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VoLGA

VoLGA Forum logo

VoLGA Forum was formed in March 2009 by a group of companies in the wireless industry in an effort to define a set of specifications for enabling delivery of voice services over 3GPP Long Term Evolution (LTE) access networks based on the current 3GPP Generic Access Network (GAN) standard.

VoLGA is an acronym for Voice over LTE via Generic Access.

The VoLGA Forum's mission is to promote the widespread adoption of VoLGA technology. The group wants to enable mobile operators to deliver voice and messaging services over upcoming LTE radio access networks using the same core networks they use today to support voice services on 2G/GSM and 3G/UMTS radio access networks.

The forum members include Alcatel-Lucent, Deutsche Telekom, Huawei, HTC Corporation, LG Electronics, Motorola, Nortel, Sonus Networks, Samsung, Starent Networks, and ZTE.

Swedish telecom equipment vendor Ericsson was originally a member of the VoLGA Forum, but revoked their membership in December 2009.

The group has developed and published a set of open specifications. These can be used by vendors and operators of wireless communications systems and applications to develop and deploy interoperable solutions.

In December 2009, Deutsche Telekom announced it had completed the world's first voice call over LTE.[1]

References[edit]

External links[edit]

Circuit Switched Data (CSD)

In communications, Circuit Switched Data (CSD) is the original form of data transmission developed for the time-division multiple access (TDMA)-based mobile phone systems like Global System for Mobile Communications (GSM). After 2010 many telecommunication carriers dropped support for CSD, and CSD has been superseded by GPRS and EDGE (E-GPRS).

Technical[edit]

CSD uses a single radio time slot to deliver 9.6 kbit/s data transmission to the GSM network switching subsystem where it could be connected through the equivalent of a normal modem to the Public Switched Telephone Network (PSTN), allowing direct calls to any dial-up service. For backwards compatibility, the IS-95 standard also supports CDMA Circuit Switched Data. However, unlike TDMA, there are no time slots, and all CDMA radios can be active all the time to deliver up to 14.4 kbit/s data transmission speeds. With the evolution of CDMA to CDMA2000 and 1xRTT, the use of IS-95 CDMA Circuit Switched Data declined in favour of the faster data transmission speeds available with the newer technologies.

Prior to CSD, data transmission over mobile phone systems was done by using a modem, either built into the phone or attached to it. Such systems were limited by the quality of the audio signal to 2.4 kbit/s or less. With the introduction of digital transmission in TDMA-based systems like GSM, CSD provided almost direct access to the underlying digital signal, allowing for higher speeds. At the same time, the speech-oriented audio compression used in GSM actually meant that data rates using a traditional modem connected to the phone would have been even lower than with older analog systems.

A CSD call functions in a very similar way to a normal voice call in a GSM network. A single dedicated radio time slot is allocated between the phone and the base station. A dedicated "sub-time slot" (16 kbit/s) is allocated from the base station to the transcoder, and finally, another time slot (64 kbit/s) is allocated from the transcoder to the Mobile Switching Centre (MSC).

At the MSC, it is possible to use a modem to convert to an "analog" signal, though this will typically actually be encoded as a digital pulse-code modulation (PCM) signal when sent from the MSC. It is also possible to directly use the digital signal as an Integrated Services Digital Network (ISDN) data signal and feed it into the equivalent of a remote access server.

High Speed Circuit Switched Data (HSCSD), is an enhancement to Circuit Switched Data (CSD), the original data transmission mechanism of the GSM mobile phone system, four to six times faster than GSM, with data rates up to 57.6 kbit/s.

Channel allocation is done in circuit-switched mode, as with CSD. This contrasts with the more widely adopted GPRS. Higher speeds are achieved as a result of superior coding methods, and the ability to use multiple time slots to increase data throughput.

High Speed Circuit Switched Data (HSCSD)[edit]

HSCSD is a system based on CSD but designed to provide higher data rates by means of more efficient channel coding and/or multiple (up to 4) time slots. It requires the time slots being used to be fully reserved to a single user. A transfer rate of up to 57.6 kbit/s (i.e., 4 × 14.4 kbit/s) can be reached, or even 115 kbit/s if a network allows combining 8 slots instead of just 4. It is possible that either at the beginning of the call, or at some point during a call, it will not be possible for the user's full request to be satisfied since the network is often configured to allow normal voice calls to take precedence over additional time slots for HSCSD users.

An innovation in HSCSD is to allow different error correction methods to be used for data transfer. The original error correction used in GSM was designed to work at the limits of coverage and in the worst case that GSM will handle. This means that a large part of the GSM transmission capacity is taken up with error correction codes. HSCSD provides different levels of possible error correction which can be used according to the quality of the radio link. This means that in the best conditions 14.4 kbit/s can be put through a single time slot that under CSD would only carry 9.6 kbit/s, i.e. a 50% improvement in throughput.

The user is typically charged for HSCSD at a rate higher than a normal phone call (e.g., by the number of time slots allocated) for the total period of time that the user has a connection active. This makes HSCSD relatively expensive in many GSM networks and is one of the reasons that packet-switched General Packet Radio Service (GPRS), which typically has lower pricing (based on amount of data transferred rather than the duration of the connection), has become more common than HSCSD.

Apart from the fact that the full allocated bandwidth of the connection is available to the HSCSD user, HSCSD also has an advantage in GSM systems in terms of lower average radio interface latency than GPRS. This is because the user of an HSCSD connection does not have to wait for permission from the network to send a packet.

HSCSD is also an option in Enhanced Data Rates for GSM Evolution (EDGE) and Universal Mobile Telecommunications System (UMTS) systems where packet data transmission rates are much higher. In the UMTS system, the advantages of HSCSD over packet data are even lower since the UMTS radio interface has been specifically designed to support high bandwidth, low latency packet connections. This means that the primary reason to use HSCSD in this environment would be access to legacy dial up systems.

Related[edit]

GSM data transmission has advanced since the introduction of CSD:

See also[edit]

References[edit]

Subscriber Identity Module

A typical SIM card (mini-SIM)
A mini-SIM card next to its electrical contacts in a Nokia 6233
A TracFone Wireless SIM card has no distinctive carrier markings and is only marked as a "SIM CARD".

A subscriber identity module or subscriber identification module (SIM), widely known as a SIM card, is an integrated circuit that is intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). It is also possible to store contact information on many SIM cards. SIM cards are always used on GSM phones; for CDMA phones, they are only needed for newer LTE-capable handsets. SIM cards can also be used in satellite phones, smart watches, computers, or cameras.

The SIM circuit is part of the function of a universal integrated circuit card (UICC) physical smart card, which is usually made of PVC with embedded contacts and semiconductors. SIM cards are transferable between different mobile devices. The first UICC smart cards were the size of credit and bank cards; sizes were reduced several times over the years, usually keeping electrical contacts the same, so that a larger card could be cut down to a smaller size.

A SIM card contains its unique serial number (ICCID), international mobile subscriber identity (IMSI) number, security authentication and ciphering information, temporary information related to the local network, a list of the services the user has access to, and two passwords: a personal identification number (PIN) for ordinary use, and a personal unblocking code (PUC) for PIN unlocking.

History and procurement[edit]

The SIM was initially specified by the European Telecommunications Standards Institute in the specification with the number TS 11.11. This specification describes the physical and logical behaviour of the SIM. With the development of UMTS, the specification work was partially transferred to 3GPP. 3GPP is now responsible for the further development of applications like SIM (TS 51.011[1]) and USIM (TS 31.102[2]) and ETSI for the further development of the physical card UICC.

