What is changed after introducing with microSIM?

 Hello everybody, after a half month, finally our new blog pops up. Because of a lot of stuff to handle, I could not be here. Anyway, I decided to write something about SIM cards. Like I said from prior blogs our goal is share information with people with simply and useful practically so we will not go into detail and get your feedback with questions, suggestions.  So that, we can enhance our knowledge.

What is SIM?

SIM means Subscriber Identity Module. SIM card is smart card, it holds subscriber information like IMSI, MSISDN ,SMS server information and memory for contact info , sms . SIM card also keeps authentication parameters like Sres, Op/Opc, Ki etc .

The European Telecommunications Standards Institute (ETSI), which sets the standards for SIM cards, tells us that except for the size of the plastic around the chip, micro SIM cards are identical to the SIM cards we normally find in phones.

There are two type SIM cards;
The first basic families are SIM/USIM (for 2G and some 3G networks), the RUIMs (for CDMA networks) and UICCs (for 3G and LTE networks).

USIM:Universal SIM   RUIM: Removable User Identity Module  UICC: Universal Integrated Circuit Card

Why do I need to use SIM card?

SIM card is our ID in mobile phone network. To be able to get into this network we need authentication. So this very small smart card holds all authentication parameters. Regarding GSM technology it uses different type Authentication algorithms like Milenage in UMTS and Snow-3G in LTE.

SIM Card capacity:

Each product family is then defined by the size of the memory made available to the telecom operator. They are usually 64KB, 128KB, 256KB, 500KB, 700KB, etc.  But i did not see any SIM card in real World with capacity 700kb for gsm.

 Which phones are using microSim?

Lates phones are Samsung Galaxy S4, BlackBerry Q10, LG Optimus G LTE 4G, HTC One 4G, Sony Xperia Z, Motorola RAZR i and Nokia Lumia 520.

Why microsim?
I could not find a good answer for it because of vendor requests. Physical Size of chip in both SIM and MicroSim are same.  Maybe it is for preventing unlocking but it is cutting to new microSIM shape with some special tools. So this theory is not valid at least in Turkey. If someone knows the actual reason please enlighten me J

How can I program SIM card

First you have to find SIM card reader. Some of them are Orga and Gemalto. But do not forget you cannot find any tool that can reach the files where authentication parameters are storing.

 Does SIM have special applications on it?

We call it VAS; it stands for Value Added Services. A value-added service (VAS) is a telecommunications industry term for non-core services or, in short, all services beyond standard voice calls. It was SMS, MMS and such kind of basic things in the past. After changing customer expectations it is changed to more advanced applications like Push-To-Talk, Call conferencing, SMS auto reply, Weather information, voicemail and so on. Since VAS is not simple thing, I am planning to explain VAS in future.

 

Sources:

http://www.eservglobal.com/solutions/value-added-services

http://cellplan4u.com/store/product_info.php?products_id=41

http://apcmag.com/card-tricks-why-apple-put-a-microsim-into-the-ipad.htm

http://asia.cnet.com/whats-the-big-deal-about-the-microsim-62200148.htm

 

 

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LTE Security

Based mobile networks supporting a rapidly growing number of computationally powerful devices  such as  smartphones and tablets is changing the mobile security landscape and will fundamentally 
change the way we perceive and deal with mobile security. Mobile networks are becoming more

pervasive, more widely used, and more deeply connected to other network.

 

Devices and the core network are most heavily targeted parts of the mobile network.



Basicaly we can separate the security as for subscriber authentication and attacking to mobile to core devices.

Authentication procedures use very complex algorithms, personally it is not a big threat for mobile operators. By the way, we are starting with authentication very briefly

Authentication
   
Operators like Verizon in USA are using 3GPP  SNOW 3G Specification for Confidentiality and Integrity Algorithms UEA2 & UIA2, 128-EEA1 & 128-EIA1.
  
SIM means Subscriber Identity Module (SIM). All wireless mobile technologies have different type of SIM cards. For example,USIM is using in 3G Sim cards with Milenage Authentication. Before 3G, we were using A3 and A8 authentication algorithms. 

A3/A8 had some weakness, that enable attackers to break the encryption key in less than one second, breaching customer’s identity and allowing billing fraud and  putting telecom operators in a serious legal situation.

The older SIM cards are not compatible and may not be used in LTE.

Security the keys used are128 bits in LTE.

  
Important: Mobile Phone has to support SNOW 3G algorithm.

 Securing LTE Backhaul

 

Most attacks will be directed at the mobile core network, external sites, and subscriber data and devices, but they can also be more limited in scope and target a single eNB or a group of nearby eNBs (eNB identity spoofing and impersonation).Tampering, traffic hijacking, eavesdropping, DoS,compromised control data,unauthorized access,and loss of accountability of the control plane are the biggest threats to the core network.

To secure traffic,as an my personal opinions based on my researches an IPsec tunnel has to be established between the eNB,and the MME, SGW and O&M in the core network over the user,control and management plane, and terminated at a SEG (security gateways) that sits at the border of the trusted area.

REFERENCES
http://www.mcit.gov.sa/nr/rdonlyres/d762830c-fbe7-4b36-aafc-780cfbafc92c/0/paper36.pdf 
http://www.3gpp.org/ftp/Information/presentations/presentations_2011/2011_05_Bangalore/DZBangalore290511.pdf
http://support.verizonwireless.com/faqs/VZAccess/4g_sim_card.html
http://security.stackexchange.com/questions/21395/how-is-4g-lte-encrypted
http://www.etsi.org/index.php/services/security-algorithms/3gpp-algorithms
http://www.authentec.com/Products/EmbeddedSecurity/SemiconductorIP/3G4GLTECiphers.aspx
http://itmf.uga.edu/minutes/2011-03-03/verizon_presentation.pdf
http://www.embedded.com/electronics-products/electronic-product-reviews/ip-eda-products/4212398/Elliptic-launches-security-processing-engine-for-4G-wireless-markets
http://www.radio-electronics.com/info/cellulartelecomms/lte-long-term-evolution/lte-security-authentication.php
http://www.sciencedirect.com/science/article/pii/S0140366410003105
http://www.slideshare.net/aliirfan04/lte-security-overview
http://www.f5.com/pdf/white-papers/wireless-security-lte-networks-wp.pdf
http://internetandwebsecurity.blogspot.com/2010/10/radisys-introduces-carrier-grade-lte.html
http://www.tellabs.com/resources/papers/tlab_ipsec_wp.pdf

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