Multi-SIM Terminology

This new video and presentation looks at the operation and terminology associated with multiple SIMs in mobile cellular devices.

Slides and video embedded below introduces the concept of transceivers, active and standby states and then look at Dual Sim Single & Dual Standby (DSSS / DSDS), Dual SIM Dual Active (DSDA), Triple SIM Triple Standby (TSTS) and finally, Quad SIM Quad Standby (QSQS) in case of four SIM cards.

Beginners: Multi-SIM Operation from 3G4G

Related Posts:

• The 3G4G Blog: Embedded SIM (eSIM) and Integrated SIM (iSIM)
• 3G4G: MNO, MVNO, MVNA, MVNE: Different types of mobile operators
• The 3G4G Blog: The Journey from Communications Service Provider (CSP) to Digital Service Provider (DSP)
• The 3G4G Blog: M2M embedded UICC (eSIM) Architecture and Use Cases

Embedded SIM (eSIM) and Integrated SIM (iSIM)

It's been a while since I wrote detailed posts explaining UICC and SIM cards. Since then the SIM cards have evolved from Mini SIM to Micro SIM and Nano SIM. They are evolving even further, especially for M2M / IoT devices as embedded SIM (eSIM or eUICC) and integrated SIM (iSIM).

Embedded SIMs (eSIMs) or embedded Universal Integrated Circuit Cards (eUICCs) are physical SIMs that are soldered into the device and enable storage and remote management of multiple network operator profiles (remote SIM provisioning). The form factor of eSIM is known as MFF2.

The integrated SIMs (iSIMs) moves the SIM from a separate chip into a secure enclave alongside the application processor and cellular radio on a purpose-built system on a chip (SoC).

We made a short tutorial explaining UICC & SIM and then looking at eSIM, iSIM and how remote SIM provisioning works. The video and slides are embedded below. The slides contain a lot of useful links for further reading.

Beginners: UICC & SIM from 3G4G

Related Posts:

• The 3G4G Blog: Multi-SIM: The Jargon
• The 3G4G Blog: M2M embedded UICC (eSIM) Architecture and Use Cases
• The 3G4G Blog: The Journey from Communications Service Provider (CSP) to Digital Service Provider (DSP)
• 3G4G: MNO, MVNO, MVNA, MVNE: Different types of mobile operators
• The 3G4G Blog: UICC and ISIM (IMS SIM)

Presentations from ETSI Security Week 2019 (#ETSISecurityWeek)

ETSI held their annual Security Week Seminar 17-21 June at their HQ in Sophia Antipolis, France. All the presentations are available here. Here are some I think the audience of this blog will like:

• ETSI Explainer: Overview of Quantum-Safe VPN Techniques
• ETSI Explainer: OneM2M security and Access Control (Rel.3)
• Toward a Safe Quantum Future - Michele Mosca, University of Waterloo
• Cybersecurity Challenges to Europe: Research, Policy and Standardization Effort - Fabio Di Franco, ETSI Cyber Security Landscape
• GSMA: Mobile Telecommunications Security Threat Landscape
• Hacked by Crypto - Bret Jordan, Symantec (Some good details regarding TLS, DNS, ESNI, QUIC, etc.)
• The Automotive Cyber-Threat: What the Future Will Bring Us? - Alain Baritault, iotaBEAM
• What is the Cyber Territory of a Country? - Silke Holtmanns, Nokia Bell Labs
• EU Cybersecurity Act - Martin Schaffer, SGS
• The Impact of ePrivacy Regulation to Cyber-Intelligence: Options to Consider - Ilias Chantzos, Symantec
• Applying AI to Protect 5G Control Traffic - Antonio Pastor, Telefonica I+D
• Applying AI to Detect and Hunt Advanced Attackers - Matt Walmsley, Vectra
• “Real World Adoption of AI in the Field” - Patrick Donegan, HardenStance
• 5G Providing the Secure Platform for Digitalization of Enterprises and Society - Mats Nilsson, Ericsson
• 3GPP 5G Security Vendor’s View - Marcus Wong, Futurewei Technologies (Huawei)
• 5G Security Challenges for Verticals - a Standards View - Ali Rezaki & Anja Jerichow, Nokia Bell Labs
• 5G and other stories: evolving security in an evolving world
• Challenges in Securing the IoT in a Post-Quantum World - Louis Parks, SecureRF
• SIMs, eSIMs and Secure Elements - Remy Cricco, SIMalliance
• Integrated SIMs: The next after Embedded SIM - Dr. Stephan Spitz, IAR Systems
• Deception for Continued Technical Assurance, Alex Tarter, Thales 

New abbreviation for private 5G networks - Non-Public Network (NPN) and security benefits to connected industries and automation cc @3g4gUK #EtsiSecurityWeek pic.twitter.com/Zias9e4XQ6

— Ravishankar Borgaonk (@raviborgaonkar) June 20, 2019

Looks like all presentations were not shared but the ones shared have lots of useful information.


