Journal articles on the topic 'Wireless network z-wave'

In this paper, will be presented actual research of the intelligent channel allocation. The intelligent channel allocation is based on combination of fuzzy logic method and game theory attributes to increase quality of link in network. The channel allocations will become an important phenomenon in different types of networks such as 5G technology, wireless networks (IEEE 802.11xx), Z-Wave, LoRa, 3G, 4G, etc. In the near future, new network technologies, Internet of Things (IoT) and Smart Cities will need to have intelligent channel allocation to prevent interference on the channels used for data transfer. These networks along with IoT are considered as promising technology, that interconnects different types of networks into one fully functional network. The aim of this paper is to present the concept of a methods for channel allocation in wireless networks, where channels work as communication medium based on IEEE 802.11xx technology. The simulations prove, that proposed method is able to provide lower interference, improve data rates and increase quality of links.

Abstract. A Network model of an ultra-wide band, intra-chip wireless link is presented. Numerical data of Z-parameters, obtained from full wave simulation of the structure, are used to obtain a rational function representation via the Vector Fitting procedure. Brune's circuit synthesis is applied to generate the network model from rational functions.

A remote control system for smart home is designed based on Z-wave, which is divided into two components: controller and receiver. In the controller design, the key signals are scanned by SCM P89LPC9408 to generate and transmit different control commands to Z-wave module, and then the relative commands are packed by Z-wave protocol and transmitted from a wireless network, LCD module is used to display the relative information such as time and temperature. In the receiver design, the Z-wave signal is received by receive module, and the transmission commands are demodulated and transmitted to SCM P89LPC938 to realize the relative functions. The results show that this system has a certain application value for smart home design.

The advent of technology with the increasing use of wireless network has led to the development of Wireless Body Area Network (WBAN) to continuously monitor the change of physiological data in a cost efficient manner. As numerous researches on wave propagation characterization have been done in intrabody communication, this study has given emphasis on the wave propagation characterization between the control units (CUs) and wireless access point (AP) in a hospital scenario. Ray tracing is a tool to predict the rays to characterize the wave propagation. It takes huge simulation time, especially when multiple transmitters are involved to transmit physiological data in a realistic hospital environment. Therefore, this study has developed an accelerated ray tracing method based on the nearest neighbor cell and prior knowledge of intersection techniques. Beside this, Red-Black tree is used to store and provide a faster retrieval mechanism of objects in the hospital environment. To prove the superiority, detailed complexity analysis and calculations of reflection and transmission coefficients are also presented in this paper. The results show that the proposed method is about 1.51, 2.1, and 2.9 times faster than the Object Distribution Technique (ODT), Space Volumetric Partitioning (SVP), and Angular Z-Buffer (AZB) methods, respectively. To show the various effects on received power in 60 GHz frequency, few comparisons are made and it is found that on average −9.44 dBm, −8.23 dBm, and −9.27 dBm received power attenuations should be considered when human, AP, and CU move in a given hospital scenario.

Single-phase Z-type strontium cobalt hexaferrite was prepared by polymerizable complex method. Magnetic properties and dynamic magnetic response for high frequency of the Z-type ferrite were studied. Single-phase Z-type hexaferrite was obtained by heating at 1473K for 5 hours in air. Phase identification and determination of lattice parameters were carried out by powder X-ray diffraction (XRD). Magnetic properties were discussed by measuring of M-H curve with vibrating sample magnetometer (VSM). The complex permeability and permittivity over 0.2-18GHz were measured using a vector network analyzer with transmission-reflection-line (TRL) calibration. The results show that the single-phase Z-type strontium cobalt hexaferrite prepared in this study is one of potential candidates for use as electromagnetic wave absorbing materials in the frequency range 1-3GHz (for hand-held cellular phone and wireless LAN).

