Network computing

We consider a scenario where a sophisticated jammer jams an area in a single-channel wireless sensor network. The jammer controls the probability of jamming and transmission range to cause maximal damage to the network in terms of corrupted communication links. The jammer action ceases when it is detected by a monitoring node in the network, and a notification message is transferred out of the jamming region. The jammer is detected at a monitor node by employing an optimal detection test based on the percentage of incurred collisions. On the other hand, the network computes channel access probability in an effort to minimize the jamming detection plus notification time. In order for the jammer to optimize its benefit, it needs to know the network channel access probability and number of neighbors of the monitor node. Accordingly, the network needs to know the jamming probability of the jammer. We study the idealized case of perfect knowledge by both the jammer and the network about the strategy of one another, and the case where the jammer or the network lack this knowledge. The latter is captured by formulating and solving optimization problems, the solutions of which constitute best responses of the attacker or the network to the worst-case strategy of each other. We also take into account potential energy constraints of the jammer and the network. We extend the problem to the case of multiple observers and adaptable jamming transmission range and propose a intuitive heuristic jamming strategy for that case.

Satellite-based information on significant waves is increasingly being made available to ocean scientists and engineers at low costs. While such measurements have a number of useful applications the manner with which the satellites sense the waves limits their applications to nearshore locations. This paper discusses an approach based on the radial basis function (RBF) type of artificial neural networks to map remote-sensed deep-water waves with the coastal waves. Significant wave heights at a number of locations over a track parallel to the coastline are used to estimate the significant wave heights at a nearshore site. The success of the method adopted was confirmed from the satisfactory error measures it produced during the testing carried out following the network training. It was also found that the satellite data need a 'local tuning' as done in the RBF before their further use in network computations. This work also highlighted importance of innovative approaches to calibrate a network on the basis of a given data set.

Geant4 is a very large, highly accurate toolkit for Monte Carlo simulation of particle-matter interaction. It has been applied to high-energy physics, cosmic ray modeling, radiation shields, radiation therapy, mine detection, and other areas. Geant4 is being used to help design some high energy physics experiments (notably CMS and Atlas) to be run on the future large hadron collider: the largest particle collider in the world. The parallelization, ParGeant4, represents a challenge due to the unique characteristics of Geant4: (i) complex object-oriented design; (ii) intrinsic use of templates and abstract classes to be instantiated later by the end user; (iii) large program with many developers; and (iv) frequent releases. The key issue for parallelization is not just how to parallelize "correctly" but also how to parallelize "with minimum effort". In addition, the parallelization should make as few assumptions about the source code as possible, due to the frequent release schedule of Geant4. We use TOP-C (Task Oriented Parallel C/C++) for parallelization and Marshalgen for marshaling/serialization. In some examples on a cluster of 100 nodes yielded a speedup of up to 94.4. The code's portability, scalability and performance are also discussed.

Abstract: Nowadays, user authentication is one of the important topics in information security. Text based strong password schemes could provide with certain degree of security. However, the fact that strong passwords being difficult to memorize often leads their owners to write them down on papers or even save them in a computer file. Graphical user authentication (GUA) has been proposed as a possible alternative solution to text based authentication, motivated particularly by the fact that humans can remember images better ...

Knowledge of the up-to-date network topology (i.e. Layer 2 & Layer 3) is crucial for efficient network management. Issues like congestion avoidance, resource management, resource discovery, root-cause analysis and event correlation require accurate information of the topology map. Due to dynamic nature of today's IP networks, keeping track of topology information manually is a daunting task. Thus efficient algorithms for automatically discovering physical network topology are necessary. The earlier work has typically concentrated on discovering topology either using completely SNMP-MIB or ICMP echo request/reply, DNS, Trace route, etc. Our proposed algorithm does not rely totally on SNMP-MIB information as it is not usually supported by all devices in the network. Instead we propose an approach where SNMP agent should only be enabled on the routers and managed switches. Rest of the network computers/hosts need not have SNMP agent enabled. We propose an efficient algorithm not only to find available computers/hosts but also to find appropriate timeouts and delays in the network. The experimental results validate our approach, demonstrating that our algorithm discovers accurate physical topology.

This article offers expert opinion on two Internet of Things (IoT) perspectives. The first is a research agenda for the IoT to ensure the development of a trusted, secure, reliable, and interoperable net-centric computing environment. The second discusses the IoT as a human agent, extension, and complement. Both discussions include accompanying video, available at http://youtu.be/ywjekHO1pAM and http://youtu.be/skX7DjB2lyg, respectively.

