Wireless is a term used to define telecommunication and data transmission without wires. Show
In a broad sense, wireless refers to any telecommunications or data transfer in which electromagnetic waves -- rather than some form of wire or cable -- carry signals over all or part of the data communication path. The first wireless transmitters went on the air in the early 20th century using radiotelegraphy, which is radio communication using Morse Code or other coded signals. Later, as modulation made it possible to transmit voices and music via wireless, the medium came to be known as "radio." Modern wireless technology is largely concerned with data transmission. It enables all manner of data to be communicated over both short and long distances without the need for a physical wire. What is a wireless network?A wireless network is a grouping, or network, of multiple devices where data is sent and received over radio frequencies. Wireless networks are different than wired networks, where one end of the data connection is physically connected by a cable to enable communication with the other end. Wireless networks remove the need for fixed wired data cabling within an organization or network to connect different endpoint computing devices -- such as tablets, laptops and smartphones -- and embedded and peripheral devices. Wireless backhaul is often part of large service provider networks, enabling the connection of the wireless network to a fixed network for transmission. Wireless networks generally include some form of radio transmission for broadcasting and receiving wireless signals across a specified range of electromagnetic radiation spectrum, commonly referred to simply as "spectrum." Transmission of data across a wireless network is typically done via antennas, which are often small, embedded pieces of hardware within a given device. Different wireless networks will use various frequency ranges of spectrum. Within the spectrum, there are also different channels to help reduce the risk congestion within a given spectrum frequency. Types of wireless networksThere are multiple types of wireless networks that serve different needs, including:
Types of cellular networksThere are several types of cellular networks used to enable data and voice communications with smartphones. For much of the 1990s and 2000s, the following two primary types of cellular networks were used for mobile data and voice communications:
GSM and CDMA each had their own access methodologies that applied to 2G and 3G cellular specifications. With the advent of 4G/LTE and 5G in the 2000s, carriers are retiring their older CDMA and GSM networks. Modern cellular networks are typically defined in terms of which generation of wireless standards is supported.
What is the difference between Wi-Fi and wireless?Wireless communication is any transmission that occurs without the use of a cable or wire. In contrast, Wi-Fi is a specific subset of wireless that is defined by a set of technical specifications outlined by IEEE (Institute of Electrical and Electronics Engineers) under the designation 802.11. There are multiple Wi-Fi standards, including 802.11a/b/c/g/n/ac/ax, with each providing different performance characteristics. In recent years, at the behest of the Wi-Fi Alliance, rather than referring to Wi-Fi standards by their IEEE designations, the 802.11ac and 802.11ax specifications have been branded as Wi-Fi 5 and Wi-Fi 6 respectively. Wi-Fi is typically enabled on WLANs, with the use of a wireless access point or a wireless router, which broadcasts a service set identifier beacon. An endpoint device or user with a Wi-Fi-enabled network interface can then choose to connect to a given access point to enable the Wi-Fi connection. Examples of wireless equipmentAn ever-expanding array of wireless equipment enables users to stay connected without being tethered by wires. Common examples of wireless equipment include the following:
Wireless communication (or just wireless, when the context allows) is the transfer of information between two or more points that do not use an electrical conductor as a medium for the transfer. The most common wireless technologies use radio waves. With radio waves, intended distances can be short, such as a few meters for Bluetooth or as far as millions of kilometers for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mouse, keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Somewhat less common methods of achieving wireless communications include the use of other electromagnetic wireless technologies, such as light, magnetic, or electric fields or the use of sound.
