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82-457: Near-field communication ( NFC ) is a set of communication protocols that enables communication between two electronic devices over a distance of 4 cm ( 1 + 1 ⁄ 2  in) or less. NFC offers a low-speed connection through a simple setup that can be used for the bootstrapping of capable wireless connections. Like other proximity card technologies, NFC is based on inductive coupling between two electromagnetic coils present on

164-478: A personal area network . GSMA defined a platform for the deployment of GSMA NFC Standards within mobile handsets. GSMA's efforts include, Single Wire Protocol , testing and certification and secure element. The GSMA standards surrounding the deployment of NFC protocols (governed by NFC Forum ) on mobile handsets are neither exclusive nor universally accepted. For example, Google's deployment of Host Card Emulation on Android KitKat provides for software control of

246-402: A tunneling arrangement to accommodate the connection of dissimilar networks. For example, IP may be tunneled across an Asynchronous Transfer Mode (ATM) network. Protocol layering forms the basis of protocol design. It allows the decomposition of single, complex protocols into simpler, cooperating protocols. The protocol layers each solve a distinct class of communication problems. Together,

328-539: A NFC-enabled device such as a smartphone . NFC communicating in one or both directions uses a frequency of 13.56 MHz in the globally available unlicensed radio frequency ISM band , compliant with the ISO/IEC 18000-3 air interface standard at data rates ranging from 106 to 848 kbit/s. The NFC Forum has helped define and promote the technology, setting standards for certifying device compliance. Secure communications are available by applying encryption algorithms as

410-403: A battery and can transmit up to 2000 meters (6,600 feet) in optimum conditions. RFID-based Asset Tracking requires an infrastructure to be put in place before the whereabouts of tags may be ascertained. An asset tracking system can record the location and usage of the assets and generate various reports. Unlike traditional barcode labels, RFID tags can be read faster and have higher durability. RFID

492-669: A coarse hierarchy of functional layers defined in the Internet Protocol Suite . The first two cooperating protocols, the Transmission Control Protocol (TCP) and the Internet Protocol (IP) resulted from the decomposition of the original Transmission Control Program, a monolithic communication protocol, into this layered communication suite. The OSI model was developed internationally based on experience with networks that predated

574-640: A company or manufacturer, but can be utilized immediately with an NFC-equipped smartphone and an NFC tag. The NFC Forum published the Signature Record Type Definition (RTD) 2.0 in 2015 to add integrity and authenticity for NFC Tags. This specification allows an NFC device to verify tag data and identify the tag author. NFC has been used in video games starting with Skylanders: Spyro's Adventure . These are customizable figurines which contain personal data with each figure, so no two figures are exactly alike. Nintendo's Wii U GamePad

656-599: A computer environment (such as ease of mechanical parsing and improved bandwidth utilization ). Network applications have various methods of encapsulating data. One method very common with Internet protocols is a text oriented representation that transmits requests and responses as lines of ASCII text, terminated by a newline character (and usually a carriage return character). Examples of protocols that use plain, human-readable text for its commands are FTP ( File Transfer Protocol ), SMTP ( Simple Mail Transfer Protocol ), early versions of HTTP ( Hypertext Transfer Protocol ), and

738-405: A de facto standard operating system like Linux does not have this negative grip on its market, because the sources are published and maintained in an open way, thus inviting competition. Asset tracking 'Passive' RFID tags broadcast their location but have limited transmission range (typically a few meters). Longer-range "smart tags" use 'active' RFID -where a radio transmitter is powered by

820-450: A future possible alternatives to NFC technology due to further distances of data transmission, as well as Bluetooth and wireless technology. NFC is a set of short-range wireless technologies, typically requiring a separation of 10 cm ( 3 + 7 ⁄ 8  in) or less. NFC operates at 13.56  MHz on ISO/IEC 18000-3 air interface and at rates ranging from 106 kbit/s to 424 kbit/s. NFC always involves an initiator and