The first SIM card was developed in 1991 by Munich smart-card maker Giesecke & Devrient, who sold the first 300 SIM cards to the Finnish wireless network operator Radiolinja.[3][4]

Today, SIM cards are ubiquitous, allowing over 7 billion devices to connect to cellular networks around the world. According to the International Card Manufacturers Association (ICMA), there were 5.4 billion SIM cards manufactured globally in 2016 creating over $6.5 billion in revenue for traditional SIM card vendors.[5] The rise of cellular IoT and 5G networks is predicted to drive the growth of the addressable market for SIM card manufacturers to over 20 billion cellular devices by 2020.[6] The introduction of Embedded SIM (eSIM) and Remote SIM Provisioning (RSP) from the GSMA[7] may disrupt the traditional SIM card ecosystem with the entrance of new players specializing in "digital" SIM card provisioning and other value-added services for mobile network operators.

Design[edit]

SIM chip structure and packaging

There are three operating voltages for SIM cards: 5 V, 3 V and 1.8 V (ISO/IEC 7816-3 classes A, B and C, respectively). The operating voltage of the majority of SIM cards launched before 1998 was 5 V. SIM cards produced subsequently are compatible with 3 V and 5 V. Modern cards support 5 V, 3 V and 1.8 V.

4 by 4 mm silicon chip in a SIM card which has been peeled open. Note the thin gold bonding wires, and the regular, rectangular digital memory areas.

Modern SIM cards allow applications to load when the SIM is in use by the subscriber. These applications communicate with the handset or a server using SIM Application Toolkit, which was initially specified by 3GPP in TS 11.14. (There is an identical ETSI specification with different numbering.) ETSI and 3GPP maintain the SIM specifications. The main specifications are: ETSI TS 102 223, ETSI TS 102 241, ETSI TS 102 588, and ETSI TS 131 111. SIM toolkit applications were initially written in native code using proprietary APIs. To provide interoperability of the applications, ETSI chose Java Card.[citation needed]. Additional standard size and specifications of interest are maintained by GlobalPlatform.

Data[edit]

SIM cards store network-specific information used to authenticate and identify subscribers on the network. The most important of these are the ICCID, IMSI, Authentication Key (Ki), Local Area Identity (LAI) and Operator-Specific Emergency Number. The SIM also stores other carrier-specific data such as the SMSC (Short Message Service Center) number, Service Provider Name (SPN), Service Dialing Numbers (SDN), Advice-Of-Charge parameters and Value Added Service (VAS) applications. (Refer to GSM 11.11[8])

SIM cards can come in various data capacities, from 8 KB to at least 256 KB. All can store a maximum of 250 contacts on the SIM, but while the 32 KB has room for 33 Mobile Network Codes (MNCs) or network identifiers, the 64 KB version has room for 80 MNCs.[citation needed] This is used by network operators to store data on preferred networks, mostly used when the SIM is not in its home network but is roaming. The network operator that issued the SIM card can use this to have a phone connect to a preferred network that is more economic for the provider instead of having to pay the network operator that the phone 'saw' first. This does not mean that a phone containing this SIM card can connect to a maximum of only 33 or 80 networks, but it means that the SIM card issuer can specify only up to that number of preferred networks. If a SIM is outside these preferred networks it uses the first or best available network.

ICCID[edit]

ICCID is the identifier of the actual SIM card itself - i.e. an identifier for the SIM chip. Each SIM is internationally identified by its integrated circuit card identifier (ICCID). ICCIDs are stored in the SIM cards and are also engraved or printed on the SIM card body during a process called personalisation. The ICCID is defined by the ITU-T recommendation E.118 as the Primary Account Number.[9] Its layout is based on ISO/IEC 7812. According to E.118, the number is up to 22 digits long, including a single check digit calculated using the Luhn algorithm. However, the GSM Phase 1[10] defined the ICCID length as 10 octets (20 digits) with operator-specific structure.

The number is composed of the following subparts:

Issuer identification number (IIN)

Maximum of seven digits:

  • Major industry identifier (MII), 2 fixed digits, 89 for telecommunication purposes.
  • Country code, 1–3 digits, as defined by ITU-T recommendation E.164.
  • Issuer identifier, 1–4 digits.

Individual account identification

  • Individual account identification number. Its length is variable, but every number under one IIN has the same length.

Check digit

  • Single digit calculated from the other digits using the Luhn algorithm.

With the GSM Phase 1 specification using 10 octets into which ICCID is stored as packed BCD, the data field has room for 20 digits with hexadecimal digit "F" being used as filler when necessary.

In practice, this means that on GSM SIM cards there are 20-digit (19+1) and 19-digit (18+1) ICCIDs in use, depending upon the issuer. However, a single issuer always uses the same size for its ICCIDs.

To confuse matters more, SIM factories seem to have varying ways of delivering electronic copies of SIM personalization datasets. Some datasets are without the ICCID checksum digit, others are with the digit.

As required by E.118, the ITU-T updates a list of all current internationally assigned IIN codes in its Operational Bulletins twice a month (the last is No. 1160 from 15 November 2018).[11] ITU-T also publishes complete lists: as of November 2018 list issued on 15 November 2015 was current, having all issuer identifier numbers before 15 November 2015.[12]

International mobile subscriber identity (IMSI)[edit]

SIM cards are identified on their individual operator networks by a unique International Mobile Subscriber Identity (IMSI). Mobile network operators connect mobile phone calls and communicate with their market SIM cards using their IMSIs. The format is:

  • The first three digits represent the Mobile Country Code (MCC).
  • The next two or three digits represent the Mobile Network Code (MNC). Three-digit MNC codes are allowed by E.212 but are mainly used in the United States and Canada.
  • The next digits represent the mobile subscriber identification number (MSIN). Normally there are 10 digits, but can be fewer in the case of a 3-digit MNC or if national regulations indicate that the total length of the IMSI should be less than 15 digits.
  • Digits are different from country to country.

Authentication key (Ki)[edit]

The Ki is a 128-bit value used in authenticating the SIMs on a GSM mobile network (for USIM network, you still need Ki but other parameters are also needed). Each SIM holds a unique Ki assigned to it by the operator during the personalization process. The Ki is also stored in a database (termed authentication center or AuC) on the carrier's network.

The SIM card is designed to prevent someone from getting the Ki by using the smart-card interface. Instead, the SIM card provides a function, Run GSM Algorithm, that the phone uses to pass data to the SIM card to be signed with the Ki. This, by design, makes using the SIM card mandatory unless the Ki can be extracted from the SIM card, or the carrier is willing to reveal the Ki. In practice, the GSM cryptographic algorithm for computing SRES_2 (see step 4, below) from the Ki has certain vulnerabilities[13] that can allow the extraction of the Ki from a SIM card and the making of a duplicate SIM card.

Authentication process:

  1. When the mobile equipment starts up, it obtains the international mobile subscriber identity (IMSI) from the SIM card, and passes this to the mobile operator, requesting access and authentication. The mobile equipment may have to pass a PIN to the SIM card before the SIM card reveals this information.
  2. The operator network searches its database for the incoming IMSI and its associated Ki.
  3. The operator network then generates a random number (RAND, which is a nonce) and signs it with the Ki associated with the IMSI (and stored on the SIM card), computing another number, that is split into the Signed Response 1 (SRES_1, 32 bits) and the encryption key Kc (64 bits).
  4. The operator network then sends the RAND to the mobile equipment, which passes it to the SIM card. The SIM card signs it with its Ki, producing SRES_2 and Kc, which it gives to the mobile equipment. The mobile equipment passes SRES_2 on to the operator network.
  5. The operator network then compares its computed SRES_1 with the computed SRES_2 that the mobile equipment returned. If the two numbers match, the SIM is authenticated and the mobile equipment is granted access to the operator's network. Kc is used to encrypt all further communications between the mobile equipment and the network.