Related Posts:

• Non-public networks (NPN) - Private Networks by another name
• 5G and IoT Security Update from ETSI Security Week 2018
• 5G Security Updates - July 2017
• Telcos: Security Is Not In Your DNA - Patrick Donegan, Principal Analyst, HardenStance

Some interesting April Fools' Day 2019 Technology Jokes

This year April Fools' Day wasn't as fun as the last one, even though it was on Monday. Many tech companies that make effort didn't make one this year. In fact Microsoft went even further and banned any public facing April Fools' pranks. Anyway, here are some of the jokes that I found interesting.

Parallel Wireless 7G Vision
This one was important for me as it features me (Yay!) and also enhanced my video editing skills. Grateful to CW (Cambridge Wireless) for being part of it too.

Parallel Wireless would today like to announces our 7G Vision (#7GVision) - https://t.co/Ffj63NX5F3 - Cambridge Wireless (@cambwireless) will form new Special Interest Group (SIG) to support the 7G Vision with @zahidtg joining the team too. pic.twitter.com/puz3cOoOGn

— Parallel Wireless (@Parallel_tw) April 1, 2019

Video is slightly long but funny hopefully



In short, the focus for the next few years will be do design a 7G logo that can explain the vision and connect with people. Did I mention 7GPPPPP?

"#7G Public Private Political Polling Partnership (7GPPPPP) with many different companies and organizations has also been formed to work on this vision."

Well played @Parallel_tw @cambwireless! ;)#AprilFools https://t.co/Lhxqk2Eifq

— Emanuel Kolta (@EmanuelKolta) April 1, 2019

Google Sssnakes on a map

Google temporarily added a version of the classic game Snakes into its Google Maps app for April Fools’ Day this year.

The company says that the game is rolling out now to iOS and Android users globally today, and that it’ll remain on the app for the rest of the week. It also launched a standalone site to play the game if you don’t have the app.

Jabra Ear bud(dy)

World’s first shared headphone - engineered for shared music moments. The website says:

The headphones come with an ultra-light headband that extends seamlessly to accommodate the perfect fit for every pair of buddies, so you’ll never have to enjoy another music moment alone. The Jabra Earbud(dy)™ comes with a unique Buddy mode that promises a shared music experience that is tailored to suit each person’s preferences. Fans of voice command will be thrilled to know that with just one touch, the Jabra Earbud(dy)™ can connect to dual voice assistant.


T-Mobile Phone BoothE

T-Mobile USA and their CEO John Legere never disappoints. They always come up with something interesting. Here is a video of the prank


From MacRumours:

T-Mobile is again fighting one of the so-called pain points of the wireless industry with the launch of the Phone BoothE, a completely sound-proof and high-tech phone booth that lets T-Mobile customers escape from noisy areas to make their phone calls. Inside the Phone BoothE you can charge your devices, connect to a smart screen called "Magenta Pages" to mirror your smartphone display, and adjust the lighting to take great selfies.

In regards to the name, T-Mobile is taking a shot at AT&T's misleading 5GE label: "The Phone BoothE is an evolution towards the new world of mobility. Like many in the tech and wireless industry today, we decided that by adding an "E" to the name, you would know it's a real technology evolution." 

Although this is an April Fools' Day joke, T-Mobile has actually built the Phone BoothE and deployed them in select locations around New York City, Seattle, and Washington, DC, where anyone will be able to use them. The company on Monday also revealed the T-Mobile Phone BoothE Mobile EditionE, which is more in line with a straightforward April Fools' Day hoax, as it's "literally a magenta cardboard box with a hole in it." 

While the actual site disappeared after April 1, the archived version can be seen here.