902-428: A lower transfer rate than Bluetooth low energy . With NFC, instead of performing manual configurations to identify devices, the connection between two NFC devices is automatically established in less than .1 second. The maximum data transfer rate of NFC (424 kbit/s) is slower than that of Bluetooth V2.1 (2.1 Mbit/s). NFC's maximum working distance of less than 20 cm ( 7 + 7 ⁄ 8  in) reduces

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984-456: A machine rather than a human being. Binary protocols have the advantage of terseness, which translates into speed of transmission and interpretation. Binary have been used in the normative documents describing modern standards like EbXML , HTTP/2 , HTTP/3 and EDOC . An interface in UML may also be considered a binary protocol. Getting the data across a network is only part of the problem for

1066-686: A modified Miller coding with 100 percent modulation is used. In all other cases Manchester coding is used with a modulation ratio of 10 percent. Every active NFC device can work in one or more of three modes: NFC tags are passive data stores which can be read, and under some circumstances written to, by an NFC device. They typically contain data (as of 2015 between 96 and 8,192 bytes) and are read-only in normal use, but may be rewritable. Applications include secure personal data storage (e.g. debit or credit card information, loyalty program data, personal identification numbers (PINs), contacts). NFC tags can be custom-encoded by their manufacturers or use

1148-457: A networking protocol, the protocol software modules are interfaced with a framework implemented on the machine's operating system. This framework implements the networking functionality of the operating system. When protocol algorithms are expressed in a portable programming language the protocol software may be made operating system independent. The best-known frameworks are the TCP/IP model and

1230-675: A new Reader Mode to act as readers for HCE cards and other NFC-based transactions. On September 9, 2014, Apple announced support for NFC-powered transactions as part of Apple Pay . With the introduction of iOS 11, Apple devices allow third-party developers to read data from NFC tags. As of 2022, there are five major NFC apps available in the UK: Apple Pay, Google Pay, Samsung Pay, Barclays Contactless Mobile and Fitbit Pay. The UK Finance's UK Payment Markets Summary 2021 looked at Apple Pay, Google Pay and Samsung Pay and found 17.3 million UK adults had registered for mobile payment (up 75% from

1312-417: A packet-switched network, rather than this being a service of the network itself. His team was the first to tackle the highly complex problem of providing user applications with a reliable virtual circuit service while using a best-effort service , an early contribution to what will be the Transmission Control Protocol (TCP). Bob Metcalfe and others at Xerox PARC outlined the idea of Ethernet and

1394-498: A platform for the deployment of GSMA NFC Standards within mobile handsets. GSMA's efforts include Trusted Services Manager, Single Wire Protocol , testing/certification and secure element. NFC-enabled portable devices can be provided with application software , for example to read electronic tags or make payments when connected to an NFC-compliant system. These are standardized to NFC protocols, replacing proprietary technologies used by earlier systems. A patent licensing program for NFC

1476-554: A protocol. The data received has to be evaluated in the context of the progress of the conversation, so a protocol must include rules describing the context. These kinds of rules are said to express the syntax of the communication. Other rules determine whether the data is meaningful for the context in which the exchange takes place. These kinds of rules are said to express the semantics of the communication. Messages are sent and received on communicating systems to establish communication. Protocols should therefore specify rules governing

1558-565: A reference model for communication standards led to the OSI model , published in 1984. For a period in the late 1980s and early 1990s, engineers, organizations and nations became polarized over the issue of which standard , the OSI model or the Internet protocol suite, would result in the best and most robust computer networks. The information exchanged between devices through a network or other media

1640-478: A set of cooperating processes that manipulate shared data to communicate with each other. This communication is governed by well-understood protocols, which can be embedded in the process code itself. In contrast, because there is no shared memory , communicating systems have to communicate with each other using a shared transmission medium . Transmission is not necessarily reliable, and individual systems may use different hardware or operating systems. To implement