Location area identity[edit]

The SIM stores network state information, which is received from the Location Area Identity (LAI). Operator networks are divided into Location Areas, each having a unique LAI number. When the device changes locations, it stores the new LAI to the SIM and sends it back to the operator network with its new location. If the device is power cycled, it takes data off the SIM, and searches for the prior LAI.

SMS messages and contacts[edit]

Most SIM cards store a number of SMS messages and phone book contacts. It stores the contacts in simple "name and number" pairs. Entries that contain multiple phone numbers and additional phone numbers are usually not stored on the SIM card. When a user tries to copy such entries to a SIM, the handset's software breaks them into multiple entries, discarding information that is not a phone number. The number of contacts and messages stored depends on the SIM; early models stored as few as five messages and 20 contacts, while modern SIM cards can usually store over 250 contacts.[citation needed]

Formats[edit]

From left, full-size SIM (1FF), mini-SIM (2FF), micro-SIM (3FF), and nano-SIM (4FF)
Nano-SIM (in bottom), micro-SIM and mini-SIM, SIM brackets from Movistar in Colombia
The memory chip from a micro-SIM card without the plastic backing plate, next to a US dime, which is approx. 18 mm in diameter
Embedded SIM from M2M supplier Eseye with an adapter board for evaluation in a Mini-SIM socket

SIM cards have been made smaller over the years; functionality is independent of format. Full-size SIM were followed by mini-SIM, micro-SIM, and nano-SIM. SIM cards are also made to embed in devices.

SIM card formats and dimensions
SIM card format Introduced Standard reference Length (mm) Width (mm) Thickness (mm)
Full-size (1FF) 1991 ISO/IEC 7810:2003, ID-1 85.60 53.98 0.76
Mini-SIM (2FF) 1996 ISO/IEC 7810:2003, ID-000 25.00 15.00 0.76
Micro-SIM (3FF) 2003 ETSI TS 102 221 V9.0.0, Mini-UICC 15.00 12.00 0.76
Nano-SIM (4FF) early 2012 ETSI TS 102 221 V11.0.0 12.30 8.80 0.67
Embedded-SIM
(eSIM)
JEDEC Design Guide 4.8, SON-8
ETSI TS 103 383 V12.0.0
GSMA SGP.22 V1.0
6.00 5.00 <1.00

Full-size SIM[edit]

The full-size SIM (or 1FF, 1st form factor) was the first form factor to appear. It has the size of a credit card (85.60 mm × 53.98 mm × 0.76 mm). Later smaller SIMs are often supplied embedded in a full-size card from which they can be removed.

Mini-SIM[edit]

The mini-SIM (or 2FF) card has the same contact arrangement as the full-size SIM card and is normally supplied within a full-size card carrier, attached by a number of linking pieces. This arrangement (defined in ISO/IEC 7810 as ID-1/000) lets such a card be used in a device that requires a full-size card – or in a device that requires a mini-SIM card, after breaking the linking pieces. As the full-size SIM is no longer used, some suppliers refer to the mini-SIM as a "standard SIM" or "regular SIM".

Micro-SIM[edit]

The micro-SIM (or 3FF) card has the same thickness and contact arrangements, but reduced length and width as shown in the table above.[14]

The micro-SIM was introduced by the European Telecommunications Standards Institute (ETSI) along with SCP, 3GPP (UTRAN/GERAN), 3GPP2 (CDMA2000), ARIB, GSM Association (GSMA SCaG and GSMNA), GlobalPlatform, Liberty Alliance, and the Open Mobile Alliance (OMA) for the purpose of fitting into devices too small for a mini-SIM card.[15][16]

The form factor was mentioned in the December 1998 3GPP SMG9 UMTS Working Party, which is the standards-setting body for GSM SIM cards,[17] and the form factor was agreed upon in late 2003.[18]

The micro-SIM was designed for backward compatibility. The major issue for backward compatibility was the contact area of the chip. Retaining the same contact area makes the micro-SIM compatible with the prior, larger SIM readers through the use of plastic cutout surrounds. The SIM was also designed to run at the same speed (5 MHz) as the prior version. The same size and positions of pins resulted in numerous "How-to" tutorials and YouTube video with detailed instructions how to cut a mini-SIM card to micro-SIM size.[19]

The chairman of EP SCP, Dr. Klaus Vedder, said[18]

"ETSI has responded to a market need from ETSI customers, but additionally there is a strong desire not to invalidate, overnight, the existing interface, nor reduce the performance of the cards."

Micro-SIM cards were introduced by various mobile service providers for the launch of the original iPad, and later for smartphones, from April 2010. The iPhone 4 was the first smartphone to use a micro-SIM card in June 2010, followed by many others.

Nano-SIM[edit]

The nano-SIM (or 4FF) card was introduced on 11 October 2012, when mobile service providers in various countries started to supply it for phones that supported the format. The nano-SIM measures 12.3 × 8.8 × 0.67 mm and reduces the previous format to the contact area while maintaining the existing contact arrangements. A small rim of isolating material is left around the contact area to avoid short circuits with the socket. The nano-SIM is 0.67 mm thick, compared to the 0.76 mm of its predecessor. 4FF can be put into adapters for use with devices designed for 2FF or 3FF SIMs, and is made thinner for that purpose,[20] but many phone companies do not recommend this.[21][not in citation given]

The iPhone 5, released in September 2012, was the first device to use a nano-SIM card, followed by other handsets.

Security[edit]

In July 2013, Karsten Nohl, a security researcher from SRLabs, described[22][23] vulnerabilities in some SIM cards that supported DES, which, despite its age, is still used by some operators.[23] The attack could lead to the phone being remotely cloned or let someone steal payment credentials from the SIM.[23] Further details of the research were provided at BlackHat on July 31, 2013.[23][24]

In response, the International Telecommunication Union said that the development was "hugely significant" and that it would be contacting its members.[25]

In February 2015, it was reported by The Intercept that the NSA and GCHQ had stolen the encryption keys (Ki's) used by Gemalto (the manufacturer of 2 billion SIM cards annually), enabling these intelligence agencies to monitor voice and data communications without the knowledge or approval of cellular network providers or judicial oversight.[26] Having finished its investigation, Gemalto claimed that it has “reasonable grounds” to believe that the NSA and GCHQ carried out an operation to hack its network in 2010 and 2011, but says the number of possibly stolen keys would not have been massive.[27]

Developments[edit]

When GSM was already in use, the specifications were further developed and enhanced with functionality such as SMS and GPRS. These development steps are referred as releases by ETSI. Within these development cycles, the SIM specification was enhanced as well: new voltage classes, formats and files were introduced.

USIM[edit]

In GSM-only times, the SIM consisted of the hardware and the software. With the advent of UMTS this naming was split: the SIM was now an application and hence only software. The hardware part was called UICC. This split was necessary because UMTS introduced a new application, the universal subscriber identity module (USIM). The USIM brought, among other things, security improvements like the mutual authentication and longer encryption keys and an improved address book.

UICC[edit]

"SIM cards" in developed countries today are usually UICCs containing at least a SIM application and a USIM application. This configuration is necessary because older GSM only handsets are solely compatible with the SIM application and some UMTS security enhancements rely on the USIM application.

Other variants[edit]

On cdmaOne networks, the equivalent of the SIM card is the R-UIM and the equivalent of the SIM application is the CSIM.

A virtual SIM is a mobile phone number provided by a mobile network operator that does not require a SIM card to connect phone calls to a user's mobile phone.

