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63-468: In communications, Circuit Switched Data ( CSD ) (also named GSM data ) 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 After 2010 many telecommunication carriers dropped support for CSD, and CSD has been superseded by GPRS and EDGE (E-GPRS). CSD uses a single radio time slot to deliver 9.6 kbit/s data transmission to

126-488: A mass noun in singular form. This usage is common in everyday language and in technical and scientific fields such as software development and computer science . One example of this usage is the term " big data ". When used more specifically to refer to the processing and analysis of sets of data, the term retains its plural form. This usage is common in the natural sciences, life sciences, social sciences, software development and computer science, and grew in popularity in

189-618: A terminal -like interface over USB with V.42bis , and RFC   1144 data formats. Some models include an external antenna connector. Modem cards for laptop PCs, or external USB modems are available, similar in shape and size to a computer mouse , or a pendrive . A GPRS connection is established by reference to its access point name (APN). The APN defines the services such as wireless application protocol (WAP) access, short message service (SMS), multimedia messaging service (MMS), and for Internet communication services such as email and World Wide Web access. In order to set up

252-515: A Class A device must service GPRS and GSM networks together, it effectively needs two radios. To avoid this hardware requirement, a GPRS mobile device may implement the dual transfer mode (DTM) feature. A DTM-capable mobile can handle both GSM packets and GPRS packets with network coordination to ensure both types are not transmitted at the same time. Such devices are considered pseudo-Class A, sometimes referred to as "simple class A". Some networks have supported DTM since 2007 . USB 3G/GPRS modems have

315-452: A GPRS connection for a wireless modem , a user must specify an APN, optionally a user name and password, and very rarely an IP address , provided by the network operator. GSM module or GPRS modules are similar to modems, but there's one difference: the modem is an external piece of equipment, whereas the GSM module or GPRS module can be integrated within an electrical or electronic equipment. It

378-478: A bandwidth of 5*59.2 kbit/s = 296 kbit/s. In uplink direction, 3 timeslots can carry a bandwidth of 3*59.2 kbit/s = 177.6 kbit/s. Each multislot class identifies the following: The different multislot class specification is detailed in the Annex B of the 3GPP Technical Specification 45.002 (Multiplexing and multiple access on the radio path) The maximum speed of a GPRS connection offered in 2003

441-436: A basis for calculation, reasoning, or discussion. Data can range from abstract ideas to concrete measurements, including, but not limited to, statistics . Thematically connected data presented in some relevant context can be viewed as information . Contextually connected pieces of information can then be described as data insights or intelligence . The stock of insights and intelligence that accumulate over time resulting from

504-584: A climber's guidebook containing practical information on the best way to reach Mount Everest's peak may be considered "knowledge". "Information" bears a diversity of meanings that range from everyday usage to technical use. This view, however, has also been argued to reverse how data emerges from information, and information from knowledge. Generally speaking, the concept of information is closely related to notions of constraint, communication, control, data, form, instruction, knowledge, meaning, mental stimulus, pattern , perception, and representation. Beynon-Davies uses

567-404: A common view, data is collected and analyzed; data only becomes information suitable for making decisions once it has been analyzed in some fashion. One can say that the extent to which a set of data is informative to someone depends on the extent to which it is unexpected by that person. The amount of information contained in a data stream may be characterized by its Shannon entropy . Knowledge

630-668: A description of other data. A similar yet earlier term for metadata is "ancillary data." The prototypical example of metadata is the library catalog, which is a description of the contents of books. Whenever data needs to be registered, data exists in the form of a data document . Kinds of data documents include: Some of these data documents (data repositories, data studies, data sets, and software) are indexed in Data Citation Indexes , while data papers are indexed in traditional bibliographic databases, e.g., Science Citation Index . Gathering data can be accomplished through

693-553: A few decades. Scientific publishers and libraries have been struggling with this problem for a few decades, and there is still no satisfactory solution for the long-term storage of data over centuries or even for eternity. Data accessibility . Another problem is that much scientific data is never published or deposited in data repositories such as databases . In a recent survey, data was requested from 516 studies that were published between 2 and 22 years earlier, but less than one out of five of these studies were able or willing to provide