1722-673: A single communication. A group of protocols designed to work together is known as a protocol suite; when implemented in software they are a protocol stack . Internet communication protocols are published by the Internet Engineering Task Force (IETF). The IEEE (Institute of Electrical and Electronics Engineers) handles wired and wireless networking and the International Organization for Standardization (ISO) handles other types. The ITU-T handles telecommunications protocols and formats for

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1804-456: A standardization process. Such protocols are referred to as de facto standards . De facto standards are common in emerging markets, niche markets, or markets that are monopolized (or oligopolized ). They can hold a market in a very negative grip, especially when used to scare away competition. From a historical perspective, standardization should be seen as a measure to counteract the ill-effects of de facto standards. Positive exceptions exist;

1886-406: A surveillance similar to FAA's Automatic dependent surveillance – broadcast (ADS-B). For indoor asset tracking Wi-fi combined with another technology like IR has been used. Bluetooth and LoRa technology have also been used, and may provide more accuracy even if these radio technologies weren't primarily developed for location tracking. In order to position an asset via Bluetooth or LoRa, which

1968-945: A target; the initiator actively generates an RF field that can power a passive target. This enables NFC targets to take very simple form factors such as unpowered tags, stickers, key fobs, or cards. NFC peer-to-peer communication is possible, provided both devices are powered. NFC tags contain data and are typically read-only, but may be writable. They can be custom-encoded by their manufacturers or use NFC Forum specifications. The tags can securely store personal data such as debit and credit card information, loyalty program data, PINs and networking contacts, among other information. The NFC Forum defines five types of tags that provide different communication speeds and capabilities in terms of configurability, memory, security, data retention and write endurance. As with proximity card technology, NFC uses inductive coupling between two nearby loop antennas effectively forming an air-core transformer . Because

2050-430: A transfer mechanism of a protocol is comparable to a central processing unit (CPU). The framework introduces rules that allow the programmer to design cooperating protocols independently of one another. In modern protocol design, protocols are layered to form a protocol stack. Layering is a design principle that divides the protocol design task into smaller steps, each of which accomplishes a specific part, interacting with

2132-1379: A universal radio. In this HCE Deployment the NFC protocol is leveraged without the GSMA standards. Other standardization bodies involved in NFC include: NFC allows one- and two-way communication between endpoints, suitable for many applications. NFC devices can act as electronic identity documents and keycards . They are used in contactless payment systems and allow mobile payment replacing or supplementing systems such as credit cards and electronic ticket smart cards. These are sometimes called NFC/CTLS or CTLS NFC , with contactless abbreviated as CTLS . NFC can be used to share small files such as contacts and for bootstrapping fast connections to share larger media such as photos, videos, and other files. NFC devices can be used in contactless payment systems, similar to those used in credit cards and electronic ticket smart cards, and allow mobile payment to replace/supplement these systems. In Android 4.4, Google introduced platform support for secure NFC-based transactions through Host Card Emulation (HCE), for payments, loyalty programs, card access, transit passes and other custom services. HCE allows any Android 4.4 app to emulate an NFC smart card, letting users initiate transactions with their device. Apps can use

2214-454: A vehicle's battery. The frequency with which the position of the device must be known or available dictates the quality, size or type of GPS asset tracker required. It is common for asset tracking devices to fail due to Faraday cage effects as a huge proportion of the worlds assets are moved via intermodal containers . However modern tracking technology has now seen advances in signal transmission that allows enough signal strength reception from

2296-505: Is a pan-European consortium supported by the European Commission 's Information Society Technologies program. StoLPaN will examine the potential for NFC local wireless mobile communication. NFC Forum is a non-profit industry association formed on March 18, 2004, by NXP Semiconductors , Sony and Nokia to advance the use of NFC wireless interaction in consumer electronics, mobile devices and PCs. Its specifications include

2378-420: Is a soccer ball that contains an NFC chip within. The chip enables users to interact with the ball using a smartphone. NFC and Bluetooth are both relatively short-range communication technologies available on mobile phones . NFC operates at slower speeds than Bluetooth and has a much shorter range, but consumes far less power and doesn't require pairing. NFC sets up more quickly than standard Bluetooth, but has