Embedded-SIM[edit]

An Embedded-SIM (eSIM) or embedded universal integrated circuit card (eUICC) is a form of programmable SIM that is embedded directly into a device. The surface mount format provides the same electrical interface as the full size, 2FF and 3FF SIM cards, but is soldered to a circuit board as part of the manufacturing process. In M2M applications where there is no requirement to change the SIM card, this avoids the requirement for a connector, improving reliability and security. An eSIM can be provisioned remotely; end-users can add or remove operators without the need to physically swap a SIM from the device.[28]

The GSMA had been discussing the possibilities of a software-based SIM card since 2010.[29] While Motorola noted that eUICC is geared at industrial devices, Apple "disagreed that there is any statement forbidding the use of an embedded UICC in a consumer product." In 2012,[30] The European Commission has selected the Embedded UICC format for its in-vehicle emergency call service known as eCall. All new car models in the EU must have one by 2018 to instantly connect the car to the emergency services in case of an accident. Russia has a similar plan with the ERA-GLONASS regional satellite positioning system.[31] Singapore is seeking public opinions on introducing eSIM as a new standard as more compatible devices enter the market.[32]

Apple implemented e-SIM support in its Apple Watch series 3 and second generation iPad Pro devices.[33][34] In October 2017, Google unveiled the Pixel 2, which added e-SIM support for use with its Project Fi service.[35] The following year, Apple released the iPhone XS with e-SIM support.[36][37]

Usage in mobile phone standards[edit]

The use of SIM cards is mandatory in GSM devices.

The satellite phone networks Iridium, Thuraya and Inmarsat's BGAN also use SIM cards. Sometimes, these SIM cards work in regular GSM phones and also allow GSM customers to roam in satellite networks by using their own SIM card in a satellite phone.

Japan's 2G PDC system (which was shut down in 2012; SoftBank Mobile has already shut down PDC from March 31, 2010) also specifies a SIM, but this has never been implemented commercially. The specification of the interface between the Mobile Equipment and the SIM is given in the RCR STD-27 annex 4. The Subscriber Identity Module Expert Group was a committee of specialists assembled by the European Telecommunications Standards Institute (ETSI) to draw up the specifications (GSM 11.11) for interfacing between smart cards and mobile telephones. In 1994, the name SIMEG was changed to SMG9.

Japan's current and next generation cellular systems are based on W-CDMA (UMTS) and CDMA2000 and all use SIM cards. However, Japanese CDMA2000-based phones are locked to the R-UIM they are associated with and thus, the cards are not interchangeable with other Japanese CDMA2000 handsets (though they may be inserted into GSM/WCDMA handsets for roaming purposes outside Japan).

CDMA-based devices originally did not use a removable card, and the service for these phones bound to a unique identifier contained in the handset itself. This is most prevalent in operators in the Americas. The first publication of the TIA-820 standard (also known as 3GPP2 C.S0023) in 2000 defined the Removable User Identity Module (R-UIM). Card-based CDMA devices are most prevalent in Asia.

The equivalent of a SIM in UMTS is called the universal integrated circuit card (UICC), which runs a USIM application. The UICC is still colloquially called a SIM card.[citation needed]

SIM and carriers[edit]

The SIM card introduced a new and significant business opportunity for MVNOs – mobile virtual network operators – who lease capacity from one of the network operators rather than owning or operating a cellular telecoms network, and only provide a SIM card to their customers. MVNOs first appeared in Denmark, Hong Kong, Finland and the UK. Today they exist in over 50 countries, including most of Europe, United States, Canada, Mexico, Australia and parts of Asia, and account for approximately 10% of all mobile phone subscribers around the world.[citation needed]

On some networks, the mobile phone is locked to its carrier SIM card, meaning that the phone only works with SIM cards from the specific carrier. This is more common in markets where mobile phones are heavily subsidised by the carriers, and the business model depends on the customer staying with the service provider for a minimum term (typically 12, 18 or 24 months). SIM cards that are issued by providers with an associated contract are called SIM-only deals. Common examples are the GSM networks in the United States, Canada, Australia, the UK and Poland. Many businesses offer the ability to remove the SIM lock from a phone, effectively making it possible to then use the phone on any network by inserting a different SIM card. Mostly, GSM and 3G mobile handsets can easily be unlocked and used on any suitable network with any SIM card.

In countries where the phones are not subsidised, e.g., India, Israel and Belgium, all phones are unlocked. Where the phone is not locked to its SIM card, the users can easily switch networks by simply replacing the SIM card of one network with that of another while using only one phone. This is typical, for example, among users who may want to optimise their carrier's traffic by different tariffs to different friends on different networks, or when traveling internationally.

In 2016, carriers started using the concept of automatic SIM reactivation[38] whereby they let users reuse expired SIM cards instead of purchasing new ones when they wish to re-subscribe to that operator. This is particularly useful in countries where prepaid calls dominate and where competition drives high churn rates, as users had to return to a carrier shop to purchase a new SIM each time they wanted to churn back to an operator.

SIM-only[edit]

Commonly sold as a product by mobile telecommunications companies, "SIM-only" refers to a type of legally binding contract between a mobile network provider and a customer. The contract itself takes the form of a credit agreement and is subject to a credit check.

Within a SIM-only contract the mobile network provider supplies their customer with just one piece of hardware, a SIM card, which includes an agreed amount of network usage in exchange for a monthly payment. Network usage within a SIM-only contract can be measured in minutes, text, data or any combination of these. The duration of a SIM-only contract varies depending on the deal selected by the customer, but in the UK they are available over 1, 3, 6, and 12 month periods.

SIM-only contracts differ from mobile phone contracts in that they do not include any hardware other than a SIM card. In terms of network usage, SIM-only is typically more cost effective than other contracts because the provider does not charge more to offset the cost of a mobile device over the contract period. Short contract length is one of the key features of SIM-only – made possible by the absence of a mobile device.

SIM-only is increasing in popularity very quickly.[39] In 2010 pay monthly based mobile phone subscriptions grew from 41 percent to 49 percent of all UK mobile phone subscriptions.[40] According to German research company Gfk, 250,000 SIM-only mobile contracts were taken up in the UK during July 2012 alone, the highest figure since GfK began keeping records.

Increasing smartphone penetration combined with financial concerns are leading customers to save money by moving onto a SIM-only when their initial contract term is over.

Multiple-SIM devices[edit]

Devices with two SIM slots are known as dual SIMs. Dual-SIM mobile phones usually come with two slots for SIMs, one behind the battery and another on the side of the phone, though in some devices both slots can be found on the battery tray, or on the side of the phone if the device does not have a removable battery. Multiple-SIM devices are commonplace in developing markets such as in Africa, East Asia, the Indian subcontinent and Southeast Asia, where billing rates and variable network coverage/mode, make it desirable for consumers to use multiple SIMs from competing networks. It's also useful when you split work and home number for better privacy. They are not common in the Western world.

See also[edit]

References[edit]

