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Tie strengths in social networks are heterogeneous, with strong and weak ties playing different roles at the network and individual levels. Egocentric networks, networks of relationships around an individual, exhibit few strong ties and more weaker ties, as evidenced by electronic communication records. Mobile phone data has also revealed persistent individual differences within this pattern. However, the generality and driving mechanisms of social tie strength heterogeneity remain unclear. Here, we study tie strengths in egocentric networks across multiple datasets of interactions between millions of people during months to years. We find universality in tie strength distributions and their individual-level variation across communication modes, even in channels not reflecting offline social relationships. Via a simple model of egocentric network evolution, we show that the observed universality arises from the competition between cumulative advantage and random choice, two tie reinforcement mechanisms whose balance determines the diversity of tie strengths. Our results provide insight into the driving mechanisms of tie strength heterogeneity in social networks and have implications for the understanding of social network structure and individual behavior. Personal communication networks through mobile phones and online platforms can be characterized by patterns of tie strengths. The authors propose a model to explain driving mechanisms of emerging tie strength heterogeneity in social networks, observing similarity of patterns across various datasets. [ABSTRACT FROM AUTHOR]

The article discusses technological advances related to the telephone. Telephony has evolved through the merging of all of today's communication technologies into the field of telephones. The author discusses some of these technologies, including a service from Accessline that gives users one virtual telephone number that people can call in order to reach users of the service at any one of their actual telephone numbers. He also discusses the Apple iPhone cellular telephone, which offers Internet and e-mail access.

Device-to-device (D2D) communication has been recently proposed to mitigate the burden of base stations by leveraging the underutilized cellular spectrum resources, where high overall network throughput and D2D access rate are critical for its service performance and availability. In this paper, we study the resource allocation problem to push the limit of D2D communication underlaying cellular networks by allowing multiple D2D links to share resource with multiple cellular links. We propose FRESH, a full resource sharing scheme where each subchannel can be shared by a cellular link and an arbitrary number of D2D links. In particular, FRESH first divides the communication links into so-called full resource sharing sets such that, within each set, all D2D link members are able to reuse the whole allocated resources. Thereafter, it allocates a sum of spectrum resources to each obtained full resource sharing set. As compared with state-of-the-art schemes, FRESH provides fine-grained resource allocation, resulting in throughput improvements of up to one order of magnitude, and D2D access rate improvements of up to 5 times with a moderate node density (e.g., on the order of 1 user per 400 square meters). [ABSTRACT FROM AUTHOR]

This paper examines the analytical modeling of mobile phone subscribers' switching behavior among the four major mobile telecommunication network service providers in Nigeria, using primary data collected through questionnaire from the mobile-phone subscribers of three higher institutions in Lagos, Nigeria. Data collected through the questionnaire was collated and structured to suit the modeling framework of Markov chain process. The findings reveal that many subscribers still hold multiple SIMs of network providers, unlike other countries where people have embraced Mobile Number Portability (MNP), thereby compelling the network providers to improve their quality of services to retain existing subscribers and attract potential customers who will switch from other service providers. [ABSTRACT FROM AUTHOR]

Personalized systems that provide appropriate solutions and assistance to consumers have become popular worldwide. Nowadays, mobile users are not only capable of making phone calls, but also can install applications that deploy the existing technologies to provide a personalized services such as personalized restaurant recommender. The realization of the next generation of personalized systems for special need consumers will be a challenging task. For our research purpose, the personal special needs are defined as: (Religions, Cultures, Allergies, Health Condition, Diet, Preferences and Dislikes) needs that affect many aspects of a consumer life. In general there is no shortage of the restaurant apps available in the App Store, However, most of the existing applications have undertaken with the price and the location factors in mind. They show the same results regardless on the personal special needs of consumers. They are not a great choice for special needs consumers. We propose a novel "Personalized Mobile Restaurant" PMR system. To meet the strict needs of consumers; a requirement driven design approach was followed. Our system supported a load balance algorithm to avoid overloaded condition. The proposed system was tested by groups selected based on the small world criteria successfully and promising results were obtained. [ABSTRACT FROM AUTHOR]