The term wireless has been used twice in communications history, with slightly different meaning. It was initially used from about 1890 for the first radio transmitting and receiving technology, as in wireless telegraphy, until the new word radio replaced it around 1920. Radios in the UK that were not portable continued to be referred to as wireless sets into the 1960s.[dubious ] The term was revived in the 1980s and 1990s mainly to distinguish digital devices that communicate without wires, such as the examples listed in the previous paragraph, from those that require wires or cables. This became its primary usage in the 2000s, due to the advent of technologies such as mobile broadband, Wi-Fi and Bluetooth. Wireless operations permit services, such as mobile and interplanetary communications, that are impossible or impractical to implement with the use of wires. The term is commonly used in the telecommunications industry to refer to telecommunications systems (e.g. radio transmitters and receivers, remote controls, etc.) which use some form of energy (e.g. radio waves and acoustic energy) to transfer information without the use of wires.[1][2][3] Information is transferred in this manner over both short and long distances. Bell and Tainter's photophone, of 1880. The first wireless telephone conversation occurred in 1880, when Alexander Graham Bell and Charles Sumner Tainter invented the photophone, a telephone that sent audio over a beam of light. The photophone required sunlight to operate, and a clear line of sight between transmitter and receiver. These factors greatly decreased the viability of the photophone in any practical use.[4] It would be several decades before the photophone's principles found their first practical applications in military communications and later in fiber-optic communications. Electric wireless technologyEarly wirelessA number of wireless electrical signaling schemes including sending electric currents through water and the ground using electrostatic and electromagnetic induction were investigated for telegraphy in the late 19th century before practical radio systems became available. These included a patented induction system by Thomas Edison allowing a telegraph on a running train to connect with telegraph wires running parallel to the tracks, a William Preece induction telegraph system for sending messages across bodies of water, and several operational and proposed telegraphy and voice earth conduction systems. The Edison system was used by stranded trains during the Great Blizzard of 1888 and earth conductive systems found limited use between trenches during World War I but these systems were never successful economically. Radio wavesMarconi transmitting the first radio signal across the Atlantic. In 1894, Guglielmo Marconi began developing a wireless telegraph system using radio waves, which had been known about since proof of their existence in 1888 by Heinrich Hertz, but discounted as a communication format since they seemed, at the time, to be a short range phenomenon.[5] Marconi soon developed a system that was transmitting signals way beyond distances anyone could have predicted (due in part to the signals bouncing off the then unknown ionosphere). Marconi and Karl Ferdinand Braun were awarded the 1909 Nobel Prize for Physics for their contribution to this form of wireless telegraphy. Millimetre wave communication was first investigated by Jagadish Chandra Bose during 1894–1896, when he reached an extremely high frequency of up to 60 GHz in his experiments.[6] He also introduced the use of semiconductor junctions to detect radio waves,[7] when he patented the radio crystal detector in 1901.[8][9] Wireless revolutionPower MOSFETs, which are used in RF power amplifiers to boost radio frequency (RF) signals in long-distance wireless networks. The wireless revolution began in the 1990s,[10][11][12] with the advent of digital wireless networks leading to a social revolution, and a paradigm shift from wired to wireless technology,[13] including the proliferation of commercial wireless technologies such as cell phones, mobile telephony, pagers, wireless computer networks,[10] cellular networks, the wireless Internet, and laptop and handheld computers with wireless connections.[14] The wireless revolution has been driven by advances in radio frequency (RF) and microwave engineering,[10] and the transition from analog to digital RF technology,[13][14] which enabled a substantial increase in voice traffic along with the delivery of digital data such as text messaging, images and streaming media.