or device used. RCS-e will enable users to communicate in a very natural way, much like with GSM voice and text today, and will also offer the simplicity and security customers expect from mobile operator services.

As customers open their address book, they will be able to see which communication services are available to them. They can then choose their preferred communications option. For example, a customer would see if their contact is in an area with 3G coverage and is able to receive video.

The participating operators will work with handset suppliers to ensure the service is integrated into the address books of devices, so that customers will not have to download any additional software or technically configure their handsets in order to benefit from the enhanced experience.

“Mobile operators are committed to giving their customers greater choice in the way they communicate with one and other,” said Rob Conway, CEO and Member of the Board of the GSMA. “We welcome the pragmatic approach taken by these operators to accelerate the commercialisation of RCS and simplify the experience for mobile customers and we will work to adopt this specification within the RCS initiative.”

The RCS specification is designed to be interoperable between all operators and devices, giving customers greater choice in how they communicate. The new RCS-e is the result of extensive trials and is a subset of the current RCS 2.0 standard with enhancements. It is focused on extending the principles of voice and SMS calls to deliver an advanced set of interoperable data-centric communications services.

* RCS-e is a new enhanced version of the RCS specification which is based on the use across networks of IP Multimedia Subsystem (IMS) technology, an architectural framework for delivering Internet Protocol (IP) multimedia services.

The following presentation provides a bit more detail

Rich Communication Suite (RCS)

View more presentations from Zahid Ghadialy

Eduardo Martin's blog provides some more insight into the RCS Releases:

RCS has 3 releases, each upgrades the previous one. I will focus on SIP Presence only, but RCS touches more than SIP Presence, it also works other services such as IM.

RCS Release 1 evolves around the concept of the Enhanced Address Book (EAB), an evolution of the usual address book. In short the address book is decorated with enriched information, coming from different services. This plays nicely with today's wishes for cloud stored information, unified social networks status updates, contact content such as portrait icons. I'm not going into technical details, but I for sure am someone who is aware of the design issues around SIP Presence, its hard time scaling due to huge traffic, the dozens of ugly workarounds to make it work, and RCS is a nice step forward into the right direction, there are simple decisions that deeply simplify the network design, making it more like "old" presence networks, which simply work. One remark, it takes quite an effort to define this endorsing IMS and OMA, 27 pages of functional description, plus 39 of technical realization, it should be a lesson for everyone in these standard bodies when defining more extensions or new versions.

The RCS Release 2 effort focuses on enabling access to rich communication services from a wider range of devices. In short it tells that the user has multiple devices, for instance a mobile phone and a PC, possibly concurring for services, and adapts Release 1 for that. It also introduces the Network Address Book, which is just the realization that the EAB needs to be in the network and sync the multiple user devices.

The RCS Release 3 mostly consolidates Release 2 features, and adds some minor enhancements, such as preparing the network for different usages of it, for instance users with devices, which are not connected to mobile network, instead only have broadband connections. In my humble opinion a very important and positive decision, it's about time to consider these scenarios and find out new opportunities. It is weird to say this, but the fact that the industry finally acknowledges that content sharing between two users may happen off the voice/video session is a victory, welcome to the world not session centric.

The RCS specs are available here.

Voice over LTE - GSMA Presentation

Voice over LTE

View more presentations from zahidtg.

Updates from GSMA Asia Mobile Congress 09 - Day 2

Summary of interesting facts from the GSMA Mobile Asia Congress 09, Via Tomi Ahonen's, Communities Dominate Brands:

• 55% of Japan has migrated past 3G to 3.5G
• Japanese mobile content industry is worth 14 Billion dollars annually
• 50% of mobile data in Japan is consumed in the home, the peak time for mobile data consumption is between 9 PM and 10 PM; and smartphone users consume 10 times more data than non-smartphone users.
  
• Japan's Softbank will turn off their 2G network already in March of next year, 2010.
• Allen Lew, Singtel's CEO, said that in Singapore almost 50% of smartphone owners are shifting web surfing activity away from PCs.
  
• Jon Fredrik Baksaas, Telenor's President and CEO, spoke about the eco-friendly initiatives they have, such as solar powered cellular network base stations etc, but an interesting tidbit that came out, is that in Europe, Telenor has installed 870,000 household electricity meters that are remote digital meters and operate on the GSM cellular network, in Sweden. As Sweden's population is only about 7 million people that is probably a third of all households.
  
• Rajat Mukarji of Idea (one of India's largest mobile operators), told us of the Indian market, where the average price of a voice minute is 1 cent (US). He Mr Mukarji also said that in India mobile is the first screen, not the fourth screen; and mobile is the first internet connectivity opportunity for most people of India.
• Tony Warren, GM of Regulatory Affairs at Telstra, told that 60% of phones in Australia are 3G already, and over half of mobile data is now non-SMS type of more advanced mobile data. And he said that MMS is experiencing enormous growth, grew 300% in the past year.