Short Message Service (SMS) messages are short messages sent from one person to another from their mobile phones. They represent a means of personal communication that is an important communicative artifact in our current digital era. As most existing studies have used private access to SMS corpora, comparative studies using the same raw SMS data have not been possible up to now. We describe our efforts to collect a public SMS corpus to address this problem. We use a battery of methodologies to collect the corpus, paying particular attention to privacy issues to address contributors' concerns. Our live project collects new SMS message submissions, checks their quality, and adds valid messages. We release the resultant corpus as XML and as SQL dumps, along with monthly corpus statistics. We opportunistically collect as much metadata about the messages and their senders as possible, so as to enable different types of analyses. To date, we have collected more than 71,000 messages, focusing on English and Mandarin Chinese. [ABSTRACT FROM AUTHOR]

Background: Process evaluation is essential in developing, piloting and evaluating complex interventions. This often involves observation of intervention delivery and interviews with study participants. Mobile telephone interventions involve no face to face contact, making conventional process evaluation difficult. This study assesses the utility of novel techniques for process evaluation involving no face to face contact. Methods: Text messages were delivered to 34 disadvantaged men as part of a feasibility study of a brief alcohol intervention. Process evaluation focused on delivery of the text messages and responses received from study participants. The computerized delivery system captured data on receipt of the messages. The text messages, delivered over 28 days, included nine which asked questions. Responses to these questions served as one technique for process evaluation by ascertaining the nature of engagement with the study and with steps on the causal chain to behavior change. Results: A total of 646 SMS text messages were sent to participants. Of these, 613 messages (95%) were recorded as delivered to participants' telephones. 88% of participants responded to messages that asked questions. There was little attenuation in responses to the questions across the intervention period. Content analysis of the responses revealed that participants engaged with text messages, thought deeply about their content and provided carefully considered personal responses to the questions. Conclusions: Socially disadvantaged men, a hard to reach population, engaged in a meaningful way over a sustained period with an interactive intervention delivered by text message. The novel process measures used in the study are unobtrusive, low cost and collect real-time data on all participants. They assessed the fidelity of delivery of the intervention and monitored retention in the study. They measured levels of engagement and identified participants' reactions to components of the intervention. These methods provide a valuable addition to conventional process evaluation techniques. [ABSTRACT FROM AUTHOR]

The article focuses on the role of mobile phones in improving conjugal power relations in the context of mother-away Filipino American families. By taking interviews of 10 pairs of fathers and children from mother-away families, it is found that the mobile phone provides parents avenues to both expand and hold on to their traditionally gender-differentiated roles. It mitigates the complex relation between these fathers and mothers. It is focused that the mobile phones help to increase cooperation between left-behind fathers and migrant mothers and it has mostly resulted in exacerbating.

A number of key factors impact mobile phone use for personal agency in various settings, including non-conventional ways not thought of before even by the designers and creators of this technology. [ABSTRACT FROM AUTHOR]

In this study we analyzed the interaction between active seniors and mobile phone use. Results were obtained from a survey. Participants were 165 active seniors enrolled in university programs for seniors, most of whom owned a mobile phone and used it for basic functions such as making calls, creating a contact list, checking the time, and sending text messages. The mobile phone did not have a social expansion function (that is, to extend their social networks) for these people; but it did provide them with social support by allowing them to keep in touch with their relatives. It also made them feel secure, free, and independent. [ABSTRACT FROM AUTHOR]