<p>Wireless sensor networks (WSN), referring to groups of technologies wirelessly controlled, are widely used in many different fields, agriculture, medical, military, etc. These technologies are mainly used for monitoring physical or environmental conditions, such as temperatures, sound, pressure, and so on. In WSN fields, there are technologies as Wi-Fi, radio frequency (RF), Bluetooth, ZigBee, Z-Wave, and so on. Furthermore, there is one of this technology that offers more outstanding futures to provide more energy-saving and long distances of transmissions compared to other technologies, and that is Zigbee technology, and this had become for many applications, the first high-quality to use and consequently the most used in WSNs. In Zigbee aided WSNs, are included three main devices used to communicate data, that is a Zig-Bee coordinator (network coordinator), ZigBee router, and ZigBee end-devices. The data sensed is transmitted from sensor nodes through coordinators to a base-station (BS), this device (coordinator), collects the data, stores it in a memory, processes, and finally forward to the next suitable nodes or the BS. This research presents the concepts and discussions of Zigbee technologies used in WSNs. Utmost ZigBee communication technologies are revised and analyzed, as well as simulation results with different scenarios are addressed comprehensively. Proposals for advance applications in WSNs are presented. Suggestions for future developments are provided</p>

Schools are amongst the most densely occupied indoor areas and at the same time children and young adults are the most vulnerable group with respect to adverse health effects as a result of poor environmental conditions. Health, performance and well-being of pupils crucially depend on indoor environmental quality (IEQ) of which air quality and thermal comfort are central pillars. This makes the monitoring and control of environmental parameters in classes important. At the same time most school buildings do neither feature automated, intelligent heating, ventilation, and air conditioning (HVAC) systems nor suitable IEQ monitoring systems. In this contribution, we therefore investigate the capabilities of a novel wireless gas sensor network to determine carbon dioxide concentrations, along with temperature and humidity. The use of a photoacoustic detector enables the construction of long-term stable, miniaturized, LED-based non-dispersive infrared absorption spectrometers without the use of a reference channel. The data of the sensor nodes is transmitted via a Z-Wave protocol to a central gateway, which in turn sends the data to a web-based platform for online analysis. The results show that it is difficult to maintain adequate IEQ levels in class rooms even when ventilating frequently and that individual monitoring and control of rooms is necessary to combine energy savings and good IEQ.

This article presents research results on a smart building prediction, navigation and asset management system. The main goal of this work was to combine all comfort subsystems, such as lighting, heating or air conditioning control, into one coherent management system supported by navigation using radio tomographic imaging techniques and computational intelligence in order to improve the building’s ability to track users and then maximize the energy efficiency of the building by analyzing their behavior. In addition, the data obtained in this way were used to increase the quality of navigation services, improve the safety and ergonomics of using the room access control system and create a centralized control panel enriched with records of the working time of individual people. The quality of the building’s user habit learning is ensured by a network of sensors collecting environmental data and thus the setting values of the comfort modules. The advantage of such a complex solution is an increase in the accuracy of navigation services provided, an improvement in the energy balance, an improvement in the level of safety and faster facility diagnostics. The solution uses proprietary small device assemblies with implementation of popular wireless transmission standards such as Bluetooth, Wi-Fi, ZigBee or Z-Wave. These PANs (personal area networks) are used to update and transmit environmental and navigation data (Bluetooth), to maintain the connection of other PANs to the master server (Wi-Fi) and to communicate with specific end devices (ZigBee and Z-Wave).

Protocol stacks specifically designed for the Internet of Things (IoT) have become commonplace. At the same time, security and privacy concerns regarding IoT technologies are also attracting significant attention given the risks that are inherently associated with the respective devices and their numerous applications, ranging from healthcare, smart homes, and cities, to intelligent transportation systems and industrial automation. Considering the still heterogeneous nature of the majority of IoT protocols, a major concern is to find common references for investigating and analyzing their security and privacy threats. To this end, and on top of the current literature, this work provides a comprehensive, vis-à-vis comparison of the security aspects of the thus far most widespread IoT Wireless Personal Area Network (WPAN) protocols, namely BLE, Z-Wave, ZigBee, Thread, and EnOcean. A succinct but exhaustive review of the relevant literature from 2013 up to now is offered as a side contribution.

The devices of IoT use the wide spectrum of wireless technologies today. Here technologies of short radius enter actions that use the unlicensed spectrum usually, for example WiFi, Bluetooth, ZigBee and Z - wave, and also technologies of wide cellular, that use the licensed spectrum, for example GSM, LTE and 5G. Also accessible alternative decisions, such as technologies of small-yield, that work in the unlicensed spectrum, in particular LoRa and Sigfox. Last years a mobile traffic grows confidently, and this trend will be saved in the near time. According to different prognoses, after 2024 the amount of traffic that is processed by mobile communication networks will exceed present indexes more than in 100 times. There is of interest consideration of effective methods of management a traffic, related to the choice of radiotechnology both on the side of subscriber terminal, and directly by an infrastructural cellular network. As a result, a transfer of effective data rate rises and goes down amplitude of her vibrations, and middle spectral efficiency is kept here at acceptable level. Self on itself off-wire co-operation «device - a device» is the important mode of functioning of the system not only for the transmission of mobile traffic in perspective networks, traditional users oriented to service but also for providing of wide circle of scenarios that arise up during realization of міжмашинної co-operation within the framework of conception of the Internet of things.