X-Ray vision Nokia 9 PureView

UPDATE: Getting ready for go-live! pic.twitter.com/ijsAXz8QhG

— Juho Sarvikas (@sarvikas) April 1, 2019

The Nokia 9 PureView has plenty of cameras on its back, but did you know that the black sensor isn’t a 3D ToF camera but rather an X-Ray sensor? Can be unlocked with the new Nokia X-Ray app in Play Store


"Digi-U" from Ericsson Digital

We announce a new innovation from our @EricssonDigital team - a Digi-ize yourself app called: "Digi-U". This app is available for download to your smart phone and within 10 minutes you will have transformed yourself into a mini-me hologram.

For more: #HappyAprilFoolsDay :-) pic.twitter.com/iCDiU1lHhj

— Ericsson Digital (@EricssonDigital) April 1, 2019

Parallel Wireless Adds AMPS (1G) Capabilities to Their Unified ALL G Architecture

From the press release:

Worlds First Fully Virtualized AMPS (vAMPS) to enable Modernization and Cost Savings

Parallel Wireless vAMPS is compatible with: Total Access Communications Systems (TACS) in the U.K.; Nordic Mobile Telephone (NMT) System in Scandinavia; C450 in Germany; and NTT System in Japan, among others, and will allow global operators to modernize their 1G infrastructure. The 1G vAMPS solution is also software upgradable to vD-AMPS, for operators who wish to follow that path.

Truphone foldable SIM (F-SIM) for Foldable Smartphones

From Truphone website:

F-SIM – the foldable SIM – designed especially for the new foldable smartphones and tablets demonstrated at this February’s MWC Barcelona, including Huawei’s Mate X and Samsung’s Galaxy Fold.

Widely tipped as the next generation in SIM technology, the foldable SIM works on minute hinges that allow it to fold smaller than any previous SIM form factor. Made specifically for foldable phones and other devices, Truphone’s latest innovation fulfils on its broader brand promise to engineer better connections between things, people and business—anywhere in the world.

The F-SIM comes in ‘steel grey’ and, for only £5 more, ‘hot pink’. Pricing structures vary depending on data, storage, roaming charges and device model.


Google Screen Cleaner in the Files app




Mother of All USB-C Hubs for Apple Macbook - HyperDrive Ultimate Ultimate Hub

The Mother of All USB-C Hubs for Apple Macbook - HyperDrive Ultimate Hub with built-in battery, speaker, 3.5" floppy disk drive, parallel, serial, PS/2, AT ports & 40 other ports from @Hyper - https://t.co/KpbZflRDcY #AprilFoolsDay #AprilFools2019 #AprilFools pic.twitter.com/xLIGXLcr8G

— 3G4G (@3g4gUK) April 2, 2019

Other funny April Fools jokes:

• Captain Marvel Universal Pager
• Polite Car Horn from Honda Canada
• Duolingo Push
• Shutterstock Announces Plans to Build World’s Largest Brick-and-Mortar Library
• Parody Apple Ad: "The Sound Gardener"
• Audible for Fish
• Logitech Hamsters
• Nissin/HyperX Limited Edition Cup Noodle Headphones
• Roku Press Paws Remote for Pets
• OnePlus Warp Car - Los Angeles to Las Vegas on a single 20 minute charge
• Google Tulip: Decoding the language of flowers
• Introducing Waymo Pet - a self-driving service for pets
• Nvidia R.O.N.: The world's first AI powered virtual gaming assistant.

One of the funniest jokes is Qualcomm's HandSolo that was released back in 1998. You may enjoy watching here.

Related posts:

• Some interesting April Fools' Day 2018 Technology Jokes
• Some interesting April Fools' Day 2017 Technology Jokes
• Some interesting April Fools' Day 2016 Technology Jokes
• Some interesting April Fools' Day 2015 Technology Jokes
• Some interesting April Fools' Day 2014 Technology Jokes

5G and IoT Security Update from ETSI Security Week 2018

ETSI Security Week 2018 (link) was held at ETSI's Headquarters in Sophia Antipolis, South of France last week. It covered wide variety of topics including 5G, IoT, Cybersecurity, Middlebox, Distributed Ledger Technology (DLT), etc. As 5G and IoT is of interest to the readers of this blog, I am providing links to the presentations so anyone interested can check them out at leisure.