Children are considered particularly important in debates about the possibilities and dangers of information and communication technologies (ICT). Discourses on ICT contain paradoxical representations of childhood. On the one hand, unlike most other understandings of child/adult relations, these discourses assume children to be equally, if not more, technologically competent than adults. On the other hand, children's very competence at using ICT is alleged to be putting them "at risk" of abuse or corruption. This paper addresses these moral panics about children and ICT by exploring to what extent and why parents are concerned about their children's safety in on-line space. In doing so the paper reflects on the extent to which anxieties about children in cyberspace replicate concerns about public outdoor space and the way networked computers emerge as different tools in different households.

Purpose – This paper sets out the arguments for the use of social media as a tool for learning in the workplace. Design/methodology/approach – Not applicable – viewpoint paper Findings – Social media can play a valuable role in both formal and informal learning in those organizations in which employees have some discretion over how they use their time and

Peer-to-peer systems (P2P) have become a popular technique to architect decentralized systems. However, despite its popularity most P2P systems consist in simple applications such as file sharing or chat systems. The main reason is that more complex applications require levels of consistency that nowadays are not offered by P2P systems. In this paper, we explore how to provide consistency based on distributed mutual exclusion via quorum systems in DHTbased P2P networks. Our results show that quorum systems applied directly to such networks are not scalable due to the high traffic imposed onto the underlying network. The paper introduces some design principles for both quorum systems and protocols using them that help to boost their performance. These design principles consist in dynamic and decentralized selection of quorums and in the exposition and exploitation of internals of the DHT such as the finger table. We show that by combining both design principles it is possible to minimize the number of visited sites and the latency needed to obtain a quorum.

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As wireless sensor networks continue to grow, so does the need for effective security mechanisms. Because sensor networks may interact with sensitive data and/or operate in hostile unattended environments, it is imper- ative that these security concerns be addressed from the beginning of the system design. However, due to inherent resource and computing constraints, security in sen- sor networks poses

We developed Smart Furniture, which extemporaneously converts the legacy non-smart space into a Smart Hot-spot which consists of computational services. Since the Smart Furniture is equipped with networked computers, sensors and various I/O devices, it can provide various services by alone or by coordinating with other devices. In this paper, the physical structure and middlewares for the Smart Furniture are described. The prototype systems to

This study examined the pattern of use of different forms of contact between grandparents and grandchildren, and especially the use of new technologies (SMS, e-mail) and factors affecting this. Questionnaire data are reported from 408 grandparents in the UK, Spain, Finland and Estonia, regarding contacts with grandchildren mostly in the 10-15-year age range. Face-to-face contact remained the most frequent mean, followed closely by landline telephone; there was moderate use of mobile phones, and many used letters/cards occasionally; and a minority used SMS and e-mails (about one-half to one-third of those with mobile phones, and networked computers, respectively). When contacting grandchildren, most grandparents accumulate different forms of contact, but others compensate some forms of contact. There were no differences by age of grandparent, but grandmothers made more use of e-mail than grandfathers, as did more highly educated grandparents and those with older grandchildren. Implications for use of Information and Communication Technology by older people are discussed.

Some authors proposed that exact mental calculation is based on linguistic representations and relies on the perisylvian language cortices, while the understanding of proximity relations between numerical quantities implicates the parietal cortex. However, other authors opposed developmental arguments to suggest that number sense emerges from nonspecific visuospatial processing areas in the parietal cortex. Within this debate, the present study aimed at revealing the functional anatomy of the two basic resolution strategies involved in mental calculation, namely arithmetical fact retrieval and actual computation, questioning in particular the respective role of language and/or visuospatial cerebral areas. Regional cerebral blood flow was measured with positron emission tomography while subjects were at rest (Rest), read digits (Read), retrieved simple arithmetic facts from memory (i.e., 2 ؋ 4, Retrieve), and performed mental complex calculation (i.e., 32 ؋ 24, Compute). Compared to Read, Retrieve engaged a left parietopremotor circuit representing a developmental trace of a finger-counting representation that mediates, by extension, the numerical knowledge in adult. Beside this basic network, Retrieve involved a naming network, including the left anterior insula and the right cerebellar cortex, while it did not engage the perisylvian language areas, which were deactivated as compared to Rest. In addition to this retrieval network, Compute specifically involved two functional networks: a left parieto-frontal network in charge of the holding of the multidigit numbers in visuospatial working memory and a bilateral inferior temporal gyri related to the visual mental imagery resolution strategy. Overall, these results provide strong evidence of the involvement of visuospatial representations in different levels of mental calculation.