2460-546: Is able to eavesdrop the RF signal depends on multiple parameters, but is typically less than 10 meters. Also, eavesdropping is highly affected by the communication mode. A passive device that doesn't generate its own RF field is much harder to eavesdrop on than an active device. An attacker can typically eavesdrop within 10 m of an active device and 1 m for passive devices. Because NFC devices usually include ISO/IEC 14443 protocols, relay attacks are feasible. For this attack

2542-516: Is at a premium and high power charging is less critical. The NFC Forum also facilitates a certification program, labeled as Test Release 13.1 (TR13.1), ensuring that products adhere to the WLC 2.0 specification. This certification aims to establish trust and consistency across NFC implementations, minimizing risks for manufacturers and providing assurance to consumers about the reliability and functionality of their NFC-enabled wireless charging devices. NFC

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2624-524: Is done for credit cards and if they fit the criteria for being considered a personal area network . NFC standards cover communications protocols and data exchange formats and are based on existing radio-frequency identification (RFID) standards including ISO/IEC 14443 and FeliCa . The standards include ISO/IEC 18092 and those defined by the NFC Forum. In addition to the NFC Forum, the GSMA group defined

2706-556: Is especially suitable for smaller devices like earbuds, wearables, and other compact Internet of Things (IoT) appliances. Compared to the more widely known Qi wireless charging standard by the Wireless Power Consortium , which offers up to 15W of power over distances up to 4 cm ( 1 + 5 ⁄ 8  in), NFC WLC provides a lower power output but benefits from a significantly smaller antenna size. This makes NFC WLC an ideal solution for devices where space

2788-453: Is governed by rules and conventions that can be set out in communication protocol specifications. The nature of communication, the actual data exchanged and any state -dependent behaviors, is defined by these specifications. In digital computing systems, the rules can be expressed by algorithms and data structures . Protocols are to communication what algorithms or programming languages are to computations. Operating systems usually contain

2870-410: Is integrated in smart warehousing to track inventory and other assets. Realtime information of the tagged objects are obtained including the location, activity and other characteristics. Assets can be tracked via manually scanning barcodes such as QR codes . QR codes can be scanned using smartphones with cameras and dedicated apps, as well as with barcode readers . Latest trend in asset tracking

2952-449: Is referred to as communicating sequential processes (CSP). Concurrency can also be modeled using finite state machines , such as Mealy and Moore machines . Mealy and Moore machines are in use as design tools in digital electronics systems encountered in the form of hardware used in telecommunication or electronic devices in general. The literature presents numerous analogies between computer communication and programming. In analogy,

3034-532: Is rooted in radio-frequency identification technology (known as RFID) which allows compatible hardware to both supply power to and communicate with an otherwise unpowered and passive electronic tag using radio waves. This is used for identification, authentication and tracking . Similar ideas in advertising and industrial applications were not generally successful commercially, outpaced by technologies such as QR codes , barcodes and UHF RFID tags. Ultra-wideband (UWB) another radio technology has been hailed as

3116-557: Is standardized in: NFC incorporates a variety of existing standards including ISO/IEC 14443 Type A and Type B, and FeliCa (also simply named F or NFC-F). NFC-enabled phones work at a basic level with existing readers. In "card emulation mode" an NFC device should transmit, at a minimum, a unique ID number to a reader. In addition, NFC Forum defined a common data format called NFC Data Exchange Format (NDEF) that can store and transport items ranging from any MIME -typed object to ultra-short RTD-documents, such as URLs . The NFC Forum added

3198-408: Is the synchronization of software for receiving and transmitting messages of communication in proper sequencing. Concurrent programming has traditionally been a topic in operating systems theory texts. Formal verification seems indispensable because concurrent programs are notorious for the hidden and sophisticated bugs they contain. A mathematical approach to the study of concurrency and communication