  1. ^ "3GPP specification: 51.011". Retrieved 29 April 2016.
  2. ^ "3GPP specification: 31.102". Retrieved 29 April 2016.
  3. ^ Asif, Saad Z. (2011). Next Generation Mobile Communications Ecosystem. John Wiley & Sons. p. 306. ISBN 1119995817.
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  5. ^ "Official Publication of the International Card Manufacturers Association February 2017 Volume 27 No1" (PDF). Retrieved 28 May 2017.
  6. ^ "Ericsson Mobility Report November 2015" (PDF). Retrieved 28 May 2017.
  7. ^ "GSMA Embedded SIM and RSP". Retrieved 28 May 2017.
  8. ^ "3GPP specification: 11.11". Retrieved 29 April 2016.
  9. ^ ITU-T, ITU-T Recommendation E.118, The international telecommunication charge card, Revision history, Revision "05/2006"
  10. ^ ETSI, ETSI Recommendation GSM 11.11, Specifications of the SIM-ME Interface, Version 3.16.0
  11. ^ "Operational Bulletin No. 1160 (15.XI.2018)". www.itu.int. Retrieved 2018-11-14.
  12. ^ "Operational Bulletin No. 1088 (15.XI.2015) and Annexed List: List of issuer identifier numbers for the international telecommunication charge card (In accordance with Recommendation ITU-T E.118 (05/2006)) (Position on 15 November 2015)". International Telecommunication Union. 14 November 2015.
  13. ^ "Hackers crack open mobile network". bbc.co.uk. 20 April 2011. Retrieved 13 August 2011.
  14. ^ "What is a microsim card?". SimOnlyPro.nl. Archived from the original on 22 February 2013. Retrieved 14 October 2012.
  15. ^ Gaby Lenhart (1 April 2006). "The Smart Card Platform". ETSI Technical Committee Smart Card Platform (TB SCP). Retrieved 30 January 2010. SCP is co-operating on both technical and service aspects with a number of other committees both within and outside the telecommunications sector.
  16. ^ Segan, Sascha (27 January 2010). "Inside the iPad Lurks the 'Micro SIM'". PC Magazine. Retrieved 30 January 2010.
  17. ^ "DRAFT Report of the SMG9 UMTS Working Party, meeting #7 hosted by Nokia in Copenhagen, 15–16 December 1998" (PDF). 3GPP. 25 January 1999. Retrieved 27 January 2010. One manufacturer stated that it may be difficult to meeting ISO mechanical standards for a combined ID-1/micro-SIM card.
  18. ^ a b Antipolis, Sophia (8 December 2003). "New form factor for smart cards introduced". SmartCard Trends. Archived from the original on April 26, 2010. Retrieved 30 January 2010. The work item for the so-called Third Form Factor, "3FF", was agreed, after intensive discussions, at the SCP meeting held last week in London.
  19. ^ How to make MicroSIM on YouTube
  20. ^ Dr. Klaus Vedder (18 January 2012). "The UICC – Recent Work of ETSI TC Smart Card Platform" (PDF). ETSI. p. 12. Retrieved 22 July 2012.
  21. ^ Virgin Mobile. "An important guide to inserting your SIM into your mobile" (PDF). Retrieved 21 January 2017.
  22. ^ Encryption Bug in SIM Card Can be Used to Hack Millions of Phones, published 2013-07-21, accessed 2013-07-22
  23. ^ a b c d Rooting SIM cards, SR Labs, accessed 2013-07-22
  24. ^ "Black Hat USA 2013". Retrieved 29 April 2016.
  25. ^ UPDATE 1-UN warns on mobile cybersecurity bugs in bid to prevent attacks, Reuters, 2013-07-21, accessed 2013-07-21
  26. ^ "The Great SIM Heist - How Spies Stole the Keys to the Encryption Castle". The Intercept. The Intercept (First Look Media). February 19, 2015. Retrieved February 19, 2015.
  27. ^ "Gemalto: NSA/GCHQ Hack 'Probably Happened' But Didn't Include Mass SIM Key Theft". techcrunch.com. February 25, 2015. Retrieved April 2, 2015.
  28. ^ "eUICC – The Future for SIM Technology". PodM2M.
  29. ^ Diana ben-Aaron (18 November 2010). "GSMA Explores Software-Based Replacement for Mobile SIM Cards". Bloomberg. p. 1. Retrieved 17 October 2014.
  30. ^ Ziegler, Chris (June 1, 2012). "Embedded SIMs: they're happening, and Apple thinks they could be in consumer products". The Verge. Vox Media. Retrieved October 25, 2014.
  31. ^ Bruno, Duarte (September 27, 2014). "eUICC – embedded Universal Integrated Circuit Card". COSWITCHED.COM. Retrieved October 25, 2014.
  32. ^ https://www.channelnewsasia.com/news/singapore/switch-mobile-operator-without-changing-sim-cards-imda-wants-10395682
  33. ^ Evans, Jonny. "Apple Watch Series 4: A review". Computerworld. Retrieved 2018-11-09.
  34. ^ Martin, Jim. "Until now, all iPhones have been single SIM, but with eSIM you can have two phone numbers". Macworld UK. Retrieved 2018-11-09.
  35. ^ "Google's Pixel 2 phones are the first to use built-in eSIM technology". The Verge. Retrieved 2018-11-09.
  36. ^ "Apple brings dual-SIM support to the iPhone XS and XS Max". CNET. 2018-09-12. Retrieved 2018-11-09.
  37. ^ Cipriani, Jason. "What you need to know about the iPhone's new dual-sim feature". ZDNet. Retrieved 2018-11-09.
  38. ^ "Gemalto pioneers SIM reactivation". Retrieved 2016-11-03.
  39. ^ "A nation addicted to smartphones". Ofcom.
  40. ^ "UK sales of SIM-only mobile contracts set a new record". The Fone Cast. Retrieved 29 October 2012.

External links[edit]

Mobile phone

Evolution of mobile phones, to an early smartphone

A mobile phone, known as a cell phone in North America or hand phone in Asian English, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture, and, therefore, mobile telephones are called cellular telephones or cell phones, in North America. In addition to telephony, 2000s-era mobile phones support a variety of other services, such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, video games, and digital photography. Mobile phones offering only those capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones.

The first handheld mobile phone was demonstrated by John F. Mitchell[1][2] and Martin Cooper of Motorola in 1973, using a handset weighing c. 2 kilograms (4.4 lbs).[3] In 1979, Nippon Telegraph and Telephone (NTT) launched the world's first cellular network in Japan.[4] In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion--enough to provide one for every person on Earth.[5] In first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple, and Huawei, with smartphone sales represented 78 percent of total mobile phone sales.[6] For feature phones (or "dumbphones") as of 2016, the largest were Samsung, Nokia, and Alcatel.[7]

History

Martin Cooper of Motorola made the first publicized handheld mobile phone call on a prototype DynaTAC model on 3 April 1973. This is a reenactment in 2007.

A handheld mobile radio telephone service was envisioned in the early stages of radio engineering. In 1917, Finnish inventor Eric Tigerstedt filed a patent for a "pocket-size folding telephone with a very thin carbon microphone". Early predecessors of cellular phones included analog radio communications from ships and trains. The race to create truly portable telephone devices began after World War II, with developments taking place in many countries. The advances in mobile telephony have been traced in successive "generations", starting with the early zeroth-generation (0G) services, such as Bell System's Mobile Telephone Service and its successor, the Improved Mobile Telephone Service. These 0G systems were not cellular, supported few simultaneous calls, and were very expensive.

The Motorola DynaTAC 8000X. First commercially available handheld cellular mobile phone, 1984.

The first handheld cellular mobile phone was demonstrated by John F. Mitchell[1][2] and Martin Cooper of Motorola in 1973, using a handset weighing 2 kilograms (4.4 lb).[3] The first commercial automated cellular network (1G) analog was launched in Japan by Nippon Telegraph and Telephone in 1979. This was followed in 1981 by the simultaneous launch of the Nordic Mobile Telephone (NMT) system in Denmark, Finland, Norway, and Sweden.[8] Several other countries then followed in the early to mid-1980s. These first-generation (1G) systems could support far more simultaneous calls but still used analog cellular technology. In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone.

In 1991, the second-generation (2G) digital cellular technology was launched in Finland by Radiolinja on the GSM standard. This sparked competition in the sector as the new operators challenged the incumbent 1G network operators.

Ten years later, in 2001, the third generation (3G) was launched in Japan by NTT DoCoMo on the WCDMA standard.[9] This was followed by 3.5G, 3G+ or turbo 3G enhancements based on the high-speed packet access (HSPA) family, allowing UMTS networks to have higher data transfer speeds and capacity.