Modern vehicular platforms include several wireless systems that provide navigation, entertainment and road side assistance, among other services. These systems operate at different frequency bands and thus careful system-level design should be followed to minimise the interference between them. In this study, we present a compact dual-band RF front-end module for global positioning system (GPS) operating in the L1-band (1574.42–1576.42 MHz) and satellite digital audio radio system (SDARS) operating in the S-band (2320–2345 MHz). The module provides more than 26 dB of measured gain in both bands and low noise figure values of 0.9 and 1.2 dB in SDARS and GPS bands, respectively. The front-end has interference suppression capability from the advanced mobile phone system and personal communication service cellular bands. The module is designed on a low-cost FR-4 substrate material and occupies a small size of 62 × 29 × 1.3 mm3. It dissipates 235 mW in the SDARS section and 100 mW in the GPS section. Three prototypes have been built to verify a repeatable performance. [ABSTRACT FROM PUBLISHER]

In this article, a compact tuneable F-slot monopole antenna for mobile handset applications, covering the DCS, PCS, and UMTS frequency bands, is presented and studied. An F-shaped slot is embedded in a rectangular monopole patch to accommodate the varactor. The tuning is accomplished by applying a lumped capacitor (varactor) across the slot arms of the patch. By varying the capacitance values of loaded capacitor from 0.5 to 3 pF, the antenna is capable of achieving high tuning ranges from 1.70 to 2.15 GHz. The antenna performance is characterized in terms of the reflection coefficient, radiation pattern, and power gain. The predicted and measured results show fairly good agreement and confirm satisfactory impedance bandwidth characteristics and consistent radiation patterns over the tuned frequency range. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:794-802, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26649 [ABSTRACT FROM AUTHOR]

A planar printed PIFA is proposed and fabricated in this work, which is promising for internal mobile applications. In the design, the presented antenna consists of a feeding strip and a coupling strip (which is short-circuited to the system ground by a long shorting strip). By the coupled-fed excitation, the proposed antenna can generate multiple resonant modes at lower and upper bands for seven-band WWAN operation, covering GSM850/900/DCS1800/PCS1900/UMTS2100/LTE2300/2500. In detail, the feeding strip can excite high frequency current distributions on the coupling strip by a coupling gap to generate a fundamental resonant mode at around 800 MHz, while the desired upper resonant modes at about 1850 MHz and 2550 MHz can be achieved by the feeding strip itself. The proposed antenna occupies a size of 15 × 45 mm2 and is easily printed on one surface of a FR4 substrate as system circuit board, which makes it suitable for practical mobile applications. Finally, the simulated and measured results are given, which obtain good agreement and illuminate the reliability of the scheme. [ABSTRACT FROM AUTHOR]

Background: Repeated data collection is desirable when monitoring fluctuating conditions. Mobile phones can be used to gather such data from large groups of respondents by sending and receiving frequently repeated short questions and answers as text messages. The analysis of repeated data involves some challenges. Vital issues to consider are the within-subject correlation, the between measurement occasion correlation and the presence of missing values. The overall aim of this commentary is to describe different methods of analyzing repeated data. It is meant to give an overview for the clinical researcher in order for complex outcome measures to be interpreted in a clinically meaningful way. Methods: A model data set was formed using data from two clinical studies, where patients with low back pain were followed with weekly text messages for 18 weeks. Different research questions and analytic approaches were illustrated and discussed, as well as the handling of missing data. In the applications the weekly outcome "number of days with pain" was analyzed in relation to the patients' "previous duration of pain" (categorized as more or less than 30 days in the previous year). Research questions with appropriate analytical methods 1: How many days with pain do patients experience? This question was answered with data summaries. 2: What is the proportion of participants "recovered" at a specific time point? This question was answered using logistic regression analysis. 3: What is the time to recovery? This question was answered using survival analysis, illustrated in Kaplan-Meier curves, Proportional Hazard regression analyses and spline regression analyses. 4: How is the repeatedly measured data associated with baseline (predictor) variables? This question was answered using generalized Estimating Equations, Poisson regression and Mixed linear models analyses. 5: Are there subgroups of patients with similar courses of pain within the studied population? A visual approach and hierarchical cluster analyses revealed different subgroups using subsets of the model data. Conclusions: We have illustrated several ways of analysing repeated measures with both traditional analytic approaches using standard statistical packages, as well as recently developed statistical methods that will utilize all the vital features inherent in the data. [ABSTRACT FROM AUTHOR]