[13] Wireless communications can be via: RadioRadio and microwave communication carry information by modulating properties of electromagnetic waves transmitted through space. Specifically, the transmitter generates artificial electromagnetic waves by applying time-varying electric currents to its antenna. The waves travel away from the antenna until they eventually reach the antenna of a receiver, which induces an electrical current in the receiving antenna. This current can be detected and demodulated to recreate the information sent by the transmitter. Free-space opticalAn 8-beam free space optics laser link, rated for 1 Gbit/s at a distance of approximately 2 km. The receptor is the large disc in the middle, the transmitters the smaller ones. To the top and right corner a monocular for assisting the alignment of the two heads. Free-space optical communication (FSO) is an optical communication technology that uses light propagating in free space to transmit wirelessly data for telecommunications or computer networking. "Free space" means the light beams travel through the open air or outer space. This contrasts with other communication technologies that use light beams traveling through transmission lines such as optical fiber or dielectric "light pipes". The technology is useful where physical connections are impractical due to high costs or other considerations. For example, free space optical links are used in cities between office buildings which are not wired for networking, where the cost of running cable through the building and under the street would be prohibitive. Another widely used example is consumer IR devices such as remote controls and IrDA (Infrared Data Association) networking, which is used as an alternative to WiFi networking to allow laptops, PDAs, printers, and digital cameras to exchange data. SonicSonic, especially ultrasonic short range communication involves the transmission and reception of sound. Electromagnetic inductionElectromagnetic induction only allows short-range communication and power transmission. It has been used in biomedical situations such as pacemakers, as well as for short-range RFID tags. Common examples of wireless equipment include:[15]
AM and FM radios and other electronic devices make use of the electromagnetic spectrum. The frequencies of the radio spectrum that are available for use for communication are treated as a public resource and are regulated by organizations such as the American Federal Communications Commission, Ofcom in the United Kingdom, the international ITU-R or the European ETSI. Their regulations determine which frequency ranges can be used for what purpose and by whom. In the absence of such control or alternative arrangements such as a privatized electromagnetic spectrum, chaos might result if, for example, airlines did not have specific frequencies to work under and an amateur radio operator was interfering with a pilot's ability to land an aircraft. Wireless communication spans the spectrum from 9 kHz to 300 GHz.[citation needed] One of the best-known examples of wireless technology is the mobile phone, also known as a cellular phone, with more than 6.6 billion mobile cellular subscriptions worldwide as of the end of 2010.[17] These wireless phones use radio waves from signal-transmission towers to enable their users to make phone calls from many locations worldwide. They can be used within range of the mobile telephone site used to house the equipment required to transmit and receive the radio signals from these instruments.[18] Data communicationsWireless data communications allows wireless networking between desktop computers, laptops, tablet computers, cell phones and other related devices. The various available technologies differ in local availability, coverage range and performance,[19] and in some circumstances users employ multiple connection types and switch between them using connection manager software[20][21] or a mobile VPN to handle the multiple connections as a secure, single virtual network.[22] Supporting technologies include: Wi-Fi is a wireless local area network that enables portable computing devices to connect easily with other devices, peripherals, and the Internet.[citation needed] Standardized as IEEE 802.11 a, b, g, n, ac, ax, Wi-Fi has link speeds similar to older standards of wired Ethernet. Wi-Fi has become the de facto standard for access in private homes, within offices, and at public hotspots.[23] Some businesses charge customers a monthly fee for service, while others have begun offering it free in an effort to increase the sales of their goods.[24]Cellular data service offers coverage within a range of 10-15 miles from the nearest cell site.[19] Speeds have increased as technologies have evolved, from earlier technologies such as GSM, CDMA and GPRS, through 3G, to 4G networks such as W-CDMA, EDGE or CDMA2000.[25][26] As of 2018, the proposed next generation is 5G.Low-power wide-area networks (LPWAN) bridge the gap between Wi-Fi and Cellular for low bitrate Internet of things (IoT) applications. Mobile-satellite communications may be used where other wireless connections are unavailable, such as in largely rural areas[27] or remote locations.