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756-406: A maximum number of 6 simultaneously used timeslots. If data traffic is concentrated in downlink direction the network will configure the connection for 5+1 operation. When more data is transferred in the uplink the network can at any time change the constellation to 4+2 or 3+3. Under the best reception conditions, i.e. when the best EDGE modulation and coding scheme can be used, 5 timeslots can carry

819-592: 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 CSD designed to provide higher data rates by means of more efficient channel coding and/or multiple (up to 4) time slots. It requires

882-442: 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

945-470: A primary source (the researcher is the first person to obtain the data) or a secondary source (the researcher obtains the data that has already been collected by other sources, such as data disseminated in a scientific journal). Data analysis methodologies vary and include data triangulation and data percolation. The latter offers an articulate method of collecting, classifying, and analyzing data using five possible angles of analysis (at least three) to maximize

1008-481: A session, a user is assigned to one pair of up-link and down-link frequency channels. This is combined with time domain statistical multiplexing which makes it possible for several users to share the same frequency channel. The packets have constant length, corresponding to a GSM time slot. The down-link uses first-come first-served packet scheduling, while the up-link uses a scheme very similar to reservation ALOHA (R-ALOHA). This means that slotted ALOHA (S-ALOHA)

1071-484: 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

1134-401: Is 25% of normal. CS-1 can achieve a user speed of only 8.0 kbit/s per time slot, but has 98% of normal coverage. Newer network equipment can adapt the transfer speed automatically depending on the mobile location. In addition to GPRS, there are two other GSM technologies which deliver data services: circuit-switched data (CSD) and high-speed circuit-switched data (HSCSD). In contrast to

1197-577: Is a 2G digital mobile phone technology for data transmission. It is a subset of General Packet Radio Service (GPRS) on the GSM network and improves upon it offering speeds close to 3G technology, hence the name 2.75G. It is also recognized as part of the International Mobile Telecommunications - 2000 (IMT-2000) standard. EDGE was deployed on GSM networks beginning in 2003 – initially by Cingular (now AT&T ) in

1260-580: Is a mobile data standard on the 2G cellular communication network's global system for mobile communications (GSM). Networks and mobile devices with GPRS started to roll out around the year 2001. At the time of introduction it offered for the first time seamless mobile data transmission using packet data for an "always-on" connection (eliminating the need to "dial-up"), providing improved Internet access for web , email , WAP services, and Multimedia Messaging Service (MMS). GPRS provides theoretical data rates of 56–114  kbit /s - faster than

1323-485: Is a more comprehensive record of international cellular service frequency assignments GPRS supports the following protocols: When TCP/IP is used, each phone can have one or more IP addresses allocated. GPRS will store and forward the IP packets to the phone even during handover . The TCP restores any packets lost (e.g. due to a radio noise induced pause). Devices supporting GPRS are grouped into three classes: Because

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1386-496: Is an embedded piece of hardware. A GSM mobile, on the other hand, is a complete embedded system in itself. It comes with embedded processors dedicated to provide a functional interface between the user and the mobile network. The upload and download speeds that can be achieved in GPRS depend on a number of factors such as: The multiple access methods used in GSM with GPRS are based on frequency-division duplex (FDD) and TDMA. During

1449-459: Is applied. The following table summarises the options. The least robust, but fastest, coding scheme (CS-4) is available near a base transceiver station (BTS), while the most robust coding scheme (CS-1) is used when the mobile station (MS) is further away from a BTS. Using the CS-4 it is possible to achieve a user speed of 20.0 kbit/s per time slot. However, using this scheme the cell coverage

1512-539: Is now maintained by the 3rd Generation Partnership Project (3GPP). The GPRS core network allows 2G , 3G and WCDMA mobile networks to transmit IP packets to external networks such as the Internet . The GPRS system is an integrated part of the GSM network switching subsystem . GPRS extends the GSM Packet circuit switched data capabilities and makes the following services possible: If SMS over GPRS