Background: Progressive remodelling of the left ventricle (LV) following myocardial infarction (MI) is an outcome of spatial-temporal cellular interactions among different cell types that leads to heart failure for a significant number of patients. Cellular populations demonstrate temporal profiles of flux post-MI. However, little is known about the relationship between cell populations and the interaction strength among cells post-MI. The objective of this study was to establish a conceptual cellular interaction model based on a recently established graph network to describe the interaction between two types of cells. Results: We performed stability analysis to investigate the effects of the interaction strengths, the initial status, and the number of links between cells on the cellular population in the dynamic network. Our analysis generated a set of conditions on interaction strength, structure of the network, and initial status of the network to predict the evolutionary profiles of the network. Computer simulations of our conceptual model verified our analysis. Conclusions: Our study introduces a dynamic network to model cellular interactions between two different cell types which can be used to model the cellular population changes post-MI. The results on stability analysis can be used as a tool to predict the responses of particular cell populations.

This paper discusses how a group leader computer tutor may aid students in learning collaborative skills in a co-operative learning environment. However, students need to learn collaborative skills and practice using them. The group leader computer tutor discussed in this paper is designed on the principles of co-operative learning, intelligent tutoring systems and computer-supported collaborative work within an intelligent collaborative learning system (ICLS). The group leader aims to facilitate group work on the task level and to teach students how to use collaborative skills in the discussion level as students work on networked computers in the Jigsaw method of co-operative learning. The ICLS and its group leader were used by two classes at a liberal arts university. Qualitative research shows that the students' co-operative attitudes changed and academic achievement improved from pre-to post-treatment. Students, especially, used the communication skill of openness in comment type discussions. The students enjoyed working collaboratively through the ICLS and their teachers thought that the experience was valuable for them.

This article proposes an adaptive connectionist model that implements an attributional account of cognitive dissonance. The model represents an attitude as the connection between the attitude object and behavioral-affective outcomes. Dis-204

The principles of robotics and control are widely taught in engineering subjects, however a common problem concerns the limited availability of expensive equipment with which students can work with, in order to acquire valuable practical 'hands on' experience. The MuMaTE virtual robotics and control project on the World Wide Web (www) was launched to evaluate the suitability of virtual learning environments, the Internet, and multimedia technologies within an engineering-based flexible learning program. Students using networked computers can access this facility to study a wide variety of on-line course material and perform a series of interactive experiments with real world laboratory hardware. This paper presents an on-line experiment, which enabled users to successfully control and observe the response of a commercial position servo system. The development of the project web server, interface electronics and control software is also discussed. MuMaTE: http://mumate. lboro.ac.uk Ó

▪   We explore the extent to which neocortical circuits generalize, i.e., to what extent can neocortical neurons and the circuits they form be considered as canonical? We find that, as has long been suspected by cortical neuroanatomists, the same basic laminar and tangential organization of the excitatory neurons of the neocortex is evident wherever it has been sought. Similarly, the inhibitory neurons show characteristic morphology and patterns of connections throughout the neocortex. We offer a simple model of cortical processing that is consistent with the major features of cortical circuits: The superficial layer neurons within local patches of cortex, and within areas, cooperate to explore all possible interpretations of different cortical input and cooperatively select an interpretation consistent with their various cortical and subcortical inputs.