Before we look at the presentations, what exactly was the point of looking at 5G Security? Here is an explanation from ETSI:

5G phase 1 specifications are now done, and the world is preparing for the arrival of 5G networks. A major design goal of 5G is a high degree of flexibility to better cater for specific needs of actors from outside the telecom sector (e.g. automotive industry, mission-critical organisations). During this workshop, we will review how well 5G networks can provide security for different trust models, security policies, and deployment scenarios – not least for ongoing threats in the IoT world. 5G provides higher flexibility than legacy networks by network slicing and virtualization of functions. The workshop aims to discuss how network slicing could help in fulfilling needs for different users of 5G networks.

5G will allow the use of different authentication methods. This raises many interesting questions. How are these authentication methods supported in devices via the new secure element defined in ETSI SCP, or vendor-specific concepts? How can mission-critical and low-cost IoT use cases coexist side-by-side on the same network?

The 5G promise of higher flexibility is also delivered via its Service-Based Architecture (SBA). SBA provides open 3rd party interfaces to support new business models which allow direct impact on network functions. Another consequence of SBA is a paradigm shift for inter-operator networks: modern APIs will replace legacy signaling protocols between networks. What are the relevant security measures to protect the SBA and all parties involved? What is the role of international carrier networks like IPX in 5G?

Event Objectives
The workshop intends to:

• Gather different actors involved in the development of 5G, not only telecom, and discuss together how all their views have shaped phase 1 of 5G, to understand how security requirements were met, and what challenges remain;
• Discuss slicing as a means to implement separate security policies and compartments for independent tenants on the same infrastructure;
• Give an update of what is happening in 3GPP 5G security;
• Explain to IoT players what 5G security can (and cannot) do for them, including risks and opportunities related to alternative access credentials;
• Understand stakeholders' (PMNs, carriers, GSMA, vendors) needs to make SBA both secure and successful. How can SBA tackle existing issues in interconnect networks like fraud, tracking, privacy breaches;
• Allow vendors to present interesting proposals for open security questions in 5G: secure credential store, firewalling SBA's RESTful APIs;
• Debate about hot topics such as: IoT security, Slicing security, Privacy, Secure storage and processing and Security of the interconnection network.

So here are the relevant presentations:

Session 1: Input to 5G: Views from Different Stakeholders
Session Chair: Bengt Sahlin, Ericsson

Hardening a Mission Critical Service Using 5G, Peter Haigh, NCSC

Security in the Automotive Electronics Area, Alexios Lekidis, SecurityMatters

Integrating the SIM (iUICC), Adrian Escott, QUALCOMM

Smart Secure Platform, Klaus Vedder, Giesecke & Devrient, ETSI SCP Chairman

Network Slicing, Anne-Marie Praden, Gemalto

Don't build on Sand: Validating the Security Requirements of NFV Infrastructure to Confidently Run Slices, Nicolas Thomas, Fortinet

5G Enhancements to Non-3GPP Access Security, Andreas Kunz, Lenovo

Security and Privacy of IoT in 5G, Marcus Wong, Huawei Technologies

ITU-T activities and Action Plan on 5G Security, Yang Xiaoya, ITU-T SG17

Wrap up: 5G Overview from 3GPP SA3 Perspective and What is There to Be Done for Phase 2, Sander Kievit, TNO


Session 2: Security in 5G Inter-Network Signalling
Session Chair: Stefan Schroeder, T-Systems

Presentation on SBA: Introduction of the Topic and Current Status in SA3, Stefan Schroeder, T-Systems

5G Inter-PLMN Security: The Trade-off Between Security and the Existing IPX Business Model, Ewout Pronk, KPN on behalf of GSMA Diameter End to End Security Subgroup

Secure Interworking Between Networks in 5G Service Based Architecture, Silke Holtmanns, Nokia Bell Labs

Security Best Practises using RESTful APIs, Sven Walther, CA Technologies

Identifying and Managing the Issues around 5G Interconnect Security, Stephen Buck, Evolved Intelligence

Zero Trust Security Posture in 5G Architecture, Galina Pildush, Palo Alto Networks (Missing)


Session 1 & 2 Workshop Wrap up: 5G Phase 1 Conclusions and Outlook Towards Phase 2 - Stefan Schroeder, T-Systems and Bengt Sahlin, Ericsson


Session 5: Benefits and Challenges of 5G and IoT From a Security Perspective
Session Chair: Arthur van der Wees, Arthur's Legal