This article discusses the problems of information security in "SmartCity" systems. The comparison of existing solutions and data protocols for wired solutions, such as IPsec, SSL, TLS and wireless systems: ZigBee, Z-Wave, Thread, WeMo. The advantages and disadvantages of each of the existing systems are analyzed. The SmartCity system must be able to recognize a specific situation that arises in the house, city, workplace, when processing large amounts of data, to respond accordingly: one of the systems can control the behavior of other systems using a pre-designed algorithm. The main purpose of the "SmartCity" system is to save energy, which is becoming increasingly important due to their rise in price in Ukraine. Therefore, intellectualization is becoming increasingly popular, catching up with global trends in home automation. However, despite the development and gradual formal and informal standardization of smart city technologies, and any home automation, there is still the problem of choosing protocols for the transfer of information between controlled devices, sensors and other elements. This problem is especially serious when it is necessary to ensure the confidentiality and integrity of data circulating in the system. The purpose of this study is to find a secure network protocol that allows you to use it in automatic signaling equipment, so you can not use special software and hardware solutions to affect the confidentiality and integrity of information.In the article is not the last issue of information security such a house of the city government system or production, can cause very great damage to its owner. As remote management and access to information are quite common nowadays, secure schemes, encryption and protection schemes should be used to reduce the percentage of vulnerabilities and prevent intruders from causing harm.

A new IoT authentication protocol is presented to address the security deficiencies in the Z-Wave protocol. The new protocol is based on Diameter and includes authentication/authorization module, billing module, and secure communication module. According to the characteristics of IoT devices, the relevant algorithms are optimized, and the key agreement scheme based on elliptic curve algorithm and the symmetric encryption scheme based on AES and RC4 are introduced, which enhances the security of the protocol and also improves the system performance. The speed of response reduces the energy consumption of the system. Aiming at solving the problem that the existing polynomial-based key predistribution management scheme is limited by the key sharing rate between the nodes and the network connectivity rate, a quadratic-based wireless sensor key management scheme is proposed. The scheme breaks through the existing idea of building a shared key with a binary t-order symmetric polynomial, introduces a multivariate asymmetric quadratic polynomial, and utilizes the relationship between the quadratic eigenvalues and eigenvectors. The analysis proves that the quadratic form can be orthogonally diagonalized and uses it to generate key information, and nodes realize identity authentication by exchanging key information. The establishment of an independent and unique session key with the neighbor node is completed. The security performance analysis and simulation results show that, compared with the existing key management schemes, the scheme has great improvements in anti-capture property, connectivity, scalability, communication overhead, and storage overhead. After a series of functional tests, the enterprise information system based on the SaaS platform in this paper basically met the design requirements and finally realized the networking of the enterprise information management process and the sharing of information. Each functional module of the system can be used normally. When the input and output are wrong, the system will have a correct prompt. The buttons and various controls of the system can work normally, meeting the requirements of functional testing. Each document of the system is correct and complete, and the language description and logic meet the needs of users and meet the requirements of document testing. The test results show that the interface of the system is friendly and easy to operate and the performance of the system is stable, which is basically in line with the needs of users and achieves the design goal of this system.

Ready-made solutions for building the network infrastructure of the «Smart Home» system are analyzed, their advantages and disadvantages are revealed. The article discusses in detail the use of Z-Wave technology in building a network for «Smart Home». The plan of building a new network infrastructure is formulated. Based on the analysis, a network infrastructure was developed for the Smart Home system using Z-Wave technology. Z-Wave was introduced to the market in 2003 by Zensys, acquired five years later by Sigma Designs, which now licenses the technology and remains a major supplier of Z-Wave chips. Addressing all the critical needs of the emerging smart home segment, it has become a leading international wireless standard for residential automation management and automation. To date, there are more than 1300 certified devices on the market and around 35 million compatible units are mature and proven technology. Simple Z-Wave covers all layers of the core OSI model for network communications, from the physical layer to the application layer. Unlike the vast majority of the leading wireless solutions, the protocol provides full compatibility between the various branded products based on it. This would be impossible without determining the level of applications, but also without the clear standard and certification programs installed by Z-Wave Alliance. Z-Wave was designed to allow individual nodes to send messages until they reach their final destination. Extending the range of the wireless network significantly, even today, networks are considered essential to providing reliable coverage in building automation. First of all, the Z-Wave network is capable of sending messages through up to 4 repetitive nodes. This alone limits potential applications in a smart home environment, as commercial and office space often require wider network coverage.