Here a compact wideband diversity antenna covering the PCS/UMTS/WiMAX bands with high isolation and low enveloped correlation coefficient (ECC) is proposed. To widen the bandwidth, the proposed antenna uses a structure with a gap-coupled feed and an inductively shorted line that has capacitive compensation between the radiator and the ground plane. Also, a suspended line with a parasitic element is used to enhance the isolation between the two antennas. [ABSTRACT FROM AUTHOR]

Abstract: In smart environments, pervasive computing contributes in improving daily life activities for dependent people by providing personalized services. Nevertheless, those environments do not guarantee a satisfactory level for protecting the user privacy and ensuring the trust between communicating entities. In this paper, we propose a trust evaluation model based on user past and present behavior. This model is associated to a lightweight authentication key agreement protocol (EC-SAKA). The aim is to enable the communicating entities to establish a level of trust and then succeed in a mutual authentication using a scheme suitable for low-resource devices in smart environments. Finally, we tested and implemented our scheme on Android mobile phones in a smart environment dedicated for handicapped people. [Copyright &y& Elsevier]

A planar antenna for multiband operation is presented.The proposed microstrip-fed antenna includes a slotted ground plane, a T-shaped radiator, meandered and open circuit strips. A return loss of better than 10 dB is achieved at the frequency bands personal communication system (PCS) (1850-1990 MHz), UMTS (1920-2170 MHz), WiBro (2300-2390 MHz), WLAN + Bluetooth (2400-2480 MHz), WiMAX (2500-2690 MHz), and WiMAX (3400-3600 MHz). If a return loss of 6 dB is considered as a standard, the antenna can cover DCS (1710-1880 MHz). The proposed antenna occupies a small volume of 40 × 30 × 1.6 mm3, which makes it attractive to the portable devices. The simulated and measured performance of the antenna confirms its multiband operation and omnidirectional radiation pattern. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2700-2703, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26319 [ABSTRACT FROM AUTHOR]

A novel hexa-band antenna for mobile handsets application is proposed and analyzed in this communication. An asymmetric T-type monopole antenna with a shorted-line is designed to be operated in code-division multiple access (CDMA, 824–894 MHz), global system for mobile communications (GSM, 880–960 MHz), digital communication system (DCS, 1710–1880 MHz), personal communication system (PCS, 1850–1990 MHz), wideband code division multiple access (WCDMA, 1920–2170 MHz) and Bluetooth (2400–2484 MHz) bands. A prototype of the proposed antenna with 50 mm in length, 3 mm in height and 15 mm in width is fabricated and experimentally investigated. The experimental results indicate that the VSWR 2.5:1 bandwidths achieved were 17.8% and 37.1% at 900 MHz and 2100 MHz, respectively. The specific absorption rate (SAR) for an input power of 24 dBm in CDMA, GSM and WCDMA bands, and an input power of 21 dBm in DCS and PCS bands all meet the SAR limit of 1.6 mW/g. Experimental results are shown to verify the validity of theoretical work. [ABSTRACT FROM PUBLISHER]

In this article, the author describes how she use cell phones and suggests ways to engage students in using cell phones in adult education classes. The author considers the issues concerning the use of cell phones in adult education classrooms. She also describes the effective mobile phone techniques that she used during her adult education.