Some authors proposed that exact mental calculation is based on linguistic representations and relies on the perisylvian language cortices, while the understanding of proximity relations between numerical quantities implicates the parietal cortex. However, other authors opposed developmental arguments to suggest that number sense emerges from nonspecific visuospatial processing areas in the parietal cortex. Within this debate, the present study aimed at revealing the functional anatomy of the two basic resolution strategies involved in mental calculation, namely arithmetical fact retrieval and actual computation, questioning in particular the respective role of language and/or visuospatial cerebral areas. Regional cerebral blood flow was measured with positron emission tomography while subjects were at rest (Rest), read digits (Read), retrieved simple arithmetic facts from memory (i.e., 2 ؋ 4, Retrieve), and performed mental complex calculation (i.e., 32 ؋ 24, Compute). Compared to Read, Retrieve engaged a left parietopremotor circuit representing a developmental trace of a finger-counting representation that mediates, by extension, the numerical knowledge in adult. Beside this basic network, Retrieve involved a naming network, including the left anterior insula and the right cerebellar cortex, while it did not engage the perisylvian language areas, which were deactivated as compared to Rest. In addition to this retrieval network, Compute specifically involved two functional networks: a left parieto-frontal network in charge of the holding of the multidigit numbers in visuospatial working memory and a bilateral inferior temporal gyri related to the visual mental imagery resolution strategy. Overall, these results provide strong evidence of the involvement of visuospatial representations in different levels of mental calculation.

Inexpensive fixed wing UAVs are increasingly useful in remote sensing operations. They are a cheaper alternative to manned vehicles, and are ideally suited for dangerous or monotonous missions that would be inadvisable for a human pilot. Groups of UAVs are of special interest for their abilities to coordinate simultaneous coverage of large areas, or cooperate to achieve goals such as mapping. Cooperation and coordination in UAV groups also allows increasingly large numbers of aircraft to be operated by a single user. Specific applications under consideration for groups of cooperating UAVs are border patrol, search and rescue, surveillance, communications relaying, and mapping of hostile territory. The capabilities of small UAVs continue to grow with advances in wireless communications and computing power.

Even as mobile computing and network computing are gaining momentum, Internet security is sharing the spotlight. Security and authentication on open networks is already a difficult problem, even without the additional risks posed by wireless media and the additional software constraints imposed by mobile computing devices with capabilities more modest than those of full-blown laptops. We describe an implemented indirect protocol called Charon, which provides authentication and secure communication to clients by leveraging the strong protocol and deployed infrastructure of Kerberos IV. Charon consists of a portable proxy module that runs as untrusted, unprivileged code, and an extremely lightweight client module that runs quite efficiently even on our Sony MagicLink PDA. This partitioning of functionality makes Charon attractive for ISP's and network computing as well as existing mobile devices. Charon's security is at least as strong as that of Kerberos--the user's password never leaves the mobile device, and Charon cannot obtain Kerberos services for the user without the user's explicit cooperation on each request. In effect Charon allows the mobile device to function as a smart card. We describe our implementation of the protocol and a sample secure rlogin application, and also describe how Charon can be used to implement cross-roaming agreements between mobile computing domains.

S ophisticated consumer devices that support multimedia-personal digital assistants, network computers, and mobile communication devices-pose challenges for embedded-systems designers. The low-cost, consumer-oriented, fast time-to-market mentality that dominates embedded-system design today forces design teams to use hardwaresoftware codesign to cope with growing design complexities. New codesign methodologies and tools must support a key characteristic of next-generation embedded systems: the capability to communicate over networks and adapt to different operating environments.

This paper presents a project devoted to developing an open system architecture for functionally based (implicit or more generally F-rep) shape modeling and its applications. The software tools are built around the shape models written in a highlevel programming language called HyperFun. A model in HyperFun can serve as a protocol for exchanging F-rep models between users, modeling systems, or networked computers. HyperFun models can be collected in application-specific libraries. We describe the basic set of system components: an interpreter for parsing and function evaluation; F-rep system libraries; a modeler with an extendable graphical user interface; a multidimensional modeler with a symbolic user interface providing means for interpreting multidimensional coordinates and constructing scenes; applications for visualization (polygonization, VRML generation, ray-tracing), animation, voxelization and others; a collaborative Internet-based modeler including a HyperFun-to-Java translator and advanced interactive techniques based on the "empirical modeling" paradigm. These components are intended to be public domain to stimulate collaborative development efforts.

Absrract --The switched-capacitor transconductance is used to simulate a new FDNR element which is relatively insensitive to parasitic capacitances and requires few components. The element is used in the switched-capacitor simulation of a fifth-order LC low-pass filter. It is shown that the influence of other switched parasitic capacitances, occurring in the filter due to the switches, can be eliminated by predistortion and that the resulting network is, except for a flat loss, equivalent to the original ideal network. Computational and experimental results, obtained on a network with discrete components, are presented.

We present a taxonomy of the agents involved in network computing, introduce models capable to describe different levels of reliability and Quality of Service required by a service contract and discuss architectural requirements for each model.