Currently, with the advent of smart devices, our life has become more convenient – it is now easier to do household chores, track the movement of goods, etc. The development of smart devices with the advent of new wireless communication standards helped to give impulse to the unification of smart gadgets into a network, which is often used in smart homes. With this approach, there are some security problems, such as unauthorized access to devices by third parties, interference with the operation of devices, failure of routers, limiting the radius of data transfer between devices, reducing the bandwidth of devices with increasing distance between the gadget and the router, etc. This article talks about IoT technology and how I use it for home automation. The modern view of building wireless home automation networks, which allows you to solve some of these problems, involves a decentralized approach, for example, the usage of mesh-network. This article describes how mesh networking works, and lists the benefits of using it in home automation. When using mesh networking technologies such as Z-Wave or Zigbee, it is possible to link multiple devices into a «seamless» network using Bluetooth or Wi-Fi. The authors reviewed the most popular technologies that use mesh network topology for home automation. These technologies increase the throughput of devices several times. It also allows you to protect devices from third-party intrusion into the system by assigning unique private keys to each device of the network, which decrypts only those packets that are intended for this device.

Background: The smart grid communication network is constructed with three tiers namely, Home Area Networks (HANs), Neighborhood Area Networks (NANs) and Wide Area Networks (WANs). These networks function with various communication protocols like table protocol, on-demand protocol, Wi-Fi, Zigbee, Z-Wave, Wi-MAX, GSM, LTE, Cognitive Radio Networks. The network interconnection is heterogonous and all appliances have to communicate through the IP gateways. A large amount of data is collected from various sensors placed in different locations. The analytics on large data- “big data” is essential because these data were used to organize and plan an efficient control and management of the smart home including secured data exchange in different sectors. Objective: This paper investigates broadly on data rate, channel bandwidth, power consumption, and a coverage range of both wired and wireless communication technologies used in residential buildings. Besides, a literature survey on optimization algorithms with various constraints to manage home appliances through scheduling is included. The paper also discusses the communication standards along with security and privacy requirements for smart metering networks. Conclusion: Discussion on IEEE standards for both wired and wireless communication protocols. Gives direction to identify the suitable communication technique through mathematical model for computing the communication channel bandwidth. Comparison of various optimization algorithms with multiple constraints in HEMS to achieve the minimum electricity cost and user comfort (with and without Renewable Energy Sources). From the investigation on both wired and wireless networks, the wireless communication networks (Zig-Bee & Wi-Fi) are mostly preferred to use in HAN because of more reliability and low cost. Zigbee is the most appropriate technology used for data transmission between the individual appliances and smart meters. Wi-Fi is a suitable technology for controlling and monitoring appliances because of its high data rate.