3280-594: Is typically independent of how it is to be implemented . Communication protocols have to be agreed upon by the parties involved. To reach an agreement, a protocol may be developed into a technical standard . A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: protocols are to communication what programming languages are to computations . An alternate formulation states that protocols are to communication what algorithms are to computation . Multiple protocols often describe different aspects of

3362-665: Is under deployment by France Brevets, a patent fund created in 2011. This program was under development by Via Licensing Corporation, an independent subsidiary of Dolby Laboratories , and was terminated in May 2012. A platform-independent free and open source NFC library, libnfc , is available under the GNU Lesser General Public License . Present and anticipated applications include contactless transactions, data exchange and simplified setup of more complex communications such as Wi-Fi . In addition, when one of

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3444-590: Is using NFC . NFC technology simplifies tracking of assets by tapping the assets and getting the details. This is an advantage for tracking critical assets where user needs to see the condition of the asset to be tracked. Assets may also be tracked globally using devices which combine the GPS system and mobile phone and/or satellite phone technology. Such devices are known as GPS asset trackers and are different from other GPS tracking units in that they rely on an internal battery for power rather than being hard-wired to

3526-776: The National Physical Laboratory in the United Kingdom, it was written by Roger Scantlebury and Keith Bartlett for the NPL network . On the ARPANET , the starting point for host-to-host communication in 1969 was the 1822 protocol , written by Bob Kahn , which defined the transmission of messages to an IMP. The Network Control Program (NCP) for the ARPANET, developed by Steve Crocker and other graduate students including Jon Postel and Vint Cerf ,

3608-423: The OSI model . At the time the Internet was developed, abstraction layering had proven to be a successful design approach for both compiler and operating system design and, given the similarities between programming languages and communication protocols, the originally monolithic networking programs were decomposed into cooperating protocols. This gave rise to the concept of layered protocols which nowadays forms

3690-638: The PARC Universal Packet (PUP) for internetworking. Research in the early 1970s by Bob Kahn and Vint Cerf led to the formulation of the Transmission Control Program (TCP). Its RFC   675 specification was written by Cerf with Yogen Dalal and Carl Sunshine in December 1974, still a monolithic design at this time. The International Network Working Group agreed on a connectionless datagram standard which

3772-563: The Simple NDEF Exchange Protocol (SNEP) to the spec that allows sending and receiving messages between two NFC devices. The GSM Association (GSMA) is a trade association representing nearly 800 mobile telephony operators and more than 200 product and service companies across 219 countries. Many of its members have led NFC trials and are preparing services for commercial launch. GSM is involved with several initiatives: StoLPaN (Store Logistics and Payment with NFC)

3854-547: The finger protocol . Text-based protocols are typically optimized for human parsing and interpretation and are therefore suitable whenever human inspection of protocol contents is required, such as during debugging and during early protocol development design phases. A binary protocol utilizes all values of a byte , as opposed to a text-based protocol which only uses values corresponding to human-readable characters in ASCII encoding. Binary protocols are intended to be read by

3936-590: The public switched telephone network (PSTN). As the PSTN and Internet converge , the standards are also being driven towards convergence. The first use of the term protocol in a modern data-commutation context occurs in April 1967 in a memorandum entitled A Protocol for Use in the NPL Data Communications Network. Under the direction of Donald Davies , who pioneered packet switching at

4018-468: The GPS satellite system which can then be reported via GPRS to terrestrial networks. Mobile phones are personal devices. Asset tracking apps for smart devices had been used as a means of personal tracking and rescues. For example, Find My iPhone is an app and service provided by Apple; it was used in rescuing a missing person in deep ravine from a car accident after other attempts failed. There are also tracking apps combined with viewing functions used as

4100-520: The NFC Forum. NFC is standardized in ECMA-340 and ISO/IEC 18092. These standards specify the modulation schemes, coding, transfer speeds and frame format of the RF interface of NFC devices, as well as initialization schemes and conditions required for data collision-control during initialization for both passive and active NFC modes. They also define the transport protocol , including protocol activation and data-exchange methods. The air interface for NFC