[19] Satellite communications are especially important for transportation, aviation, maritime and military use.[28]Wireless sensor networks are responsible for sensing noise, interference, and activity in data collection networks. This allows us to detect relevant quantities, monitor and collect data, formulate clear user displays, and to perform decision-making functions[29]Wireless data communications are used to span a distance beyond the capabilities of typical cabling in point-to-point communication and point-to-multipoint communication, to provide a backup communications link in case of normal network failure, to link portable or temporary workstations, to overcome situations where normal cabling is difficult or financially impractical, or to remotely connect mobile users or networks. PeripheralsPeripheral devices in computing can also be connected wirelessly, as part of a Wi-Fi network or directly via an optical or radio-frequency (RF) peripheral interface. Originally these units used bulky, highly local transceivers to mediate between a computer and a keyboard and mouse; however, more recent generations have used smaller, higher-performance devices. Radio-frequency interfaces, such as Bluetooth or Wireless USB, provide greater ranges of efficient use, usually up to 10 feet, but distance, physical obstacles, competing signals, and even human bodies can all degrade the signal quality.[30] Concerns about the security of wireless keyboards arose at the end of 2007, when it was revealed that Microsoft's implementation of encryption in some of its 27 MHz models was highly insecure.[31] Energy transferWireless energy transfer is a process whereby electrical energy is transmitted from a power source to an electrical load that does not have a built-in power source, without the use of interconnecting wires. There are two different fundamental methods for wireless energy transfer. Energy can be transferred using either far-field methods that involve beaming power/lasers, radio or microwave transmissions or near-field using electromagnetic induction.[32] Wireless energy transfer may be combined with wireless information transmission in what is known as Wireless Powered Communication.[33] In 2015, researchers at the University of Washington demonstrated far-field energy transfer using Wi-Fi signals to power cameras.[34] Medical technologiesNew wireless technologies, such as mobile body area networks (MBAN), have the capability to monitor blood pressure, heart rate, oxygen level and body temperature. The MBAN works by sending low powered wireless signals to receivers that feed into nursing stations or monitoring sites. This technology helps with the intentional and unintentional risk of infection or disconnection that arise from wired connections.[35]
Page 23G is the third generation of wireless mobile telecommunications technology. It was the upgrade over 2G, 2.5G, GPRS and 2.75G EDGE networks, offering faster data transfer, and better voice quality.[1] This network was superseded by 4G, and later on 5G. This network is based on a set of standards used for mobile devices and mobile telecommunications use services and networks that comply with the International Mobile Telecommunications-2000 (IMT-2000) specifications by the International Telecommunication Union. 3G finds application in wireless voice telephony, mobile Internet access, fixed wireless Internet access, video calls and mobile TV.[1]
3G telecommunication networks support services that provide an information transfer rate of at least 144 kbit/s.[2][3][4] Later 3G releases, often denoted 3.5G and 3.75G, also provide mobile broadband access of several Mbit/s to smartphones and mobile modems in laptop computers. This ensures it can be applied to wireless voice calls, mobile Internet access, fixed wireless Internet access, video calls and mobile TV technologies. A new generation of cellular standards has appeared approximately every tenth year since 1G systems were introduced in 1979 and the early to mid-1980s. Each generation is characterized by new frequency bands, higher data rates and non–backward-compatible transmission technology. The first commercial 3G networks were introduced in mid-2001.[5][6][7][8] Since the adoption of 4G and 5G networks, various countries have shut down their 3G networks or are in the process of doing so. Several telecommunications companies market wireless mobile Internet services as 3G, indicating that the advertised service is provided over a 3G wireless network. Services advertised as 3G are required to meet IMT-2000 technical standards, including standards for reliability and speed (data transfer rates). To meet the IMT-2000 standards, a system must provide peak data rates of at least 144 kbit/s.[4] However, many services advertised as 3G provide higher speed than the minimum technical requirements for a 3G service.[9] Subsequent 3G releases, denoted 3.5G and 3.75G, provided mobile broadband access of several Mbit/s for smartphones and mobile modems in laptop computers.[10] 3G branded standards:
The 3G systems and radio interfaces are based on spread spectrum radio transmission technology. While the GSM EDGE standard ("2.9G"), DECT cordless phones and Mobile WiMAX standards formally also fulfill the IMT-2000 requirements and are approved as 3G standards by ITU, these are typically not branded as 3G and are based on completely different technologies. The common standards complying with the IMT2000/3G standard are:
While DECT cordless phones and Mobile WiMAX standards formally also fulfill the IMT-2000 requirements, they are not usually considered due to their rarity and unsuitability for usage with mobile phones.[11] Break-up of 3G systemsThe 3G (UMTS and CDMA2000) research and development projects started in 1992. In 1999, ITU approved five radio interfaces for IMT-2000 as a part of the ITU-R M.1457 Recommendation; WiMAX was added in 2007.[12] There are evolutionary standards (EDGE and CDMA) that are backward-compatible extensions to pre-existing 2G networks as well as revolutionary standards that require all-new network hardware and frequency allocations. The cell phones use UMTS in combination with 2G GSM standards and bandwidths, but do not support EDGE. The latter group is the UMTS family, which consists of standards developed for IMT-2000, as well as the independently developed standards DECT and WiMAX, which were included because they fit the IMT-2000 definition. While EDGE fulfills the 3G specifications, most GSM/UMTS phones report EDGE ("2.75G") and UMTS ("3G") functionality.[13] 3G technology was the result of research and development work carried out by the International Telecommunication Union (ITU) in the early 1980s. 3G specifications and standards were developed in fifteen years. The technical specifications were made available to the public under the name IMT-2000. The communication spectrum between 400 MHz to 3 GHz was allocated for 3G. Both the government and communication companies approved the 3G standard. The first pre-commercial 3G network was launched by NTT DoCoMo in Japan in 1998,[14] branded as FOMA. It was first available in May 2001 as a pre-release (test) of W-CDMA technology. The first commercial launch of 3G was also by NTT DoCoMo in Japan on 1 October 2001, although it was initially somewhat limited in scope;[15][16] broader availability of the system was delayed by apparent concerns over its reliability.[17] The first European pre-commercial network was an UMTS network on the Isle of Man by Manx Telecom, the operator then-owned by British Telecom, and the first commercial network (also UMTS based W-CDMA) in Europe was opened for business by Telenor in December 2001 with no commercial handsets and thus no paying customers. The first network to go commercially live was by SK Telecom in South Korea on the CDMA-based 1xEV-DO technology in January 2002. By May 2002, the second South Korean 3G network was by KT on EV-DO and thus the South Koreans were the first to see competition among 3G operators. The first commercial United States 3G network was by Monet Mobile Networks, on CDMA2000 1x EV-DO technology, but the network provider later shut down operations. The second 3G network operator in the USA was Verizon Wireless in July 2002, also on CDMA2000 1x EV-DO. AT&T Mobility was also a true 3G UMTS network, having completed its upgrade of the 3G network to HSUPA. The first commercial United Kingdom 3G network was started by Hutchison Telecom which was originally behind Orange S.A.[18] In 2003, it announced first commercial third generation or 3G mobile phone network in the UK. The first pre-commercial demonstration network in the southern hemisphere was built in Adelaide, South Australia, by m.Net Corporation in February 2002 using UMTS on 2100 MHz. This was a demonstration network for the 2002 IT World Congress. The first commercial 3G network was launched by Hutchison Telecommunications branded as Three or "3" in June 2003.[19] In India, on 11 December 2008, the first 3G mobile and internet services were launched by a state-owned company, Mahanagar Telecom Nigam Limited (MTNL), within the metropolitan cities of Delhi and Mumbai. After MTNL, another state-owned company, Bharat Sanchar Nigam Limited (BSNL), began deploying the 3G networks country-wide. Emtel launched the first 3G network in Africa.[20] AdoptionJapan was one of the first countries to adopt 3G, the reason being the process of 3G spectrum allocation, which in Japan was awarded without much upfront cost. Frequency spectrum was allocated in the US and Europe based on auctioning, thereby requiring a huge initial investment for any company wishing to provide 3G services. European companies collectively paid over 100 billion dollars in their spectrum auctions.