In this paper, we analyze an underlay two-way decode-and-forward scheme in which secondary relays use successive interference cancellation (SIC) technology to decode data of two secondary sources sequentially, and then generate a coded signal by superposition coding (SC) technology, denoted as SIC-SC protocol. The SIC-SC protocol is designed to operate in two time slots under effects from an interference constraint of a primary receiver and residual interference of imperfect SIC processes. Transmit powers provided to carry the data are allocated dynamically according to channel powers of interference and transmission, and a secondary relay is selected from considering strongest channel gain subject to increase in decoding capacity of the first data and decrease in collection time of channel state information. Closed-form outage probability expressions are derived from mathematical manipulations and verified by performing Monte Carlo simulations. An identical scheme of underlay two-way decodeand-forward relaying with random relay selection and fixed power allocations is considered to compare with the proposed SIC-SC protocol, denoted as RRS protocol. Simulation and analysis results show that the non-identical outage performances of the secondary sources in the proposed SIC-SC protocol are improved by increasing the number of the secondary relays and the interference constraint as well as decreasing the residual interference powers. Secondly, the performance of the nearer secondary source is worse than that of the farther secondary source. In addition, the proposed SIC-SC protocol outperforms the RRS comparison protocol, and effect of power allocations through channel powers is discovered. Finally, derived theory values are precise to simulation results. Keywords: Successive interference cancellation, superposition coding, power allocation, underlay cognitive radio, non-orthogonal multiple access, outage probability. 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Mobile In many countries, more people have mobile phones than they do fixed-line phones. Mobile phones are one of the fastest growing technologies ever, outstripping even the internet in many respects. With the advent and widespread deployment of digital systems, mobile phones were used by an estimated 1, 158, 254, 300 people worldwide in 2002 (up from approximately 91 million in 1995), 51. 4% of total telephone subscribers (ITU). One of the reasons for this is mobility itself: the ability for people to talk on the phone wherever they are. The communicative possibilities opened up by mobile phones have produced new uses and new discourses (see Katz and Aakhus; Brown, Green, and Harper; and Plant). Contemporary soundscapes now feature not only voice calls in previously quiet public spaces such as buses or restaurants but also the aural irruptions of customised polyphonic ringtones identifying whose phone is ringing by the tune downloaded. The mobile phone plays an important role in contemporary visual and material culture as fashion item and status symbol. Most tragically one might point to the tableau of people in the twin towers of the World Trade Centre, or aboard a plane about to crash, calling their loved ones to say good-bye (Galvin). By contrast, one can look on at the bathos of Australian cricketer Shane Warne’s predilection for pressing his mobile phone into service to arrange wanted and unwanted assignations while on tour. In this article, I wish to consider another important and so far also under-theorised aspect of mobile phones: text. Of contemporary textual and semiotic systems, mobile text is only a recent addition. Yet it is already produces millions of inscriptions each day, and promises to be of far-reaching significance. Txt Txt msg ws an acidnt. no 1 expcted it. Whn the 1st txt msg ws sent, in 1993 by Nokia eng stdnt Riku Pihkonen, the telcom cpnies thought it ws nt important. SMS – Short Message Service – ws nt considrd a majr pt of GSM. Like mny teks, the *pwr* of txt — indeed, the *pwr* of the fon — wz discvrd by users. In the case of txt mssng, the usrs were the yng or poor in the W and E. (Agar 105) As Jon Agar suggests in Constant Touch, textual communication through mobile phone was an after-thought. Mobile phones use radio waves, operating on a cellular system. The first such mobile service went live in Chicago in December 1978, in Sweden in 1981, in January 1985 in the United Kingdom (Agar), and in the mid-1980s in Australia. Mobile cellular systems allowed efficient sharing of scarce spectrum, improvements in handsets and quality, drawing on advances in science and engineering. In the first instance, technology designers, manufacturers, and mobile phone companies had been preoccupied with transferring telephone capabilities and culture to the mobile phone platform. With the growth in data communications from the 1960s onwards, consideration had been given to data capabilities of mobile phone. One difficulty, however, had been the poor quality and slow transfer rates of data communications over mobile networks, especially with first-generation analogue and early second-generation digital mobile phones. As the internet was widely and wildly adopted in the early to mid-1990s, mobile phone proponents looked at mimicking internet and online data services possibilities on their hand-held devices. What could work on a computer screen, it was thought, could be reinvented in miniature for the mobile phone — and hence much money was invested into the wireless access protocol (or WAP), which spectacularly flopped. The future of mobiles as a material support for text culture was not to lie, at first at least, in aping the world-wide web for the phone. It came from an unexpected direction: cheap, simple letters, spelling out short messages with strange new ellipses. SMS was built into the European Global System