This article presents a compact multiband planar inverted-F antenna design for mobile phone applications. The proposed antenna comprises dual twisted lines, a shorting strip and an L-shaped coupling strip. The dual twisted lines are excited by the coupling strip to generate four resonance modes around 900, 1800, 2100, and 3500 MHz and covers six bands including the global system for mobile communication 850/900 (824-894 MHz), (880-960 MHz), digital communication system (1710-1880 MHz), personal communication system (1850-1990 MHz) universal mobile telecommunication system (1920-2170 MHz) and worldwide interoperability for microwave access (3400-3600 MHz). The antenna shows a planar structure and occupies a very small-size of 15 × 26 mm, making it especially suit for mobile phone applications. This research performed simulation by high frequency structure simulation and CST to design and analyze the antenna, and a practical structure was fabricated and tested. The measured and simulated return loss show good agreement. Moreover, the radiation patterns and the specific absorption rate are discussed too. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1233-1236, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25996 [ABSTRACT FROM AUTHOR]

A quad-band printed planar inverted-F antenna with two meander strips is proposed, designed, and tested. Its geometry is mainly comprised of an inverted meandered U-shaped shorting strip and a tunable T-shaped shorting strip for providing two operating bands at center frequency about 900 MHz and 1940 MHz to cover four bands: GSM, DCS, PCS, and UMTS with a small area of 15 × 33 mm. The antenna can be easily fed by a 50-Ω feed-line without any external matching circuit or lumped circuit elements for size reduction or bandwidth enhancement. It is easy to fabricate at low cost and especially fit for thin-profile mobile phone application. Good impedance and radiation performances are obtained. Details of the proposed antenna and the obtained results are also presented. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:68-72, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25629 [ABSTRACT FROM AUTHOR]

This paper reviews existing work on mobile telephones. It finds that extensive research work has been done on mobile telephone uses in Ghana. The papers found that no work has been done on the impact of mobile telephony on creating high-paying jobs that promote socio-economic development in Ghana. The study proposes implementation of mixed methodology research to examine the perspective of the five mobile service operators in Ghana and their contribution to the promoting of socio-economic development in. The papers also designs questionnaire that will be used to survey management staff-- senior executives, marketing, finance, accounting and operations research staff-- from the telephone services providers' respective headquarters in Ghana. [ABSTRACT FROM AUTHOR]

MOBILE operators are in a bind. The uptake of smartphones has led to an unprecedented increase in the volume of data flowing over their networks. They've been scrambling to keep up, investing in capacity even as they consolidate their 3G networks and make ready for a shift to 4G technologies. The Next Generation Mobile Networks (NGMN) Alliance, which exists to ease the transition from current to 4G networks, is already concerned about the operating costs of the new networks, and so is pushing equipment vendors to come up with systems that can manage themselves, as well as interoperability at the network and service-management level so that equipment from different vendors can collaborate to optimise overall performance. [ABSTRACT FROM AUTHOR]

In this letter, fully embedded passive triplexer and quintplexer module into organic packaging substrate were presented for US CDMA handset applications. First, the passive triplexer was implemented by embedding all passive elements and circuits into multilayered organic packaging substrate. The passive triplexer circuit with eight passive elements was comprised of a diplexer, parallel resonator, and matching network. The size of the fabricated triplexer was 3 mm × 4 mm. The compact CDMA quintplexer module was fabricated by assembling the embedded passive triplexer with DCN and PCS duplexers on FR-4 evaluation board. A fabricated quintplexer module exhibited an insertion loss of -2.2 dB/-2.9 dB at DCN Tx/Rx band, -3 dB/-2.7 dB at PCS Tx/Rx band, and -2.4 dB at GPS Rx band, respectively. In addition, the stop-band attenuation is -40 dB/-44 dB at DCN Tx/Rx band, -55 dB/-45 dB at PCS Tx/Rx band, and -37 dB at GPS Rx band, respectively. Measured isolations in each Tx band are -62 dB/-58 dB at GPS/PCS of DCN band, -30 dB/-36 dB at DCN/PCS of GPS band, and -45 dB/-38 dB at DCN/GPS of PCS band. It is comparatively much higher than the matching circuit type quintplexer module, which indicates that the embedded triplexer is strongly applicable for improving the interferer blocking. The simulated performance characteristics were agreed with the simulated ones. ©2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 302–306, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24923 [ABSTRACT FROM AUTHOR]