[21] Nepal Telecom adopted 3G Service for the first time in southern Asia. However, its 3G was relatively slow to be adopted in Nepal. In some instances, 3G networks do not use the same radio frequencies as 2G, so mobile operators must build entirely new networks and license entirely new frequencies, especially to achieve high data transmission rates. Other countries' delays were due to the expenses of upgrading transmission hardware, especially for UMTS, whose deployment required the replacement of most broadcast towers. Due to these issues and difficulties with deployment, many carriers could not or delayed the acquisition of these updated capabilities. In December 2007, 190 3G networks were operating in 40 countries and 154 HSDPA networks were operating in 71 countries, according to the Global Mobile Suppliers Association (GSA). In Asia, Europe, Canada, and the US, telecommunication companies use W-CDMA technology with the support of around 100 terminal designs to operate 3G mobile networks. The roll-out of 3G networks was delayed by the enormous costs of additional spectrum licensing fees in some countries. The license fees in some European countries were particularly high, bolstered by government auctions of a limited number of licenses and sealed bid auctions, and initial excitement over 3G's potential. This led to a telecoms crash that ran concurrently with similar crashes in the fibre-optic and dot.com fields. The 3G standard is perhaps well known because of a massive expansion of the mobile communications market post-2G and advances of the consumer mobile phone. An especially notable development during this time is the smartphone (for example, the iPhone, and the Android family), combining the abilities of a PDA with a mobile phone, leading to widespread demand for mobile internet connectivity. 3G has also introduced the term "mobile broadband" because its speed and capability made it a viable alternative for internet browsing, and USB Modems connecting to 3G networks, and now 4G became increasingly common. Market penetrationBy June 2007, the 200 millionth 3G subscriber had been connected of which 10 million were in Nepal and 8.2 million in India. This 200 millionth is only 6.7% of the 3 billion mobile phone subscriptions worldwide. (When counting CDMA2000 1x RTT customers—max bitrate 72% of the 200kbit/s which defines 3G—the total size of the nearly-3G subscriber base was 475 million as of June 2007, which was 15.8% of all subscribers worldwide.) In the countries where 3G was launched first – Japan and South Korea – 3G penetration is over 70%.[22] In Europe the leading country[when?] for 3G penetration is Italy with a third of its subscribers migrated to 3G. Other leading countries[when?] for 3G use include Nepal, UK, Austria, Australia and Singapore at the 32% migration level. According to ITU estimates,[23] as of Q4 2012 there were 2096 million active mobile-broadband[vague] subscribers worldwide out of a total of 6835 million subscribers—this is just over 30%. About half the mobile-broadband subscriptions are for subscribers in developed nations, 934 million out of 1600 million total, well over 50%. Note however that there is a distinction between a phone with mobile-broadband connectivity and a smart phone with a large display and so on—although according[24] to the ITU and informatandm.com the USA has 321 million mobile subscriptions, including 256 million that are 3G or 4G, which is both 80% of the subscriber base and 80% of the USA population, according[23] to ComScore just a year earlier in Q4 2011 only about 42% of people surveyed in the USA reported they owned a smart phone. In Japan, 3G penetration was similar at about 81%, but smart phone ownership was lower at about 17%.[23] In China, there were 486.5 million 3G subscribers in June 2014,[25] in a population of 1,385,566,537 (2013 UN estimate). Decline and decommissionsSince the increasing adoption of 4G networks across the globe, 3G use has been in decline. Several operators around the world have already or are in the process of shutting down their 3G networks. In several places, 3G is being shut down while its older predecessor 2G is being kept in operation – Vodafone Europe is doing this, citing that 2G is a useful low-power fall-back.[26] EE have also another that 3G will be phased out in 2023 with the spectrum being used to enhance 5G capacity.[27] In the United States, Verizon was planning to shut down its 3G services at the end of 2020 (later delayed to the end of 2022[28]), while T-Mobile is planning to do so on 1 July 2022, with the networks formerly a part of Sprint shutting down on 31 March 2022. AT&T shut down its 3G networks on 22 February 2022.