4182-597: The adversary forwards the request of the reader to the victim and relays its answer to the reader in real time, pretending to be the owner of the victim's smart card. This is similar to a man-in-the-middle attack . One libnfc code example demonstrates a relay attack using two stock commercial NFC devices. This attack can be implemented using only two NFC-enabled mobile phones. NFC standards cover communications protocols and data exchange formats, and are based on existing RFID standards including ISO/IEC 14443 and FeliCa . The standards include ISO/IEC 18092 and those defined by

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4264-456: The approval or support of a standards organization , which initiates the standardization process. The members of the standards organization agree to adhere to the work result on a voluntary basis. Often the members are in control of large market shares relevant to the protocol and in many cases, standards are enforced by law or the government because they are thought to serve an important public interest, so getting approval can be very important for

4346-448: The basis of protocol design. Systems typically do not use a single protocol to handle a transmission. Instead they use a set of cooperating protocols, sometimes called a protocol suite . Some of the best-known protocol suites are TCP/IP , IPX/SPX , X.25 , AX.25 and AppleTalk . The protocols can be arranged based on functionality in groups, for instance, there is a group of transport protocols . The functionalities are mapped onto

4428-648: The configuration of Wi-Fi networks. Samsung Galaxy devices have a feature named S-Beam —an extension of Android Beam that uses NFC (to share MAC address and IP addresses ) and then uses Wi-Fi Direct to share files and documents. The advantage of using Wi-Fi Direct over Bluetooth is that it permits much faster data transfers, running up to 300 Mbit/s. NFC can be used for social networking , for sharing contacts, text messages and forums, links to photos, videos or files and entering multiplayer mobile games . NFC-enabled devices can act as electronic identity documents found in passports and ID cards, and keycards for

4510-549: The connected devices has Internet connectivity, the other can exchange data with online services. Near-field communication (NFC) technology not only supports data transmission but also enables wireless charging, providing a dual-functionality that is particularly beneficial for small, portable devices. The NFC Forum has developed a specific wireless charging specification, known as NFC Wireless Charging (WLC), which allows devices to charge with up to 1W of power over distances of up to 2 cm ( 3 ⁄ 4  in). This capability

4592-442: The content being carried: text-based and binary. A text-based protocol or plain text protocol represents its content in human-readable format , often in plain text encoded in a machine-readable encoding such as ASCII or UTF-8 , or in structured text-based formats such as Intel hex format , XML or JSON . The immediate human readability stands in contrast to native binary protocols which have inherent benefits for use in

4674-473: The distances involved are tiny compared to the wavelength of electromagnetic radiation (radio waves) of that frequency (about 22 metres), the interaction is described as near field . An alternating magnetic field is the main coupling factor and almost no power is radiated in the form of radio waves (which are electromagnetic waves, also involving an oscillating electric field ); that minimises interference between such devices and any radio communications at

4756-673: The field of computer networking, it has been historically criticized by many researchers as abstracting the protocol stack in this way may cause a higher layer to duplicate the functionality of a lower layer, a prime example being error recovery on both a per-link basis and an end-to-end basis. Commonly recurring problems in the design and implementation of communication protocols can be addressed by software design patterns . Popular formal methods of describing communication syntax are Abstract Syntax Notation One (an ISO standard) and augmented Backus–Naur form (an IETF standard). Finite-state machine models are used to formally describe

4838-438: The five distinct tag types that provide different communication speeds and capabilities covering flexibility, memory, security, data retention and write endurance. NFC Forum promotes implementation and standardization of NFC technology to ensure interoperability between devices and services. As of January 2020, the NFC Forum had over 120 member companies. NFC Forum promotes NFC and certifies device compliance and whether it fits in