By 2009, it had become clear that, at some point, 3G networks would be overwhelmed by the growth of bandwidth-intensive applications, such as streaming media.[10] Consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3G technologies. The first two commercially available technologies billed as 4G were the WiMAX standard, offered in North America by Sprint, and the LTE standard, first offered in Scandinavia by TeliaSonera.

5G is a technology and term used in research papers and projects to denote the next major phase in mobile telecommunication standards beyond the 4G/IMT-Advanced standards. The term 5G is not officially used in any specification or official document yet made public by telecommunication companies or standardization bodies such as 3GPP, WiMAX Forum or ITU-R. New standards beyond 4G are currently being developed by standardization bodies, but they are at this time seen as under the 4G umbrella, not for a new mobile generation.

Types

Smartphone

Active mobile broadband subscriptions per 100 inhabitants.[11]

Smartphones have a number of distinguishing features. The International Telecommunication Union measures those with Internet connection, which it calls Active Mobile-Broadband subscriptions (which includes tablets, etc.). In the developed world, smartphones have now overtaken the usage of earlier mobile systems. However, in the developing world, they account for around 50% of mobile telephony.

Feature phone

Feature phone is a term typically used as a retronym to describe mobile phones which are limited in capabilities in contrast to a modern smartphone. Feature phones typically provide voice calling and text messaging functionality, in addition to basic multimedia and Internet capabilities, and other services offered by the user's wireless service provider. A feature phone has additional functions over and above a basic mobile phone which is only capable of voice calling and text messaging.[12][13] Feature phones and basic mobile phones tend to use a proprietary, custom-designed software and user interface. By contrast, smartphones generally use a mobile operating system that often shares common traits across devices.

Kosher phone

There are Orthodox Jewish religious restrictions which, by some interpretations, standard mobile telephones overstep. To deal with this problem, some rabbinical organizations have recommended that phones with text-messaging capability not be used by children.[14] Phones with restricted features are known as kosher phones and have rabbinical approval for use in Israel and elsewhere by observant Orthodox Jews. Although these phones are intended to prevent immodesty, some vendors report good sales to adults who prefer the simplicity of the devices. Some phones are approved for use by essential workers (such as health, security, and public service workers) on the sabbath, even though the use of any electrical device is generally prohibited during this time.[15]

Infrastructure

Mobile phones communicate with cell towers that are placed to give coverage across a telephone service area which is divided up into 'cells'. Each cell uses a different set of frequencies from neighbouring cells, and will typically be covered by 3 towers placed at different locations. The cell towers are usually interconnected to each other and the phone network and the internet by wired connections. Due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once. The cells are therefore sized depending on the expected usage density, and may be much smaller in cities. In that case much lower transmitter powers are used to avoid broadcasting beyond the cell.

As a phone moves around, a phone will "hand off"- automatically disconnect and reconnect to the tower that gives the best reception.

Additionally, short-range Wi-Fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks.

Hardware

The common components found on all phones are:

  • A CPU, the processor of phones.
  • A battery, providing the power source for the phone functions.
  • An input mechanism to allow the user to interact with the phone. These are a keypad for feature phones and touch screens for most smartphones.
  • A display which echoes the user's typing, and displays text messages, contacts, and more.
  • Speakers for sound.
  • SIM cards and R-UIM cards.

Low-end mobile phones are often referred to as feature phones and offer basic telephony. Handsets with more advanced computing ability through the use of native software applications are known as smartphones.

Central processing unit

Mobile phones have central processing units (CPUs), similar to those in computers, but optimised to operate in low power environments.

Mobile CPU performance depends not only on the clock rate (generally given in multiples of hertz)[16] but also the memory hierarchy also greatly affects overall performance. Because of these problems, the performance of mobile phone CPUs is often more appropriately given by scores derived from various standardized tests to measure the real effective performance in commonly used applications.

Display

One of the main characteristics of phones is the screen. Depending on the device's type and design, the screen fills most or nearly all of the space on a device's front surface. Many smartphone displays have an aspect ratio of 16:9, but taller aspect ratios became more common in 2017.

Screen sizes are measured in diagonal inches; feature phones generally have screen sizes below 3.5 inches. Phones with screens larger than 5.2 inches are often called "phablets." Smartphones with screens over 4.5 inches in size are commonly difficult to use with only a single hand, since most thumbs cannot reach the entire screen surface; they may need to be shifted around in the hand, held in one hand and manipulated by the other, or used in place with both hands. Due to design advances, some modern smartphones with large screen sizes and "edge-to-edge" designs have compact builds that improve their ergonomics, while the shift to taller aspect ratios have resulted in phones that have larger screen sizes whilst maintaining the ergonomics associated with smaller 16:9 displays.[17][18][19]

Liquid-crystal displays are the most common; others are IPS, LED, OLED, and AMOLED displays. Some displays are integrated with pressure-sensitive digitizers, such as those developed by Wacom and Samsung,[20] and Apple's "3D Touch" system.

Sound

In sound, smartphones and feature phones vary little. Some audio-quality enhancing features, such as Voice over LTE and HD Voice, have appeared and are often available on newer smartphones. Sound quality can remain a problem due to the design of the phone, the quality of the cellular network and compression algorithms used in long distance calls.[21][22] Audio quality can be improved using a VoIP application over WiFi.[23] Cellphones have small speakers so that the user can use a speakerphone feature and talk to a person on the phone without holding it to their ear. The small speakers can also be used to listen to digital audio files of music or speech or watch videos with an audio component, without holding the phone close to the ear.

Battery

The average phone battery lasts 2-3 years at best. Many of the wireless devices use a Lithium-Ion (Li-Ion) battery, which charges 500-2500 times, depending on how users take care of the battery and the charging techniques used.[24] It is only natural for these rechargeable batteries to chemically age, which is why the performance of the battery when used for a year or two will begin to deteriorate. Battery life can be extended by draining it regularly, not overcharging it, and keeping it away from heat.[25][26]

SIM card

Typical mobile phone mini-SIM card.

Mobile phones require a small microchip called a Subscriber Identity Module or SIM card, in order to function. The SIM card is approximately the size of a small postage stamp and is usually placed underneath the battery in the rear of the unit. The SIM securely stores the service-subscriber key (IMSI) and the Ki used to identify and authenticate the user of the mobile phone. The SIM card allows users to change phones by simply removing the SIM card from one mobile phone and inserting it into another mobile phone or broadband telephony device, provided that this is not prevented by a SIM lock. The first SIM card was made in 1991 by Munich smart card maker Giesecke & Devrient for the Finnish wireless network operator Radiolinja.[citation needed]

A hybrid mobile phone can hold up to four SIM cards, with a phone having an IMEI per SIM Card. SIM and R-UIM cards may be mixed together to allow both GSM and CDMA networks to be accessed. From 2010 onwards, such phones became popular in emerging markets,[27] and this was attributed to the desire to obtain the lowest on-net calling rate.

Software

Software platforms

Feature phones have basic software platforms.

Smartphones have advanced software platforms.

Mobile app

A mobile app is a computer program designed to run on a mobile device, such as a smartphone. The term "app" is a shortening of the term "software application".

Messaging
A text message (SMS).