1575-459: 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

1638-408: 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

1701-405: Is the awareness of its environment that some entity possesses, whereas data merely communicates that knowledge. For example, the entry in a database specifying the height of Mount Everest is a datum that communicates a precisely-measured value. This measurement may be included in a book along with other data on Mount Everest to describe the mountain in a manner useful for those who wish to decide on

1764-443: Is the longevity of data. Scientific research generates huge amounts of data, especially in genomics and astronomy , but also in the medical sciences , e.g. in medical imaging . In the past, scientific data has been published in papers and books, stored in libraries, but more recently practically all data is stored on hard drives or optical discs . However, in contrast to paper, these storage devices may become unreadable after

1827-404: Is the plural of datum , "(thing) given," and the neuter past participle of dare , "to give". The first English use of the word "data" is from the 1640s. The word "data" was first used to mean "transmissible and storable computer information" in 1946. The expression "data processing" was first used in 1954. When "data" is used more generally as a synonym for "information", it is treated as

1890-498: Is used for reservation inquiries during a contention phase, and then the actual data is transferred using dynamic TDMA with first-come first-served. The channel encoding process in GPRS consists of two steps: first, a cyclic code is used to add parity bits, which are also referred to as the Block Check Sequence, followed by coding with a possibly punctured convolutional code . The Coding Schemes CS-1 to CS-4 specify

1953-410: Is used, an SMS transmission speed of about 30 SMS messages per minute may be achieved. This is much faster than using the ordinary SMS over GSM, whose SMS transmission speed is about 6 to 10 SMS messages per minute. As the GPRS standard is an extension of GSM capabilities, the service operates on the 2G and 3G cellular communication GSM frequencies. GPRS devices can typically use (one or more) of

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2016-482: The Uplink and Downlink directions. It is a value between 1 and 45 which the network uses to allocate radio channels in the uplink and downlink direction. Multislot class with values greater than 31 are referred to as high multislot classes. A multislot allocation is represented as, for example, 5+2. The first number is the number of downlink timeslots and the second is the number of uplink timeslots allocated for use by

2079-443: The 20th and 21st centuries. Some style guides do not recognize the different meanings of the term and simply recommend the form that best suits the target audience of the guide. For example, APA style as of the 7th edition requires "data" to be treated as a plural form. Data, information , knowledge , and wisdom are closely related concepts, but each has its role concerning the other, and each term has its meaning. According to

2142-599: 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

2205-502: 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. HSCSD was specified in 1997. Nokia 6210 was the first mobile phone from Nokia that supported HSCSD. GSM data transmission has advanced since

2268-447: The act of observation as constitutive, is offered as an alternative to data for visual representations in the humanities. The term data-driven is a neologism applied to an activity which is primarily compelled by data over all other factors. Data-driven applications include data-driven programming and data-driven journalism . General Packet Radio Service General Packet Radio Service ( GPRS ), also called 2.5G ,

2331-462: The active round-trip time can be reduced, resulting in significant increase in application-level throughput speeds. GSM was designed for voice, not data. It did not provide direct access to the Internet and it had a limited capacity of 9600 bauds per second. The limitations of Circuit Switched Data (CSD) also included higher costs. GPRS opened in 2000 as a packet-switched data service embedded in

2394-433: The best method to climb it. Awareness of the characteristics represented by this data is knowledge. Data are often assumed to be the least abstract concept, information the next least, and knowledge the most abstract. In this view, data becomes information by interpretation; e.g., the height of Mount Everest is generally considered "data", a book on Mount Everest geological characteristics may be considered "information", and

2457-434: The binary alphabet. Some special forms of data are distinguished. A computer program is a collection of data, that can be interpreted as instructions. Most computer languages make a distinction between programs and the other data on which programs operate, but in some languages, notably Lisp and similar languages, programs are essentially indistinguishable from other data. It is also useful to distinguish metadata , that is,