4920-426: The horizontal message flows (and protocols) are between systems. The message flows are governed by rules, and data formats specified by protocols. The blue lines mark the boundaries of the (horizontal) protocol layers. The software supporting protocols has a layered organization and its relationship with protocol layering is shown in figure 5. To send a message on system A, the top-layer software module interacts with

5002-400: The industry specifications. Although the range of NFC is limited to a few centimeters, standard plain NFC is not protected against eavesdropping and can be vulnerable to data modifications. Applications may use higher-layer cryptographic protocols to establish a secure channel. The RF signal for the wireless data transfer can be picked up with antennas. The distance from which an attacker

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5084-643: The internet as a reference model for general communication with much stricter rules of protocol interaction and rigorous layering. Typically, application software is built upon a robust data transport layer. Underlying this transport layer is a datagram delivery and routing mechanism that is typically connectionless in the Internet. Packet relaying across networks happens over another layer that involves only network link technologies, which are often specific to certain physical layer technologies, such as Ethernet . Layering provides opportunities to exchange technologies when needed, for example, protocols are often stacked in

5166-476: The layers make up a layering scheme or model. Computations deal with algorithms and data; Communication involves protocols and messages; So the analog of a data flow diagram is some kind of message flow diagram. To visualize protocol layering and protocol suites, a diagram of the message flows in and between two systems, A and B, is shown in figure 3. The systems, A and B, both make use of the same protocol suite. The vertical flows (and protocols) are in-system and

5248-427: The layers, each layer solving a distinct class of problems relating to, for instance: application-, transport-, internet- and network interface-functions. To transmit a message, a protocol has to be selected from each layer. The selection of the next protocol is accomplished by extending the message with a protocol selector for each layer. There are two types of communication protocols, based on their representation of

5330-432: The likelihood of unwanted interception, making it particularly suitable for crowded areas that complicate correlating a signal with its transmitting physical device (and by extension, its user). Communications protocol A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity . The protocol defines

5412-402: The module directly below it and hands over the message to be encapsulated. The lower module fills in the header data in accordance with the protocol it implements and interacts with the bottom module which sends the message over the communications channel to the bottom module of system B. On the receiving system B the reverse happens, so ultimately the message gets delivered in its original form to

5494-470: The other parts of the protocol only in a small number of well-defined ways. Layering allows the parts of a protocol to be designed and tested without a combinatorial explosion of cases, keeping each design relatively simple. The communication protocols in use on the Internet are designed to function in diverse and complex settings. Internet protocols are designed for simplicity and modularity and fit into

5576-445: The pickup antenna may be quenched in an eddy current by nearby metallic surfaces, the tags may require a minimum separation from such surfaces. The ISO/IEC 18092 standard supports data rates of 106, 212 or 424 kbit/s . The communication takes place between an active "initiator" device and a target device which may either be: NFC employs two different codings to transfer data. If an active device transfers data at 106 kbit/s,

5658-457: The possible interactions of the protocol. and communicating finite-state machines For communication to occur, protocols have to be selected. The rules can be expressed by algorithms and data structures. Hardware and operating system independence is enhanced by expressing the algorithms in a portable programming language. Source independence of the specification provides wider interoperability. Protocol standards are commonly created by obtaining

5740-401: The protocol, creating incompatible versions on their networks. In some cases, this was deliberately done to discourage users from using equipment from other manufacturers. There are more than 50 variants of the original bi-sync protocol. One can assume, that a standard would have prevented at least some of this from happening. In some cases, protocols gain market dominance without going through

5822-539: The protocol. The need for protocol standards can be shown by looking at what happened to the Binary Synchronous Communications (BSC) protocol invented by IBM . BSC is an early link-level protocol used to connect two separate nodes. It was originally not intended to be used in a multinode network, but doing so revealed several deficiencies of the protocol. In the absence of standardization, manufacturers and organizations felt free to enhance

5904-445: The rules, syntax , semantics , and synchronization of communication and possible error recovery methods . Protocols may be implemented by hardware , software , or a combination of both. Communicating systems use well-defined formats for exchanging various messages. Each message has an exact meaning intended to elicit a response from a range of possible responses predetermined for that particular situation. The specified behavior