You can read the summary of first day here.

Read the complete report here.

Updates from GSMA Asia Mobile Congress 09 - Day 1

Summary of interesting facts from the GSMA Mobile Asia Congress 09, Via Tomi Ahonen's, Communities Dominate Brands:

• According to Rob Conway, CEO of the GSM Association, the number of subscribers will grow to 8 Billion (not sure when though).
• China Unicom, China's second largest mobile operator with 142 million subscribers - bigger than AT&T and Sprint put together.
• Bharti Telecom of India has over 110 million subscribers
• According to Manoj Kohli, the CEO of Bharti Telecom, India already 20% of all mobile phone owners have 2 or more subscriptions. He also told us that as India will add 500 million new subscribers by the time frame of 2014-2015. India is currently adding 10 million new mobile subscribers every month. And most revealingly, he said that in India the customers will go from 'no internet' directly to 'mobile internet'.
• According to Wang Jianzhou the Chairman and CEO of China Mobile, the world's biggest mobile operator with over 500 million subscribers, on the Chinese 3G standard of TD-SCDMA, they already have 3G phones being sold that cost about 1,000 Yuan, or about 130 US dollars. The average China Mobile customer spends 1 minute per day on voice calls, but sends on average 3.6 SMS text messages per day.
• According to Yamada-san, the President and CEO of Japan's NTT DoCoMo, on NTT DoCoMo's network, today already 42% of their total revenues come from non-voice data services. NTT DoCoMo is so far in its migration of its customer base from 2G to 3G, they will terminate 2G in March of 2011.
• Yamada-san also told of their new 3G video TV service, they call BeeTV. BeeTV is special in that it is optimized for the small screen, not re-purposed video content from TV and the internet. BeeTV in only six months has achieved 800,000 paying subscribers - who pay 315 Yen per month (about 3 USD).
• Yamada-San's 20 minute presentation also mentioned that NTT DoCoMo's i-Consierge service (yes, think of it as your personal butler, the phone learns your habits and starts to help you with your life, this is like magic) has 2.3 million paying subscribers one year from launch. Their i-Channel idle screen invention is spreading and they have launched it also with their partner in India, Tata, who offer Cricket game updates via the idle screen using i-Channel.
• Japan's mobile advertising market in 2008 was worth 900 million dollars.
• Grameenphone and Huawei won the 'Green Mobile' award for their 'green' network initiatives.

Read the complete blog here.

GPRS Roaming eXchange (GRX) for LTE/EPS Networks

The GSM Association (GSMA) has came to the realization that GPRS roaming based on bilateral relationships between individual GPRS operators is incredibly complex and expensive to maintain, in particular if the number of roaming partners is high. In fact, each operator will have to have N(N - 1) dedicated links to other operators (given that N is the global numbers of operators for which roaming should be supported). The GSMA has therefore recommended the use of a GPRS Roaming eXchange (GRX) for the Inter-PLMN GPRS roaming scenario.

The GRX is built on a private or public IP backbone and transports GPRS roaming traffic via the GTP between the visited and the home PLMN (Figure above). A GRX service provider has a network consisting of a set of routers and the links connecting to the GPRS networks. Moreover, the GRX network will have links connecting to other GRX nodes to support GRX peering between networks.

The GRX service provider acts as a hub, therefore allowing a GPRS operator to interconnect with each roaming partner without the need for any dedicated connections. This allows faster implementation of new roaming relations, faster time to market for new operators, and better scalability since an operator can start with low-capacity connections to the GRX and upgrade them depending on the bandwidth and quality requirements of the traffic. Other benefits of GRX are as follows:

Support of QoS: This aspect that will be very important for the GPRS services and, in particular, for the transition to 3G systems.

Security: The interconnection between the home operator and the visited operator uses the private GRX networks, hence does not require the overhead of maintaining expensive IPSEC tunnels over the public Internet.

DNS support: Through GRX it is possible to support a worldwide ".gprs" DNS root, where the various GRX operators will collaborate in managing the root and each operator's DNS servers will be connected to such roots to provide translation of DNS names specific to one operator.

In conclusion, GRX is introduced for GPRS roaming to facilitate the network operators for the interconnection between networks to support roaming and will play a very important role for the transition to third-generation systems.

In the LTE World Summit, Alex Sinclair, Chief Technology Officer, GSMA mentioned about the important role GRX will play in the LTE networks. The figure below are his views on GRX.

Diagram and Initial text Reference: IP in Wireless Networks By Basavaraj Patil, et al.

More information on GRX is available in GSM Association IR.34 document.