A common data application on mobile phones is Short Message Service (SMS) text messaging. The first SMS message was sent from a computer to a mobile phone in 1992 in the UK while the first person-to-person SMS from phone to phone was sent in Finland in 1993. The first mobile news service, delivered via SMS, was launched in Finland in 2000,[citation needed] and subsequently many organizations provided "on-demand" and "instant" news services by SMS. Multimedia Messaging Service (MMS) was introduced in 2001.[citation needed]

Application stores

The introduction of Apple's App Store for the iPhone and iPod Touch in July 2008 popularized manufacturer-hosted online distribution for third-party applications (software and computer programs) focused on a single platform. There are a huge variety of apps, including video games, music products and business tools. Up until that point, smartphone application distribution depended on third-party sources providing applications for multiple platforms, such as GetJar, Handango, Handmark, and PocketGear. Following the success of the App Store, other smartphone manufacturers launched application stores, such as Google's Android Market (later renamed to the Google Play Store) and RIM's BlackBerry App World and Android-related app stores like F-Droid. In February 2014, 93% of mobile developers were targeting smartphones first for mobile app development.[28]

Sales

By manufacturer

Market share of top-five worldwide mobile phone vendors, Q2 2016
Rank Manufacturer Strategy
Analytics
report[29]
1 Samsung 22.3%
2 Apple 12.9%
3 Huawei 8.9%
4 Oppo 5.4%
5 Xiaomi 4.5%
Others 46.0%
Note: Vendor shipments are
branded shipments and exclude
OEM sales for all vendors

From 1983 to 1998, Motorola was market leader in mobile phones. Nokia was the market leader in mobile phones from 1998 to 2012.[30] In Q1 2012, Samsung surpassed Nokia, selling 93.5 million units as against Nokia's 82.7 million units. Samsung has retained its top position since then. In 2017, the top five manufacturers worldwide were Samsung (20.9%), Apple (14.0%), Huawei (9.8%), Oppo (5.7%), and Vivo (6.5%).[31] During Q2 2018, Huawei overtook Apple as the world's second-largest phone manufacturer.[32]

By mobile phone operator

Growth in mobile phone subscribers per country from 1980 to 2009.

The world's largest individual mobile operator by number of subscribers is China Mobile, which has over 902 million mobile phone subscribers as of June 2018.[33] Over 50 mobile operators have over ten million subscribers each, and over 150 mobile operators had at least one million subscribers by the end of 2009.[34] In 2014, there were more than seven billion mobile phone subscribers worldwide, a number that is expected to keep growing.

Use

General

Mobile phone subscribers per 100 inhabitants. 2014 figure is estimated.

Mobile phones are used for a variety of purposes, such as keeping in touch with family members, for conducting business, and in order to have access to a telephone in the event of an emergency. Some people carry more than one mobile phone for different purposes, such as for business and personal use. Multiple SIM cards may be used to take advantage of the benefits of different calling plans. For example, a particular plan might provide for cheaper local calls, long-distance calls, international calls, or roaming.

The mobile phone has been used in a variety of diverse contexts in society. For example:

  • A study by Motorola found that one in ten mobile phone subscribers have a second phone that is often kept secret from other family members. These phones may be used to engage in such activities as extramarital affairs or clandestine business dealings.[35]
  • Some organizations assist victims of domestic violence by providing mobile phones for use in emergencies. These are often refurbished phones.[36]
  • The advent of widespread text-messaging has resulted in the cell phone novel, the first literary genre to emerge from the cellular age, via text messaging to a website that collects the novels as a whole.[37]
  • Mobile telephony also facilitates activism and public journalism being explored by Reuters and Yahoo![38] and small independent news companies such as Jasmine News in Sri Lanka.[citation needed]
  • The United Nations reported that mobile phones have spread faster than any other form of technology and can improve the livelihood of the poorest people in developing countries, by providing access to information in places where landlines or the Internet are not available, especially in the least developed countries. Use of mobile phones also spawns a wealth of micro-enterprises, by providing such work as selling airtime on the streets and repairing or refurbishing handsets.[39]
  • In Mali and other African countries, people used to travel from village to village to let friends and relatives know about weddings, births, and other events. This can now be avoided in areas with mobile phone coverage, which are usually more extensive than areas with just land-line penetration.
  • The TV industry has recently started using mobile phones to drive live TV viewing through mobile apps, advertising, social TV, and mobile TV.[40] It is estimated that 86% of Americans use their mobile phone while watching TV.
  • In some parts of the world, mobile phone sharing is common. Cell phone sharing is prevalent in urban India, as families and groups of friends often share one or more mobile phones among their members. There are obvious economic benefits, but often familial customs and traditional gender roles play a part.[41] It is common for a village to have access to only one mobile phone, perhaps owned by a teacher or missionary, which is available to all members of the village for necessary calls.[42]

Content distribution

In 1998, one of the first examples of distributing and selling media content through the mobile phone was the sale of ringtones by Radiolinja in Finland. Soon afterwards, other media content appeared, such as news, video games, jokes, horoscopes, TV content and advertising. Most early content for mobile phones tended to be copies of legacy media, such as banner advertisements or TV news highlight video clips. Recently, unique content for mobile phones has been emerging, from ringtones and ringback tones to mobisodes, video content that has been produced exclusively for mobile phones.

Mobile banking and payment

Mobile payment system.

In many countries, mobile phones are used to provide mobile banking services, which may include the ability to transfer cash payments by secure SMS text message. Kenya's M-PESA mobile banking service, for example, allows customers of the mobile phone operator Safaricom to hold cash balances which are recorded on their SIM cards. Cash can be deposited or withdrawn from M-PESA accounts at Safaricom retail outlets located throughout the country and can be transferred electronically from person to person and used to pay bills to companies.

Branchless banking has also been successful in South Africa and the Philippines. A pilot project in Bali was launched in 2011 by the International Finance Corporation and an Indonesian bank, Bank Mandiri.[43]

Another application of mobile banking technology is Zidisha, a US-based nonprofit micro-lending platform that allows residents of developing countries to raise small business loans from Web users worldwide. Zidisha uses mobile banking for loan disbursements and repayments, transferring funds from lenders in the United States to borrowers in rural Africa who have mobile phones and can use the Internet.[44]

Mobile payments were first trialled in Finland in 1998 when two Coca-Cola vending machines in Espoo were enabled to work with SMS payments. Eventually, the idea spread and in 1999, the Philippines launched the country's first commercial mobile payments systems with mobile operators Globe and Smart.

Some mobile phones can make mobile payments via direct mobile billing schemes, or through contactless payments if the phone and the point of sale support near field communication (NFC).[45] Enabling contactless payments through NFC-equipped mobile phones requires the co-operation of manufacturers, network operators, and retail merchants.[46][47][48]

Mobile tracking

Mobile phones are commonly used to collect location data. While the phone is turned on, the geographical location of a mobile phone can be determined easily (whether it is being used or not) using a technique known as multilateration to calculate the differences in time for a signal to travel from the mobile phone to each of several cell towers near the owner of the phone.[49][50]

The movements of a mobile phone user can be tracked by their service provider and if desired, by law enforcement agencies and their governments. Both the SIM card and the handset can be tracked.[49]

China has proposed using this technology to track the commuting patterns of Beijing city residents.[51] In the UK and US, law enforcement and intelligence services use mobile phones to perform surveillance operations. They possess technology that enables them to activate the microphones in mobile phones remotely in order to listen to conversations which take place near the phone.[52][53]

Hackers are able to track a phone's location, read messages, and record calls, just by knowing the phone number.[54]

While driving

A driver using two hand-held mobile phones at once.
A sign in the U.S. restricting cell phone use to certain times of day

Mobile phone use while driving, including talking on the phone, texting, or operating other phone features, is common but controversial. It is widely considered dangerous due to distracted driving. Being distracted while operating a motor vehicle has been shown to increase the risk of accidents. In September 2010, the US National Highway Traffic Safety Administration (NHTSA) reported that 995 people were killed by drivers distracted by cell phones. In March 2011, a U.S. insurance company, State Farm Insurance, announced the results of a study which showed 19% of drivers surveyed accessed the Internet on a smartphone while driving.[55] Many jurisdictions prohibit the use of mobile phones while driving. In Egypt, Israel, Japan, Portugal, and Singapore, both handheld and hands-free use of a mobile phone (which uses a speakerphone) is banned. In other countries, including the UK and France and in many U.S. states, only handheld phone use is banned while hands-free use is permitted.