Network security issues and game exploits can undermine the gameplay experience of networked games. With this in mind, this work tries to draw attention of the academic community to the issue and, through a vast bibliography, present: why research in this area matters, the state of current research in the field, a categorization of cheating types and, also, some possible

Networks of neurons in the cerebral cortex generate complex outputs that are not simply predicted by their inputs. These emergent responses underlie the function of the cortex. Understanding how cortical networks carry out such transformations requires a description of the responses of individual neurons and of their networks at multiple levels of analysis. We focus on orientation selectivity in primary visual cortex as a model system to understand cortical network computations. Recent experiments in our laboratory and others provide significant insight into how cortical networks generate and maintain orientation selectivity. We first review evidence for the diversity of orientation tuning characteristics in visual cortex. We then describe experiments that combine optical imaging of orientation maps with intracellular and extracellular recordings from individual neurons at known locations in the orientation map. The data indicate that excitatory and inhibitory synaptic inputs are summed across the cortex in a manner that is consistent with simple rules of integration of local inputs. These rules arise from known anatomical projection patterns in visual cortex. We propose that the generation and plasticity of orientation tuning is strongly influenced by local cortical networks-the diversity of these properties arises in part from the diversity of neighbourhood features that derive from the orientation map.

We propose a method to compute a probably approximately correct (PAC) normalized histogram of observations with a refresh rate of Âð1Þ time units per histogram sample on a random geometric graph with noise-free links. The delay in computation is Âð ffiffiffi n p Þ time units. We further extend our approach to a network with noisy links. While the refresh rate remains Âð1Þ time units per sample, the delay increases to Âð ffiffiffi n p log nÞ. The number of transmissions in both cases is ÂðnÞ per histogram sample. The achieved Âð1Þ refresh rate for PAC histogram computation is a significant improvement over the refresh rate of Âð1= log nÞ for histogram computation in noiseless networks. We achieve this by operating in the supercritical thermodynamic regime where large pathways for communication build up, but the network may have more than one component. The largest component however will have an arbitrarily large fraction of nodes in order to enable approximate computation of the histogram to the desired level of accuracy. Operation in the supercritical thermodynamic regime also reduces energy consumption. A key step in the proof of our achievability result is the construction of a connected component having bounded degree and any desired fraction of nodes. This construction may also prove useful in other communication settings on the random geometric graph.

A family of message propagation protocols for highly mobile ad-hoc networks is defined, and is studied analytically and by simulation. The coverage of a message (the fraction of nodes that receive it), can be made arbitrarily close to 1, at a moderate cost of extra message traffic. Under certain simplifying assumptions, it is shown that a high coverage is achieved by making a total of O(n ln n) broadcasts, where n is the number of nodes, and the time to propagate a message is O(ln n). Mechanisms for making the protocols more efficient, by reducing the number of redundant transmissions without affecting the achievable coverage, are presented and evaluated. The generalisation to multiple broadcasts proceeding in parallel is derived. Finally, an attempt to validate the proposals in the context of a real-life mobile ad-hoc network is described. Results of this validation exercise and simulations point out that the proposed protocols can cost-effectively achieve high coverage in networks of varying degrees of node densities and mobilities.

The Jackson Laboratory Colony Management System (JCMS) is a software application for managing data and information related to research mouse colonies, associated biospecimens, and experimental protocols. JCMS runs directly on computers that run one of the PC Windows® operating systems, but can be accessed via web browser interfaces from any computer running a Windows, Macintosh®, or Linux® operating system. JCMS

A common problem faced by institutions concerns the limited availability of expensive robotics and control equipment, with which students in the educational program can work, in order to acquire valuable 'hands on' experience. The Multiple Manipulators for Training and Education (MuMaTe) virtual control and robotics laboratory was launched on the World Wide Web (WWW). Its aim was to evaluate the

The paper would discuss the possibilities of using cloud computing as a solution to expand work efficiency at Taiz
university (TU) Computer Center and Information Technology (CCIT) labs, these Labs equipped with hardware and
software resources. Cloud computing has been adopted for managing the labs to facilitate maintenance and network
management according to cloud computing characteristics, also paper has studied the different types of cloud-based
computing to decide the appropriate type that would gain significant advantages for students and lecturers. Surely
result of this paper will be the guideline for all universities in Yemen to use the cloud computing in different areas of
their work