2520-476: The channel-switched cellular radio network GSM . GPRS extends the reach of the fixed Internet by connecting mobile terminals worldwide. The CELLPAC protocol developed 1991–1993 was the trigger point for starting in 1993 the specification of standard GPRS by ETSI SMG . Especially, the CELLPAC Voice & Data functions introduced in a 1993 ETSI Workshop contribution anticipate what was later known to be

2583-617: The concept of a sign to differentiate between data and information; data is a series of symbols, while information occurs when the symbols are used to refer to something. Before the development of computing devices and machines, people had to manually collect data and impose patterns on it. With the development of computing devices and machines, these devices can also collect data. In the 2010s, computers were widely used in many fields to collect data and sort or process it, in disciplines ranging from marketing , analysis of social service usage by citizens to scientific research. These patterns in

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2646-444: The course of a controlled scientific experiment. Data are analyzed using techniques such as calculation , reasoning , discussion, presentation , visualization , or other forms of post-analysis. Prior to analysis, raw data (or unprocessed data) is typically cleaned: Outliers are removed, and obvious instrument or data entry errors are corrected. Data can be seen as the smallest units of factual information that can be used as

2709-408: The data are seen as information that can be used to enhance knowledge. These patterns may be interpreted as " truth " (though "truth" can be a subjective concept) and may be authorized as aesthetic and ethical criteria in some disciplines or cultures. Events that leave behind perceivable physical or virtual remains can be traced back through data. Marks are no longer considered data once the link between

2772-575: The ethos of data as "given". Peter Checkland introduced the term capta (from the Latin capere , "to take") to distinguish between an immense number of possible data and a sub-set of them, to which attention is oriented. Johanna Drucker has argued that since the humanities affirm knowledge production as "situated, partial, and constitutive," using data may introduce assumptions that are counterproductive, for example that phenomena are discrete or are observer-independent. The term capta , which emphasizes

2835-419: 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

2898-583: 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

2961-800: The frequencies within one of the frequency bands the radio supports (850, 900, 1800, 1900 MHz). Depending on the device, location and intended use, regulations may be imposed either restricting or explicitly specifying authorised frequency bands. GSM-850 and GSM-1900 are used in the United States, Canada, and many other countries in the Americas. GSM-900 and GSM-1800 are used in: Europe, Middle East, Africa and most of Asia. In South Americas these bands are used in Costa Rica (GSM-1800), Brazil (GSM-850, 900 and 1800), Guatemala (GSM-850, GSM-900 and 1900), El Salvador (GSM-850, GSM-900 and 1900). There

3024-589: The introduction of CSD: In some places CSD services have continued to operate on 2G networks for a long time. In the Netherlands operator KPN switched the service off in 2021. Data Data are collected using techniques such as measurement , observation , query , or analysis , and are typically represented as numbers or characters that may be further processed . Field data are data that are collected in an uncontrolled, in-situ environment. Experimental data are data that are generated in

3087-466: 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

3150-538: The mark and observation is broken. Mechanical computing devices are classified according to how they represent data. An analog computer represents a datum as a voltage, distance, position, or other physical quantity. A digital computer represents a piece of data as a sequence of symbols drawn from a fixed alphabet . The most common digital computers use a binary alphabet, that is, an alphabet of two characters typically denoted "0" and "1". More familiar representations, such as numbers or letters, are then constructed from

3213-651: The mobile station. A commonly used value is class 10 for many GPRS/EGPRS mobiles which uses a maximum of 4 timeslots in downlink direction and 2 timeslots in uplink direction. However simultaneously a maximum number of 5 simultaneous timeslots can be used in both uplink and downlink. The network will automatically configure for either 3+2 or 4+1 operation depending on the nature of data transfer. Some high end mobiles, usually also supporting UMTS , also support GPRS/ EDGE multislot class 32. According to 3GPP TS 45.002 (Release 12), Table B.1, mobile stations of this class support 5 timeslots in downlink and 3 timeslots in uplink with