This paper presents an approach to the relationship between youth identities and cellular phone technology, in order to explain the transition from a social landscape in which traditional mass communication media used to predominate to the actual one, a new "personal communication society". The methodology was built up taking into account: theory discuss (from authors like Marc Augé, Georg Simmel, Manuel Castells, Martín-Barbero and other specialists on mobile telephony); concept articulation with national statistics data and some explorative (but not probabilistic) research by informally interviewing young people. Youths seem to find in mobile communication an ideal way of expression and reassurance on which many of the dimensions which characterize young urban cultures rely. [ABSTRACT FROM AUTHOR]

Abstract: This study examined teens’ use of socially interactive technologies (SITs), such as online social sites, cell phones/text messaging, and instant messaging (IM), and the role that social anxiety plays on how teens communicate with others (technologically or face-to-face). Participants included 280 high school students from a large western city. On average, 35–40% of teens reported using cell phones/text messaging and online social sites between 1 and 4h daily, 24% reported using IMs 1–4h daily and only 8% reported using email between 1 and 4h daily. Females tended to use cell phones/text messaging and online social sites more so than did males. In assessing social anxiety, analyses revealed a positive relationship between social anxiety (not comfortable talking with others face-to-face) and (1) talking with others online and (2) talking with others via text messaging. In contrast, there was a positive relationship between the lack of social anxiety (feeling “comfortable” talking with others) and making friends online. Assessing gender differences and social anxiety also revealed significant differences. Results revealed females reported more social anxiety (not comfortable talking with others in person) than did males. In addition, females, more than males, reported feeling more comfortable using SITs (text messaging and online social sites only) rather than talking with others face-to-face. [Copyright &y& Elsevier]

Mobility database that stores the users’ location records is very important to connect calls to mobile users on personal communication networks. If the mobility database fails, calls to mobile users may not be set up in time. This paper studies failure restoration of mobility database. We study per-user location record checkpointing schemes that checkpoint a user’s record into a non-volatile storage from time to time on a per-user basis. When the mobility database fails, the user location records can be restored from the backup storage. Numeric analysis has been used to choose the optimum checkpointing interval so that the overall cost is minimized. The cost function that we consider includes the cost of checkpointing a user’s location record and the cost of paging a user due to an invalid location record. Our results indicate that when user registration intervals are exponentially distributed, the user record should never be checkpointed if checkpointing costs more than paging. Otherwise, if paging costs more, the user record should be always checkpointed when a user registers. [ABSTRACT FROM AUTHOR]

To better understand the dynamics of cell phone use among a sample of college students and their attachment for their parents, our study investigated the attitudes toward cell phone use, distinguishing patterns of cell phone users, and user group and gender differences related to attachment to parents among college students. Findings of this study point to implications for further research in three areas: cell phone use and adoption of special functions, family studies, and measurement improvement. [ABSTRACT FROM AUTHOR]

Research shows that text messages, short type-written messages sent via mobile telephones, are primarily being used to commence, advance, maintain, or otherwise impact interpersonal relationships. This study describes how respondents perceive and use text messages within close interpersonal dyads. Interviews with dyads resulted in three main themes. Users found texting to be more constant and private than mobile voice interaction. Respondents used texting both to assert autonomy and to maintain connectedness with relational partners. Romantic pairs vis-a-vis nonromantic dyads perceived the benefits of text messages differently. [ABSTRACT FROM AUTHOR]

The RELATE interaction model is designed to support spontaneous interaction of mobile users with devices and services in their environment. The model is based on spatial references that capture the spatial relationship of a user’s device with other co-located devices. Spatial references are obtained by relative position sensing and integrated in the mobile user interface to spatially visualize the arrangement of discovered devices, and to provide direct access for interaction across devices. In this paper we discuss two prototype systems demonstrating the utility of the model in collaborative and mobile settings, and present a study on usability of spatial list and map representations for device selection. [ABSTRACT FROM AUTHOR]