The proliferation of information sources as a result of networked computers and other interconnected devices has prompted significant changes in the amount, availability, and nature of geographic information. Among the more significant changes is the increasing amount of readily available volunteered geographic information. Although volunteered information has fundamentally enhanced geographic data, it has also prompted concerns with regard to its quality, reliability, and overall value. This essay situates these concerns as issues of information and source credibility by (a) examining the information environment fostering collective information contribution, (b) exploring the environment of information abundance, examining credibility and related notions within this environment, and leveraging extant research findings to understand user-generated geographic information, (c) articulating strategies to discern the credibility of volunteered geographic information (VGI), including relevant tools useful in this endeavor, and (d) outlining specific research questions germane to VGI and credibility.

The routing scalability and IP address exhaustion are two significant issues the current Internet faces. The "locator/identifier (Loc/ID) split" has become a well recognized design principle for future Internet architectures that make Internet routing more scalable. In this paper, a novel Loc/ID split routing and addressing architecture called IPv4+6 is proposed. It not only solves the routing scalability problem but also expands the IP address space. It is easy to deploy, which only needs to make simple changes on DNS and gateway router.

This paper describes a novel approach to implement multimedia access platforms: reconfigurable oriented codesign. Nowadays we observe a rapid and mutant evolution of multimedia standards and its de facto adoption into many consumer electronics, such as audio/video appliances, digital set-top boxes for TV access networks, mobile technologies and portable digital assistants (PDAs). Among the disadvantages of current multimedia access platforms, we can mention the relative high cost, the very short obsolescence cycles, the communication and computational performance limitations, the large sizes of software components, and system architectures that do not match future multimedia standards requirements. To overcome these, we propose the use of a reconfigurable computing architecture to implement a family of multimedia access platforms. As an example, we present an implementation of a multimedia access platform that runs a web browser (HTML 3.2 compatible) over a 32-bit RISC microprocessor, described using less than 256 Kbytes of data to represent software and hardware components on a FPGA (Field Programmable Gate Array).

An adaptive distributed strategy is developed based on incremental techniques. The proposed scheme addresses the problem of linear estimation in a cooperative fashion, in which nodes equipped with local computing abilities derive local estimates and share them with their predefined neighbors. The resulting algorithm is distributed, cooperative, and able to respond in real time to changes in the environment. Each node is allowed to communicate with its immediate neighbor in order to exploit the spatial dimension while limiting the communications burden at the same time. A spatial-temporal energy conservation argument is used to evaluate the steady-state performance of the individual nodes across the entire network. Computer simulations illustrate the results.

In systems where customer service demands are only known probabilistically, there is very little to distinguish between jobs. Therefore, no universal optimum scheduling strategy or algorithm exists. If the distribution of job times is known, then the residual time (expected time remaining for a job), based on the service it has already received, can be calculated. In a detailed discrete event simulation, we have explored the use of this function for increasing the probability that a job will meet its deadline. We have tested many different distributions with a wide range of and shape, four of which are reported here. We compare with RR and FCFS, and find that in all distributions studied our algorithm performs best. We also studied the use of two slow servers versus one fast server, and have found that they provide comparable performance, and in a few cases the double server system does better. 2 σ

The Network Time Protocol, an over 2-decade old and always improving algorithm for synchronizing networked computer clocks, still finds problems for its efficient operation. Many applications need a trustable time system to function correctly (e.g., banking and distributed database servers). With the advent of Quality of Service in computer networks, this problem can be elegantly approached and solved. This article suggests a framework for dealing with clock synchronization on DiffServ Domains, introduces a novel treatment to packets and validates this proposal on a case-study done with live application metrics in a network emulation environment.

Computer mediated communication (CMC) refers to communication between individuals and among groups via networked computers. Such forms of communication can be asynchronous or synchronous and serve a wide variety of useful functions ranging from administration to building understanding and knowledge. As such there are many reasons for interest in analyzing the content of CMC. Foremost among these is the opportunity that the written text is able to offer for various types of analysis. Others have to do with the need to understand human communication patterns in this medium, their conventions, form and functions, the nature of the subtext within it, and how people derive meaning and understanding in such contexts. The papers in this special section of this journal have attempted to closely examine the subject of CMC content analysis. It includes examination of what is involved in the analysis of CMC content, schemes and frameworks for analyzing them, and knowledge building within such contexts.