Setting the Scene, Franck Boissière, European Commission

ENISA's View on Security Implications of IoT and 5G, Apostolos Malatras, ENISA

Smart City Aspects, Bram Reinders, Institute for Future of Living

The Network Operators Perspective on IoT Security, Ian Smith, GSMA


Related Links:

• Detecting false base stations in mobile networks - Ericsson Research Blog
• 5G Security Updates - March 2018 - 3G4G Blog
• Introduction to 3GPP Security in Mobile Cellular Networks - 3G4G Blog

Mobile Telecoms Technology & Market Disruptions

Sometimes its good to take a step back and look at the new applications and services that are already happening or may be happening sometime soon. Some of these have a possibility to disrupt the existing industries and markets, giving rise to not only new players but a completely new order.

Embedded below is a presentation from Dean Bubley of Disruptive Analysis. While there are a few things that I look at differently, there are many interesting points that the industry should already be looking at.

A good example of disruption would be the SIM card evolution that Apple introduced in iPadAir2 and iPadMini3. While they had great expectations, it didnt work out exactly as they had hoped due to the operators not letting Apple use the feature they wanted. In fact John Legere, T-Mobile US CEO, took to twitter to explain the problem. See here.

Another example is the new MVNO model by Google (Fi) in the USA. The problem in USA compared to Europe is that the operators have monopoly in many areas (fixed and mobile) and they can also get away with charging far higher amounts.

In addition, the problem that the operators have is that they focus on areas where they don't have issues; crying wolf if required. An example is taking advantage of 'data tsunami' and using it to hoard spectrum, as be seen from the tweet below:

Verizon Wireless admits to hoarding spectrum, ends any argument about a spectrum crunch http://t.co/0aqpGxlEvm
— Kevin Ahoy (@FlightsimGeek) February 23, 2015

Anyway, here is the presentation. Let me know what you think.

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.

European Regulations for 'Decoupling of SIM' and 'International Roaming'

The following is an extract from an article from Capana:

From the 1st of July 2014, the new EU Roaming Regulations III will become active.

The new EU Roaming regulations set by the European Commission, will allow retail mobile customers to purchase roaming services (such as voice, SMS and data) from an Alternative Roaming Provider (ARP) separate from their domestic service provider (DSP), without affecting either mobile number or device.

The general idea behind the regulations is to promote the interests of European citizens by increase competition between European operators, provide greater transparency, reduce bill shocks, and ultimately provide a greater roaming experience and higher quality of service for consumers.

European Commission President Jose Manuel Barosso said in a press release:

“Further substantial progress towards a European single market for telecoms is essential for Europe’s strategic interests and economic progress. For the telecoms sector itself and for citizens who are frustrated that they do not have full and fair access to internet and mobile services.”

Vice President Neelie Kroes, the Digital Agenda Commissioner responsible for package then continued in the same press release by saying:

“The legislation proposed today is great news for the future of mobile and internet in Europe. The European Commission says no to roaming premiums, yes to net neutrality, yes to investment, yes to new jobs. Fixing the telecoms sector is no longer about this one sector but about supporting the sustainable development of all sectors.”

Requirements

The process of selecting an ARP and its services while abroad within EU is more commonly known as decoupling or separate sale of roaming services. BEREC (the body of European Regulators for Electronic Communications) have provided the European Commission with their recommendations of two decoupling models that should be supported; Local breakout (LBO, which is the local provisioning of data services by a visited network operator, or Single IMSI solution where the ARP acts as a reseller of the DSPs service offerings.

Decoupling using Single IMSI

With the Single IMSI solution the ARP will engage in agreements with each domestic operator providing domestic services, then the ARP will act as a reseller of these services to the roaming subscriber. This type of solution is applicable for all types of service providers such as mobile network operators, MVNOs or VSPs. From a subscriber standpoint, they will have a roaming agreement with the ARP regardless of the DSP and the DSP is required to activate services within one working day.

Decoupling using Local Breakout

The Local breakout model refers to local provisioning of data services only, where the services is provided directly on the visited network and traditional SMS and voice traffic is supplied by the home operator in traditional roaming manner. By using the 3GPP option for local breakouts, the VPMN will be able to act as ARP for internet access and other data services.