Whilst there is a wealth of research into family communication and family relationships, there is little information about whether (and if so how) mobile phones have impacted on these processes. The authors’ study involved individual semi-structured interviews with 60 families, including parents/carers and young people aged 11–17, to investigate this further. The interviews explored how mobile phones are used in family communication; participants’ views about the benefits and disadvantages of mobile phone use; and issues around safety, surveillance and privacy. The findings show that young people and parents see mobiles as a key way for families to keep in touch, and to monitor and ensure young people’s safety. However, some participants felt there was a downside to this, in relation to some young people either withdrawing into their own social worlds, or having a false feeling of security as a result of having a mobile. Gender differences in views and usage were also found. The paper concludes with some general comments about the role of mobile phones in family life. [ABSTRACT FROM AUTHOR]

Many real-world systems (such as cellular telephones, transportation, etc.) are Multi-state Node Networks (MNNs) that are composed of multi-state nodes with different states determined by a set of nodes receiving the signal directly from these nodes without satisfying the conservation law. Current methods for evaluating MNN reliability are all derived from Universal Generating Function Methods (UGFMs). Unfortunately, UGFMs are only effective for special MNNs without any cycle, i.e. acyclic MNNs. A very simple revised UGFM is developed for the general MNN reliability problem. The proposed UGFM allows cycles with the same time complexity as the best-known UGFM. The correctness and computational complexity of the proposed UGFM are analyzed and proven. One example is given to illustrate how MNN reliability is evaluated using the proposed UGFM. [ABSTRACT FROM AUTHOR]

Cellular networks are a critical component of the economic and social infrastructures in which we live. In addition to voice services, these networks deliver alphanumeric text messages to the vast majority of wireless subscribers. To encourage the expansion of this new service, telecommunications companies offer connections between their networks and the Internet. The ramifications of such connections, however, have not been fully recognized. In this paper, we evaluate the security impact of the SMS interface on the availability of the cellular phone network. Specifically, we describe the ability to deny voice service to cities the size of Washington DC and Manhattan with little more than a cable modem. Moreover, attacks targeting the entire United States are feasible with resources available to medium-sized zombie networks. This analysis begins with an exploration of the structure of cellular networks. We then characterize network behavior and explore a number of reconnaissance techniques aimed at effectively targeting attacks on these systems. We conclude by discussing countermeasures that mitigate or eliminate the threats introduced by these attacks. [ABSTRACT FROM AUTHOR]

Abstract: Mobile phones, which were introduced around a decade ago in 1995–1996 in India, are becoming the dominant means of accessing communication. At the end of 2005–2006, there were 90 million mobile subscribers in India in comparison to 50 million subscribers for landlines. The increase in mobile phones has been phenomenal in comparison with landlines since the introduction of mobiles in the country. The main aim of this paper is to estimate future trends and analyze the pattern and rate of adoption of mobile phones in India. The paper uses S-shaped growth curve models for the same. It is found that mobile-density (number of mobile phones per 100 inhabitants) in India will increase from 8.1 in 2005–2006 to 36.5 in 2010–2011 and 71 in 2015–2016. Consequently, the mobile subscriber base is projected to increase from 90 million in 2005–2006 to 433 million in 2010–2011 and nearly 900 million in 2015–2016. The projected rapid growth in the mobile subscriber base will have important implications for future plans of mobile operators, infrastructure providers, handset suppliers and vendors. Mobile operators should be ready with contingency plans to deploy and operate infrastructure including customer care, billing, applications, etc., faster than that they might have initially planned. Infrastructure providers, handset suppliers and vendors should be prepared to respond to such plans. [Copyright &y& Elsevier]