5986-643: The same frequency or with other NFC devices much beyond its intended range. NFC operates within the globally available and unlicensed radio frequency ISM band of 13.56 MHz. Most of the RF energy is concentrated in the ±7 kHz bandwidth allocated for that band, but the emission's spectral width can be as wide as 1.8 MHz in order to support high data rates. Working distance with compact standard antennas and realistic power levels could be up to about 20 cm ( 7 + 7 ⁄ 8  in) (but practically speaking, working distances never exceed 10 cm or 3 + 7 ⁄ 8  in). Note that because

6068-514: The top module of system B. Program translation is divided into subproblems. As a result, the translation software is layered as well, allowing the software layers to be designed independently. The same approach can be seen in the TCP/IP layering. The modules below the application layer are generally considered part of the operating system. Passing data between these modules is much less expensive than passing data between an application program and

6150-506: The transmission. In general, much of the following should be addressed: Systems engineering principles have been applied to create a set of common network protocol design principles. The design of complex protocols often involves decomposition into simpler, cooperating protocols. Such a set of cooperating protocols is sometimes called a protocol family or a protocol suite, within a conceptual framework. Communicating systems operate concurrently. An important aspect of concurrent programming

6232-406: The transport layer. The boundary between the application layer and the transport layer is called the operating system boundary. Strictly adhering to a layered model, a practice known as strict layering, is not always the best approach to networking. Strict layering can have a negative impact on the performance of an implementation. Although the use of protocol layering is today ubiquitous across

6314-414: The use in fare cards , transit passes , login cards , car keys and access badges . NFC's short range and encryption support make it more suitable than less private RFID systems. NFC-equipped smartphones can be paired with NFC Tags or stickers that can be programmed by NFC apps. These programs can allow a change of phone settings, texting, app launching, or command execution. Such apps do not rely on

6396-541: The year before) and of those, 84% had made a mobile payment. NFC offers a low-speed connection with simple setup that can be used to bootstrap more capable wireless connections . For example, Android Beam software uses NFC to enable pairing and establish a Bluetooth connection when doing a file transfer and then disabling Bluetooth on both devices upon completion. Nokia, Samsung, BlackBerry and Sony have used NFC technology to pair Bluetooth headsets, media players and speakers with one tap. The same principle can be applied to

6478-415: Was first implemented in 1970. The NCP interface allowed application software to connect across the ARPANET by implementing higher-level communication protocols, an early example of the protocol layering concept. The CYCLADES network, designed by Louis Pouzin in the early 1970s was the first to implement the end-to-end principle , and make the hosts responsible for the reliable delivery of data on

6560-588: Was presented to the CCITT in 1975 but was not adopted by the CCITT nor by the ARPANET. Separate international research, particularly the work of Rémi Després , contributed to the development of the X.25 standard, based on virtual circuits , which was adopted by the CCITT in 1976. Computer manufacturers developed proprietary protocols such as IBM's Systems Network Architecture (SNA), Digital Equipment Corporation's DECnet and Xerox Network Systems . TCP software

6642-524: Was redesigned as a modular protocol stack, referred to as TCP/IP. This was installed on SATNET in 1982 and on the ARPANET in January 1983. The development of a complete Internet protocol suite by 1989, as outlined in RFC   1122 and RFC   1123 , laid the foundation for the growth of TCP/IP as a comprehensive protocol suite as the core component of the emerging Internet . International work on

6724-737: Was the first console system to include NFC technology out of the box. It was later included in the Nintendo 3DS range (being built into the New Nintendo 3DS/XL and in a separately sold reader which uses Infrared to communicate to older 3DS family consoles) and the Nintendo Switch range (being built within the right Joy-Con controller and directly in the Nintendo Switch Lite). The amiibo range of accessories utilize NFC technology to unlock features. Adidas Telstar 18

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