for Mobile (GSM) standard as an insignificant, additional capability. A number of telecommunications manufacturers thought so little of the SMS as not to not design or even offer the equipment needed (the servers, for instance) for the distribution of the messages. The character sets were limited, the keyboards small, the typeface displays rudimentary, and there was no acknowledgement that messages were actually received by the recipient. Yet SMS was cheap, and it offered one-to-one, or one-to-many, text communications that could be read at leisure, or more often, immediately. SMS was avidly taken up by young people, forming a new culture of media use. Sending a text message offered a relatively cheap and affordable alternative to the still expensive timed calls of voice mobile. In its early beginnings, mobile text can be seen as a subcultural activity. The text culture featured compressed, cryptic messages, with users devising their own abbreviations and grammar. One of the reasons young people took to texting was a tactic of consolidating and shaping their own shared culture, in distinction from the general culture dominated by their parents and other adults. Mobile texting become involved in a wider reworking of youth culture, involving other new media forms and technologies, and cultural developments (Butcher and Thomas). Another subculture that also was in the vanguard of SMS was the Deaf ‘community’. Though the Alexander Graham Bell, celebrated as the inventor of the telephone, very much had his hearing-impaired wife in mind in devising a new form of communication, Deaf people have been systematically left off the telecommunications network since this time. Deaf people pioneered an earlier form of text communications based on the Baudot standard, used for telex communications. Known as teletypewriter (TTY), or telecommunications device for the Deaf (TDD) in the US, this technology allowed Deaf people to communicate with each other by connecting such devices to the phone network. The addition of a relay service (established in Australia in the mid-1990s after much government resistance) allows Deaf people to communicate with hearing people without TTYs (Goggin & Newell). Connecting TTYs to mobile phones have been a vexed issue, however, because the digital phone network in Australia does not allow compatibility. For this reason, and because of other features, Deaf people have become avid users of SMS (Harper). An especially favoured device in Europe has been the Nokia Communicator, with its hinged keyboard. The move from a ‘restricted’, ‘subcultural’ economy to a ‘general’ economy sees mobile texting become incorporated in the semiotic texture and prosaic practices of everyday life. Many users were already familiar with the new conventions already developed around electronic mail, with shorter, crisper messages sent and received — more conversation-like than other correspondence. Unlike phone calls, email is asynchronous. The sender can respond immediately, and the reply will be received with seconds. However, they can also choose to reply at their leisure. Similarly, for the adept user, SMS offers considerable advantages over voice communications, because it makes textual production mobile. Writing and reading can take place wherever a mobile phone can be turned on: in the street, on the train, in the club, in the lecture theatre, in bed. The body writes differently too. Writing with a pen takes a finger and thumb. Typing on a keyboard requires between two and ten fingers. The mobile phone uses the ‘fifth finger’ — the thumb. Always too early, and too late, to speculate on contemporary culture (Morris), it is worth analyzing the textuality of mobile text. Theorists of media, especially television, have insisted on understanding the specific textual modes of different cultural forms. We are familiar with this imperative, and other methods of making visible and decentring structures of text, and the institutions which animate and frame them (whether author or producer; reader or audience; the cultural expectations encoded in genre; the inscriptions in technology). In formal terms, mobile text can be described as involving elision, great compression, and open-endedness. Its channels of communication physically constrain the composition of a very long single text message. Imagine sending James Joyce’s Finnegan’s Wake in one text message. How long would it take to key in this exemplar of the disintegration of the cultural form of the novel? How long would it take to read? How would one navigate the text? Imagine sending the Courier-Mail or Financial Review newspaper over a series of text messages? The concept of the ‘news’, with all its cultural baggage, is being reconfigured by mobile text — more along the lines of the older technology of the telegraph, perhaps: a few words suffices to signify what is important. Mobile textuality, then, involves a radical fragmentation and unpredictable seriality of text lexia (Barthes). Sometimes a mobile text looks singular: saying ‘yes’ or ‘no’, or sending your name and ID number to obtain your high school or university results. Yet, like a telephone conversation, or any text perhaps, its structure is always predicated upon, and haunted by, the other. Its imagined reader always has a mobile phone too, little time, no fixed address (except that hailed by the network’s radio transmitter), and a finger poised to respond. Mobile text has structure and channels. Yet, like all text, our reading and writing of it reworks those fixities and makes destabilizes our ‘clear’ communication. After all, mobile textuality has a set of new pre-conditions and fragilities. It introduces new sorts of ‘noise’ to signal problems to annoy those theorists cleaving to the Shannon and Weaver linear model of communication; signals often drop out; there is a network confirmation (and message displayed) that text messages have been sent, but no system guarantee that they have been received. Our friend or service provider might text us back, but how do we know that they got our text message? Commodity We are familiar now with the pleasures of mobile text, the smile of alerting a friend to our arrival, celebrating good news, jilting a lover, making a threat, firing a worker, flirting and picking-up. Text culture has a new vector of mobility, invented by its users, but now coveted and commodified by businesses who did not see it coming in the first place. Nimble in its keystrokes, rich in expressivity and cultural invention, but relatively rudimentary in its technical characteristics, mobile text culture has finally registered in the boardrooms of communications companies. Not only is SMS the preferred medium of mobile phone users to keep in touch with each other, SMS has insinuated itself into previously separate communication industries arenas. In 2002-2003 SMS became firmly established in television broadcasting. Finally, interactive television had arrived after many years of prototyping and being heralded. The keenly awaited back-channel for television arrives courtesy not of cable or satellite television, nor an extra fixed-phone line. It’s the mobile phone, stupid! Big Brother was not only a watershed in reality television, but also in convergent media. Less obvious perhaps than supplementary viewing, or biographies, or chat on Big Brother websites around the world was the use of SMS for voting. SMS is now routinely used by mainstream television channels for viewer feedback, contest entry, and program information. As well as its widespread deployment in broadcasting, mobile text culture has been the language of prosaic, everyday transactions. Slipping into a café at Bronte Beach in Sydney, why not pay your parking meter via SMS? You’ll even receive a warning when your time is up. The mobile is becoming the ‘electronic purse’, with SMS providing its syntax and sentences. The belated ingenuity of those fascinated by the economics of mobile text has also coincided with a technological reworking of its possibilities, with new implications for its semiotic possibilities. Multimedia messaging (MMS) has now been deployed, on capable digital phones (an instance of what has been called 2.5 generation [G] digital phones) and third-generation networks. MMS allows images, video, and audio to be communicated. At one level, this sort of capability can be user-generated, as in the popularity of mobiles that take pictures and send these to other users. Television broadcasters are also interested in the capability to send video clips of favourite programs to viewers. Not content with the revenues raised from millions of standard-priced SMS, and now MMS transactions, commercial participants along the value chain are keenly awaiting the deployment of what is called ‘premium rate’ SMS and MMS services. These services will involve the delivery of desirable content via SMS and MMS, and be priced at a premium. Products and services are likely to include: one-to-one textchat; subscription services (content delivered on handset); multi-party text chat (such as chat rooms); adult entertainment services; multi-part messages (such as text communications plus downloads); download of video or ringtones. In August 2003, one text-chat service charged $4.40 for a pair of SMS. Pwr At the end of 2003, we have scarcely registered the textual practices and systems in mobile text, a culture that sprang up in the interstices of telecommunications. It may be urgent that we do think about the stakes here, as SMS is being extended and commodified. There are obvious and serious policy issues in premium rate SMS and MMS services, and questions concerning the political economy in which these are embedded. Yet there are cultural questions too, with intricate ramifications. How do we understand the effects of mobile textuality, rewriting the telephone book for this new cultural form (Ronell). What are the new genres emerging? And what are the implications for cultural practice and policy? Does it matter, for instance, that new MMS and 3rd generation mobile platforms are not being designed or offered with any-to-any capabilities in mind: allowing any user to upload and send multimedia communications to other any. True, as the example of SMS shows, the inventiveness of users is difficult to foresee and predict, and so new forms of mobile text may have all sorts of relationships with content and communication. However, there are worrying signs of these developing mobile circuits being programmed for narrow channels of retail purchase of cultural products rather than open-source, open-architecture, publicly usable nodes of connection. Works Cited Agar, Jon. Constant Touch: A Global History of the Mobile Phone. Cambridge: Icon, 2003. Barthes, Roland. S/Z. Trans. Richard Miller. New York: Hill & Wang, 1974. Brown, Barry, Green, Nicola, and Harper, Richard, eds. Wireless World: Social, Cultural, and Interactional Aspects of the Mobile Age. London: Springer Verlag, 2001. Butcher, Melissa, and Thomas, Mandy, eds. Ingenious: Emerging youth cultures in urban Australia. Melbourne: Pluto, 2003. 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On the Mobile: The Effects of Mobile Telephones on Social and Individual Life. < http://www.motorola.com/mot/documents/0,1028,296,00.pdf> accessed 5 October 2003. Ronell, Avital. The Telephone Book: Technology—schizophrenia—electric speech. Lincoln: U of Nebraska P, 1989. Citation reference for this article MLA Style Goggin, Gerard. "‘mobile text’" M/C: A Journal of Media and Culture <http://www.media-culture.org.au/0401/03-goggin.php>. APA Style Goggin, G. (2004, Jan 12). ‘mobile text’. M/C: A Journal of Media and Culture, 7, <http://www.media-culture.org.au/0401/03-goggin.php>