With these new regulatory changes, there is a higher demand on flexibility in billing systems. Support for more complex multi-partner business models for ARP and MVNO is necessary for both billing and financial settlement activities.

Raymond Bouwman from Rabion Consultancy did an excellent presentation last year in the LTE World Summit, here is his presentation explaining more about the EU Roaming Regulations III

The SIM and International Roaming - Decoupling of Roaming from Zahid Ghadialy

Multi-SIM: The Jargon

I had been having some discussions regarding Multi-SIM phones and there is a bit of misunderstanding so here is my clarification about them. Anyway, a lot of information is just an understanding so feel free to correct any mistakes you think I may have made.

This post is about multiple SIM cards, physical UICC cards rather than single UICC with multiple SIM applications. We will look at Dual IMSI later on in the post. In case you do not know about the multiple SIM applications in a UICC, see this old post here. In this post, I will refer to UICC cards as SIM cards to avoid confusion.

Back in the old days, the Dual-SIM phones allowed only one SIM on standby at any time. The other SIM was switched off. If someone would call the number that was switched off, a message saying that the number is switched off would come or it would go in the voicemail. To make this SIM in standby, you would have to select it from the Menu. The first SIM is now switched off. The way around it was to have one SIM card calls forwarded the other when switched off. This wasn't convenient and efficient, money wise. The reason people use multiple SIM phones is to have cheaper calls using different SIMs. So in this case forwarding calls from one SIM to another wont be cost effective. These type of phones were known as Dual SIM Single Standby or DSSS. These devices had a single transceiver.

So as the technology got cheaper and more power efficient, the new multi-SIM devices could incorporate two receivers but only one transmitter was used. The main reason being that using two transmitters would consume much more power. As a result, these devices can now have both the SIM's on standby at the same time. These kind of devices were known as Dual SIM Dual Standby or DSDS. Wikipedia also calls then Dual SIM Standby or DSS. This concept could be extended further to Triple SIM Triple Standby or TSTS in case of the device with three SIM cards and Quad SIM Quad Standby or QSQS in case of four SIM cards. One thing to remember is that when a call is received and a SIM becomes active, the other SIM cards become inactive for the duration of the call. A workaround for that situation is to forward the call to the other SIM card in case if its unavailable. Though this will work for DSDS, it may not be that straightforward in case of TSTS and QSQS due to more than two SIM cards being present.

Another category of devices that are now available are the Dual SIM Dual Active or DSDA. In this case there are two transceivers in the device. Both the SIM cards are active at the same time so each SIM card can handle the call independently of each other. It would even be possible to conference both these calls.

With the prices of calls falling, there is no longer a real need for multiple SIM cards. One SIM card is generally sufficient. It may be useful though to have multiple IMSI on the SIM card. The different IMSI would have different country and network code. For example, a person in in UK can have one IMSI with the home network code and one with say a US operator IMSI. This IMSI could only be programmed by the home operator. When the person is in UK he could receive calls on his UK number or on the US number which would be routed to his UK number. For a person in US calling the US number, this is a national call rather than an international one. When the person is roaming in the US, his US IMSI would behave like non-roaming case while the calls to the UK number would be forwarded to the US number.

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

2 Factor and 3 Factor Authentication (2FA / 3FA)

Found an interesting slide showing 2 Factor Authentication in picture from a presentation in LTE World Summit

You can also read more about this and Multi-factor Authentication (MFA) on Wikipedia here.

Connectivity in 'Connected Vehicles'

An interesting presentation from the Future of Wireless International conference about the evolution and options for connected cars and other vehicles

Connected Vehicle - Accenture from Zahid Ghadialy

M2M Standardization and its Role for Emerging Smart Cities

Interesting presentation from FOKUS Fuseco forum 2012.

Global M2M Standardization and its Role for Emerging Smart Cities from Zahid Ghadialy

Related presentation on slideshare here.

Fourth proposal for the nano-SIM Card (4FF)

I blogged about the nano-SIM card earlier and the 3 proposals that are causing the deadlock. Here is a new fourth proposal that has been submitted by RIM that is a compromise between the Apple and Nokia designs (see pic here). Proposal as seen below:

According to The Register:


At issue is the shape and size of the standard next-generation SIM: Apple and a band of network operators want a tray-requiring shape and contacts that would permit a convertor for backwards compatibility with chunkier old SIMs. Nokia, Motorola and RIM have pushed for a new contact pattern and a notched SIM for clunk-click, and tray-less, insertion.