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3276-404: The number of parity bits generated by the cyclic code and the puncturing rate of the convolutional code. In Coding Schemes CS-1 through CS-3, the convolutional code is of rate 1/2, i.e. each input bit is converted into two coded bits. In Coding Schemes CS-2 and CS-3, the output of the convolutional code is punctured to achieve the desired code rate. In Coding Scheme CS-4, no convolutional coding

3339-425: The older CSD - and uses unused time-division multiple access (TDMA) channels in the GSM system for efficiency. GPRS is a best-effort service , implying variable throughput and latency that depend on the number of other users sharing the service concurrently, as opposed to circuit switching , where a certain quality of service (QoS) is guaranteed during the connection. Unlike older circuit switching data, GPRS

3402-522: The petabyte scale. Using traditional data analysis methods and computing, working with such large (and growing) datasets is difficult, even impossible. (Theoretically speaking, infinite data would yield infinite information, which would render extracting insights or intelligence impossible.) In response, the relatively new field of data science uses machine learning (and other artificial intelligence (AI)) methods that allow for efficient applications of analytic methods to big data. The Latin word data

3465-405: The problem of reproducibility is the attempt to require FAIR data , that is, data that is Findable, Accessible, Interoperable, and Reusable. Data that fulfills these requirements can be used in subsequent research and thus advances science and technology. Although data is also increasingly used in other fields, it has been suggested that the highly interpretive nature of them might be at odds with

3528-452: The requested data. Overall, the likelihood of retrieving data dropped by 17% each year after publication. Similarly, a survey of 100 datasets in Dryad found that more than half lacked the details to reproduce the research results from these studies. This shows the dire situation of access to scientific data that is not published or does not have enough details to be reproduced. A solution to

3591-457: The research's objectivity and permit an understanding of the phenomena under investigation as complete as possible: qualitative and quantitative methods, literature reviews (including scholarly articles), interviews with experts, and computer simulation. The data is thereafter "percolated" using a series of pre-determined steps so as to extract the most relevant information. An important field in computer science , technology , and library science

3654-597: The roots of GPRS. This workshop contribution is referenced in 22 GPRS-related US patents. Successor systems to GSM/GPRS like W-CDMA ( UMTS ) and LTE rely on key GPRS functions for mobile Internet access as introduced by CELLPAC. According to a study on history of GPRS development, Bernhard Walke and his student Peter Decker are the inventors of GPRS — the first system providing worldwide mobile Internet access. Enhanced Data rates for GSM Evolution (EDGE), also known as 2.75G, Enhanced GPRS (EGPRS), IMT Single Carrier (IMT-SC), and Enhanced Data rates for Global Evolution,

3717-412: The shared nature of GPRS, these instead establish a dedicated circuit (usually billed per minute). Some applications such as video calling may prefer HSCSD, especially when there is a continuous flow of data between the endpoints. The following table summarises some possible configurations of GPRS and circuit switched data services. The multislot class determines the speed of data transfer available in

3780-474: The synthesis of data into information, can then be described as knowledge . Data has been described as "the new oil of the digital economy ". Data, as a general concept , refers to the fact that some existing information or knowledge is represented or coded in some form suitable for better usage or processing . Advances in computing technologies have led to the advent of big data , which usually refers to very large quantities of data, usually at

3843-407: 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

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3906-539: Was similar to a modem connection in an analog wire telephone network, about 32–40 kbit/s, depending on the phone used. Latency is very high; round-trip time (RTT) is typically about 600–700 ms and often reaches 1s. GPRS is typically prioritized lower than speech, and thus the quality of connection varies greatly. Devices with latency/RTT improvements (via, for example, the extended UL TBF mode feature) are generally available. Also, network upgrades of features are available with certain operators. With these enhancements

3969-415: Was sold according to the total volume of data transferred instead of time spent online, which is now standard. GPRS was succeeded by EDGE (2.75G) which provided improved performance. GPRS was established by European Telecommunications Standards Institute (ETSI) in response to the earlier CDPD and i-mode packet-switched cellular technologies and is integrated into GSM Release 97 and newer releases. It

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