A 2011 study reported that over 90% of college students surveyed text (initiate, reply or read) while driving.[56] The scientific literature on the dangers of driving while sending a text message from a mobile phone, or texting while driving, is limited. A simulation study at the University of Utah found a sixfold increase in distraction-related accidents when texting.[57]

Due to the increasing complexity of mobile phones, they are often more like mobile computers in their available uses. This has introduced additional difficulties for law enforcement officials when attempting to distinguish one usage from another in drivers using their devices. This is more apparent in countries which ban both handheld and hands-free usage, rather than those which ban handheld use only, as officials cannot easily tell which function of the mobile phone is being used simply by looking at the driver. This can lead to drivers being stopped for using their device illegally for a phone call when, in fact, they were using the device legally, for example, when using the phone's incorporated controls for car stereo, GPS or satnav.

A 2010 study reviewed the incidence of mobile phone use while cycling and its effects on behaviour and safety.[58] In 2013, a national survey in the US reported the number of drivers who reported using their cellphones to access the Internet while driving had risen to nearly one of four.[59] A study conducted by the University of Vienna examined approaches for reducing inappropriate and problematic use of mobile phones, such as using mobile phones while driving.[60]

Accidents involving a driver being distracted by talking on a mobile phone have begun to be prosecuted as negligence similar to speeding. In the United Kingdom, from 27 February 2007, motorists who are caught using a hand-held mobile phone while driving will have three penalty points added to their license in addition to the fine of £60.[61] This increase was introduced to try to stem the increase in drivers ignoring the law.[62] Japan prohibits all mobile phone use while driving, including use of hands-free devices. New Zealand has banned hand-held cell phone use since 1 November 2009. Many states in the United States have banned texting on cell phones while driving. Illinois became the 17th American state to enforce this law.[63] As of July 2010, 30 states had banned texting while driving, with Kentucky becoming the most recent addition on 15 July.[64]

Public Health Law Research maintains a list of distracted driving laws in the United States. This database of laws provides a comprehensive view of the provisions of laws that restrict the use of mobile communication devices while driving for all 50 states and the District of Columbia between 1992 when first law was passed, through 1 December 2010. The dataset contains information on 22 dichotomous, continuous or categorical variables including, for example, activities regulated (e.g., texting versus talking, hands-free versus handheld), targeted populations, and exemptions.[65]

In 2010, an estimated 1500 pedestrians were injured in the US while using a cellphone and some jurisdictions have attempted to ban pedestrians from using their cellphones.[66][67]

Health effects

The effect of mobile phone radiation on human health is the subject of recent[when?] interest and study, as a result of the enormous increase in mobile phone usage throughout the world. Mobile phones use electromagnetic radiation in the microwave range, which some believe may be harmful to human health. A large body of research exists, both epidemiological and experimental, in non-human animals and in humans. The majority of this research shows no definite causative relationship between exposure to mobile phones and harmful biological effects in humans. This is often paraphrased simply as the balance of evidence showing no harm to humans from mobile phones, although a significant number of individual studies do suggest such a relationship, or are inconclusive. Other digital wireless systems, such as data communication networks, produce similar radiation.[citation needed]

On 31 May 2011, the World Health Organization stated that mobile phone use may possibly represent a long-term health risk,[68][69] classifying mobile phone radiation as "possibly carcinogenic to humans" after a team of scientists reviewed studies on mobile phone safety.[70] The mobile phone is in category 2B, which ranks it alongside coffee and other possibly carcinogenic substances.[71][72]

Some recent[when?] studies have found an association between mobile phone use and certain kinds of brain and salivary gland tumors. Lennart Hardell and other authors of a 2009 meta-analysis of 11 studies from peer-reviewed journals concluded that cell phone usage for at least ten years "approximately doubles the risk of being diagnosed with a brain tumor on the same ('ipsilateral') side of the head as that preferred for cell phone use".[73]

One study of past mobile phone use cited in the report showed a "40% increased risk for gliomas (brain cancer) in the highest category of heavy users (reported average: 30 minutes per day over a 10‐year period)".[74] This is a reversal of the study's prior position that cancer was unlikely to be caused by cellular phones or their base stations and that reviews had found no convincing evidence for other health effects.[69][75] However, a study published 24 March 2012, in the British Medical Journal questioned these estimates because the increase in brain cancers has not paralleled the increase in mobile phone use.[76] Certain countries, including France, have warned against the use of mobile phones by minors in particular, due to health risk uncertainties.[77] Mobile pollution by transmitting electromagnetic waves can be decreased up to 90% by adopting the circuit as designed in mobile phone and mobile exchange.[78]

In May 2016, preliminary findings of a long-term study by the U.S. government suggested that radio-frequency (RF) radiation, the type emitted by cell phones, can cause cancer.[79][80]

Educational impact

A study by the London School of Economics found that banning mobile phones in schools could increase pupils' academic performance, providing benefits equal to one extra week of schooling per year.[81]

Electronic waste regulation

Scrapped mobile phones.

Studies have shown that around 40–50% of the environmental impact of mobile phones occurs during the manufacture of their printed wiring boards and integrated circuits.[82]

The average user replaces their mobile phone every 11 to 18 months,[83] and the discarded phones then contribute to electronic waste. Mobile phone manufacturers within Europe are subject to the WEEE directive, and Australia has introduced a mobile phone recycling scheme.[84]

Apple Inc. had an advanced robotic disassembler and sorter called Liam specifically for recycling outdated or broken iPhones.[350]

Theft

According to the Federal Communications Commission, one out of three robberies involve the theft of a cellular phone.[citation needed] Police data in San Francisco show that half of all robberies in 2012 were thefts of cellular phones.[citation needed] An online petition on Change.org, called Secure our Smartphones, urged smartphone manufacturers to install kill switches in their devices to make them unusable if stolen. The petition is part of a joint effort by New York Attorney General Eric Schneiderman and San Francisco District Attorney George Gascón and was directed to the CEOs of the major smartphone manufacturers and telecommunication carriers.[85] On Monday, 10 June 2013, Apple announced that it would install a "kill switch" on its next iPhone operating system, due to debut in October 2013.[86]

All mobile phones have a unique identifier called IMEI. Anyone can report their phone as lost or stolen with their Telecom Carrier, and the IMEI would be blacklisted with a central registry.[87] Telecom carriers, depending upon local regulation can or must implement blocking of blacklisted phones in their network. There are, however, a number of ways to circumvent a blacklist. One method is to send the phone to a country where the telecom carriers are not required to implement the blacklisting and sell it there,[88] another involves altering the phone's IMEI number.[89] Even so, mobile phones typically have less value on the second-hand market if the phones original IMEI is blacklisted.

An unusual example of a phone bill caused by theft (reported on 28 June 2018) was when a biological group in Poland put a GPS tracker on a white stork and released it; during autumn migration over the Blue Nile valley in eastern Sudan someone got hold of the stork's GPS tracker, and found in it a mobile-phone-type sim card, which he put in his mobile phone, and made 20 hours of calls on it, running up a bill of over 10,000 Polish zlotys (= $2700) for the biological group.[90]

Conflict minerals

Demand for metals used in mobile phones and other electronics fuelled the Second Congo War, which claimed almost 5.5 million lives.[91] In a 2012 news story, The Guardian reported: "In unsafe mines deep underground in eastern Congo, children are working to extract minerals essential for the electronics industry. The profits from the minerals finance the bloodiest conflict since the second world war; the war has lasted nearly 20 years and has recently flared up again. ... For the last 15 years, the Democratic Republic of the Congo has been a major source of natural resources for the mobile phone industry."[92] The company Fairphone has worked to develop a mobile phone that does not contain conflict minerals.

See also

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Further reading

External links