The new proposal, apparently put forward by RIM and Motorola, is a compromise but it hasn't secured backing from either of the most-belligerent parties - yet. Copies of the design, as well as Moto's presentation in March that compared the competing interfaces, have been seen by the chaps at The Verge.


What all parties agree on is that a smaller SIM is needed: the first SIMs were the same size as credit cards (conforming to ISO7816), while the second form factor (2FF) is the SIM with which most of us are familiar (conforming to GSM 11.11). Next was the microSIM (3FF), popularised by Apple's adoption in the iPhone; the 3FF just trims off the excess plastic while maintaining the contact pattern.


The undecided 4FF standard (dubbed the nanoSIM) will be thinner as well as smaller, and almost certainly feature a different contact pattern to make that practical, although how different is part of the ongoing debate.


The Apple-backed 4FF proposal was for a contact-compatible SIM with smooth sides necessitating an insertion tray, while Nokia wanted the contacts shifted to the far end and a notch along the side for easy push-to-lock fitting. The new RIM-Moto proposal, if genuine, places the contacts in compatible locations while maintaining the Nokia notch, appeasing both parties or perhaps annoying them both equally.


There have been claims that Nokia is just trying to protect its patent income, fanned by Apple's offer to waive its own IP fees if its proposal were adopted. That's something of a red herring as Apple's hasn't much IP in this area and Nokia's patents cover much more than the physical shape of the SIM so its revenue is pretty much assured.


Not that Nokia has helped itself by threatening to deny patent licences if its own proposal isn't adopted, claiming that Apple's divergence from rules laid down by telecoms standards body ETSI relives Nokia of its FRAND commitment to licence its technology on a fair and reasonable basis.

A slidepack by RIM on the 4FF UICC is embedded below and available to download from slideshare:

4FF: The next generation UICC

View more presentations from Zahid Ghadialy

MIM: Machine Identity Module - M2M SIM

What is nano-SIM card

BBC reported that there is some dispute between Apple and Nokia/Rim for the next generation of SIM cards, 'nano-SIM'. You can read more about that here.

While looking for how the nano-SIM is different from other SIM cards I came across an interesting presentation from G&D. The above picture summarises the different types of SIM cards in use. The following is an extract from their whitepaper:


When the GSM network first appeared, mobile devices resembled bricks or even briefcases, and SIM cards were the size of credit cards. The subsequent miniaturization of the phones led to the standardization of smaller SIMs, the Plug-in SIM, and later the Mini-UICC also known as 3rd form factor (3FF). With the introduction of Apple’s iPad, the 3FF, or the Micro-SIM as it was then called, established itself widely in the market.

Nevertheless, the trend towards miniaturization of the SIM card is still not over. The latest form factor which is currently in discussion at ETSI (European Telecommunications Standards Institute) is the 4th form factor (4FF) or Nano-SIM. Measuring 12.3 x 8.8 mm, the Nano-SIM is about 30 percent smaller than the Micro-SIM. Even the thickness (0.7 mm) of the card has been reduced by about 15 percent – a tremendous technical challenge.

The Nano-SIM offers device manufacturers the crucial advantage of freeing up extra space for other mobile phone Nano-SIM The smallest SIM form factor on the market components such as additional memory or larger batteries. Popular smart phones in particular have to strike a balance between the need for components that are more powerful but bulkier and a slim design. The reduced volume of the 4FF gives manufacturers the opportunity to produce devices that are thinner and more appealing.


In case you were wandering the differences that are causing the disagreements, here are the differences between the formats:

UICC and ISIM (IMS SIM)

I have mentioned before that UICC is the physical card and 2G SIM/USIM/ISIM are applications on the UICC card. The IMS SIM holds data provided by the IMS Operator, generally the same operator that would provide USIM services that would allow to camp on the 3G or LTE network.

Private User Identity: This identifies the user uniquely with the IMS operator and is used when the user registers with the IMS network. This is used by the operator to check the subscription and which services the user can avail of.

Public User Identity: A user can have multiple public identities that can be used for different services. To avail a particular service, user has to register with the particular public identity that has been allowed for that service.

Security Keys: Security keys are used for authentication to the IMS Network.

Home Network Domain Name: This is the name of the entry point that the user uses to register. This makes sure that a users request is sent to the Home Network.