[29][30] According to Consumer Reports, this shutdown will affect safety features from working on many older cars. Some of these cars can be upgraded, but other vehicles will lose the features permanently.[31] Other older technology, such as alarm systems and some IoT gadgets will be affected as well.[32] Any technology that depends on 3G for usage also become inoperable with the shutdown of 3G networks. The European Union plans to keep its member countries with 2G operating as a fallback, so 3G devices that are backwards compatible with 2G frequencies can continue to be used. But in countries like the United States that aren't aiming to keep 2G around for much longer, devices supporting only 3G and backwards compatible with 2G will soon be out of service.[33] It has been estimated that there are almost 8,000 patents declared essential (FRAND) related to the 483 technical specifications which form the 3GPP and 3GPP2 standards.[34][35] Twelve companies accounted in 2004 for 90% of the patents (Qualcomm, Ericsson, Nokia, Motorola, Philips, NTT DoCoMo, Siemens, Mitsubishi, Fujitsu, Hitachi, InterDigital, and Matsushita). Even then, some patents essential to 3G might not have been declared by their patent holders. It is believed that Nortel and Lucent have undisclosed patents essential to these standards.[35] Furthermore, the existing 3G Patent Platform Partnership Patent pool has little impact on FRAND protection because it excludes the four largest patent owners for 3G.[36][37] ITU has not provided a clear[38][vague] definition of the data rate that users can expect from 3G equipment or providers. Thus users sold 3G service may not be able to point to a standard and say that the rates it specifies are not being met. While stating in commentary that "it is expected that IMT-2000 will provide higher transmission rates: a minimum data rate of 2 Mbit/s for stationary or walking users, and 348 kbit/s in a moving vehicle,"[39] the ITU does not actually clearly specify minimum required rates, nor required average rates, nor what modes[clarification needed] of the interfaces qualify as 3G, so various[vague] data rates are sold as '3G' in the market. In a market implementation, 3G downlink data speeds defined by telecom service providers vary depending on the underlying technology deployed; up to 384kbit/s for UMTS (WCDMA), up to 7.2Mbit/sec for HSPA, and a theoretical maximum of 21.1 Mbit/s for HSPA+ and 42.2 Mbit/s for DC-HSPA+ (technically 3.5G, but usually clubbed under the tradename of 3G).[citation needed] Compare data speeds with 3.5G and 4G. Security3G networks offer greater security than their 2G predecessors. By allowing the UE (User Equipment) to authenticate the network it is attaching to, the user can be sure the network is the intended one and not an impersonator. 3G networks use the KASUMI block cipher instead of the older A5/1 stream cipher. However, a number of serious weaknesses in the KASUMI cipher have been identified.[40] In addition to the 3G network infrastructure security, end-to-end security is offered when application frameworks such as IMS are accessed, although this is not strictly a 3G property. Applications of 3GThe bandwidth and location information available to 3G devices gives rise to applications not previously available to mobile phone users. It became possible to conveniently surf the internet on a 3G network on the go with minimum hassle, and do many other tasks previously a slow and difficult hassle on 2G. Medical devices, fire alarms, ankle monitors use this network for accomplishing their designated tasks alongside mobile phone users.[41] This network marked a first for a cellular communications network to be used in such a wide variety of tasks, kick starting the beginning of widespread usage of cellular networks. Both 3GPP and 3GPP2 are working on the extensions to 3G standards that are based on an all-IP network infrastructure and using advanced wireless technologies such as MIMO. These specifications already display features characteristic for IMT-Advanced (4G), the successor of 3G. However, falling short of the bandwidth requirements for 4G (which is 1 Gbit/s for stationary and 100 Mbit/s for mobile operation), these standards are classified as 3.9G or Pre-4G. 3GPP plans to meet the 4G goals with LTE Advanced, whereas Qualcomm has halted UMB development in favour of the LTE family.[42] On 14 December 2009, Telia Sonera announced in an official press release that "We are very proud to be the first operator in the world to offer our customers 4G services."[43] With the launch of their LTE network, initially they are offering pre-4G (or beyond 3G) services in Stockholm, Sweden and Oslo, Norway.
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What short distance wireless standard is used to link cell phones computers and peripherals?
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