Access Rule Reference: This is used to store information about which personal identification number needs verification for accessing a particular application

Address of P-CSCF: If it is not possible do dynamically find the Proxy-Call Session Control Function then this address is helpful

Administrative Data: Some of this could be operator specific proprietary information

Gemalto presentation on Soft SIM

Will a Soft SIM Change Everything?

View more presentations from Zahid Ghadialy

Facebook onto a SIM using Class 2 SMS

I am sure you have already heard of Gemalto's (worlds largest SIM manufacturer and supplier) Facebook on the SIM announcement. The advantage of this approach is that 100% of the existing phones will be able to support facebook (if the operator supports the application on the SIM). This is a big step0 forward. The press release says:

Gemalto’s software development team has embedded the software application into the SIM. This ensures the Facebook application is compatible with 100% of SIM-compliant mobile phones.

The innovative solution provides mobile subscribers with simple and convenient access to core Facebook features such as friend requests, status updates, wall posts or messages. It also offers unique functions: people can sign up for this service and log in directly from the SIM application. Interactive Facebook messages pop-up on the phone’s screen so people can always share up-to-the-minute posts and events. One can also automatically search their SIM phonebook for other friends and send them requests.

Facebook for SIM is extremely easy to use and is available to everyone. No data contract or application download is needed, because the software is embedded in the SIM and it uses SMS technology. As a result, it works for prepaid as well as for pay-monthly customers. Following an initial limited free trial period, Facebook for SIM then operates on a subscription model via an unlimited pass for a given period of time.

“Facebook for SIM enables operators to leverage two of their main assets: the SMS to communicate with the web application and the SIM for application distribution to the masses,” added Philippe Vallée, Executive Vice President, Gemalto. “Over 200 million people already use Facebook on handsets and those are twice as active as non-mobile users . By providing anytime, anywhere availability to the social network, Gemalto delivers on the growing demand for mobile connectivity all over the world.”

An article on the Register had more details:

The SIM-based client isn't as pretty as its smartphone contemporaries – don't expect picture streams or sliding interfaces – but it was developed with the help of Facebook, and provides text-menu-based interaction with Facebook – including status updates, pokes and friend requests – to any GSM-compatible handset through the magic of the GSM SIM Toolkit and Class 2 SMS messages.

The SIM Toolkit is part of the GSM standard and thus supported on just about every GSM handset, from the dumbest PAYG talker to the latest iGear. It allows the SIM to present menu options to the user, collect responses, and pop up alerts when new data arrives, which is all that's necessary for a basic Facebook client.

Modern handsets also allow the SIM to make TCP/IP data connections, but Gemalto is eschewing that for Class 2 SMS to ensure compatibility with the most basic handsets, and networks.

Class 2 SMS messages are delivered direct to the SIM without the user being involved, so can update friends' status messages and deliver a poke or two. The application running on the SIM then prods the handset into alerting the user.

That user's own updates are sent over SMS too, following a status change or wall posting client pastes that into an SMS, which is sent silently on its way.

How, or if, the network operator charges for all those messages flying about isn't clear. Gemalto won't name operators yet but claims to be talking to one operator who reckons that Facebook is eating half its bandwidth, and another who's already working on SIM distribution strategies.

Not that a new SIM is necessarily required – SIMs are field upgradable, though few operators deploy them with sufficient empty space for an application like this and issuing replacement SIMs is probably easier from a marketing point of view.

You can also find some of these details here.

As I have been working on SMS for the last few weeks, I decided to dig a bit deep into what these Class 2 SMS are.

Classes identify the message's importance as well as the location where it should be stored. There are 4 message classes.

Class 0: Indicates that this message is to be displayed on the MS immediately and a message delivery report is to be sent back to the SC. The message does not have to be saved in the MS or on the SIM card (unless selected to do so by the mobile user).

Class 1: Indicates that this message is to be stored in the MS memory or the SIM card (depending on memory availability).

Class 2: This message class is Phase 2 specific and carries SIM card data. The SIM card data must be successfully transferred prior to sending acknowledgement to the SC. An error message will be sent to the SC if this transmission is not possible.

Class 3: Indicates that this message will be forwarded from the receiving entity to an external device. The delivery acknowledgement will be sent to the SC regardless of whether or not the message was forwarded to the external device.

You can also read this for more details on SMS message contents