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This article discusses the emerging innovations in wireless network technologies and how they will continue to represent a rapidly growing sector. Third generation (3G) mobile networks offer broadband transmission with speeds of up to 2 megabytes per second (Mbps) in some areas of the world. The international 3G networks standard, IMT-2000, defines no less than five incompatible 3G wireless standards, three of which are in different stages of realization, complicating the problem of interoperability of wireless networks.

This article discusses digital networks, networked businesses, and how companies that combine different capabilities are more agile and move positions faster. Using the example of the book retailer Amazon, the author demonstrates how without stores and with limited inventory, Amazon has more information on retail goods and their buyers and sellers than many other businesses. Within Amazon's business networks, retailers can facilitate a search by buyers and sellers, manage and coordinate the logistical processes for transfer of the physical or digital goods, settle payments, and authenticate the quality of the goods sold.

The article discusses methods to measure the effectiveness of corporate intranet networks. While many corporations place a great deal of importance and invest a lot of time and money in their intranets, most do not have a reliable means of seeing how the intranets meet specific business needs, if they do at all. The authors state that companies need to move beyond usage statistics as a way of measuring effectiveness and develop tools to reveal the tangible impacts of intranets on business productivity.

The article presents information about an extensive study on the community-oriented wireless commons. In the wireless arena, several community-oriented wireless commons are emerging in parallel to provide wireless access to community members and create alternate wireless broadband networks. Wireless commons are based on the notion that each commons participants allow other participants to access the Internet through his or her wireless local area networks (WLANs) hotspot. In a wireless commons, therefore, the user is both a provider and a consumer of wireless. This emergent, organic growth approach depends on the commitment and contributions of participants willing to share their WLANs with others. Closed commons are made up of a specified group of user members. These groups are characterized by shared understanding, common history, written rules, and accepted norms for resource utilization and sanctions for violators. Open commons are formed by communities and enthusiasts with the objective of providing bandwidth resources free of charge to the general public.

"In an example, at least one electronic table mat is configured to communicate with the user terminal via a communication hub device that comprises a wireless communication device for communicating with a wireless communication network. The ordering system of claim 1, and a communication hub device comprising a wireless communication device for communicating with a wireless communication network, wherein at least one said electronic table mat is configured to communicate with said user terminal via said communication hub device. "In an example. at least a first of the plurality of electronic table mats and a second of the plurality of second electronic table mats are configured to communicate by means of a wireless connection between them. [Extracted from the article]

The article presents information on the development of quantum computers. This super-powerful technology is already being lined up for military and government code-breaking applications. It might appear in the form of a highly destructive hidden logic gate that flips or erases quantum bits. Maybe it will be a quantum algorithm designed to scramble data in particularly malicious ways. The idealized quantum computer is a network of isolated particles. The quantum states of particles are used to represent the 1s and 0s that are the bread and butter of digital computing.

Mesh networking is a technique for creating self-organizing clusters of computers that make their own connections between one another, spreading their coverage one node at a time across any terrain, with no central planning authority. It could be described as organized anarchy. The Wi-Fi standard for wireless local area networking, which allows any computer fitted with a cheap Wi-Fi card to link to a network, without being tied to fixed wires or even a fixed location. Combine the mesh networking and Wi-Fi and the result is a network with virtually no size limit, which can grow organically as and when required. INSET: THE WILD WIRELESS FRONTIER.

E-speak started with a very modest goal-- simply to change the way the world thinks about computing. Today, we think about computing as the hardware we buy and the software we install on it. E-speak is all about thinking of computing as a set of services we enlist as we need them. E-speak is a layer of software running on collections of equipment that provides a set of mechanisms for solving this common set of problems. Because the mechanisms are the same for everyone, it's easier for the two parties to interoperate. E-speak also provides a language for specifying a variety of policies. It is this combination of a platform providing the common set of mechanisms and the language for setting policy that makes e-speak a critical part of the open services marketplace. E-speak addresses the key problems of the open services marketplace--naming, discovery, management security, programming, and interoperability-in a single, coherent architecture. INSET: E-SPEAK'S HISTORY..

Only a few years ago, most networks were LANs with limited linkages between equipment. During that era, networks were managed via the centralized architecture. Since this architecture is simple and effective, network administration tasks were carried out on a personal computer or workstation. But the recent growth of Internet applications has led to an explosion in the number of networks worldwide, which has placed a heavy burden upon the networks as well as the administrators. It is not surprising then, that the conventional centralized architecture is not sufficient to manage such changes. In this architecture, the central network server routinely requests the status information of local units, which consumes a significant amount of bandwidth. In addition, communication data may be lost during transmission. It is therefore common today to share management tasks with other network management servers in a distributed framework. INSET: The Network Management System..

This article reports on the service creation and management in active telecommunication management. A recent research in the area of active networking has demonstrated strong potential for this new technology. From the service point of view active networking allows customized packet processing inside the network on a per-packet, per-flow, or per-service basis. From the management perspective, active networking technology facilitates rapid service deployment and flexible service management. The paradigm of active networking allows a party to install and run a service on a network in a manner similar to the way a program is installed and executed on a computer. While suggesting attractive benefits, active networking also poses serious challenges that must be overcome for this technology to gain acceptance for use in telecom environments. A key challenge in this context is to develop a new concept for service creation and management. This article presents such a framework, based upon the concept of network visualization and on a generic service, which is called the Virtual Active Network (VAN) service. The VAN captures the functionality and resources a provider offers to a customer. The VAN provides a generic service abstraction for an active network environment. In traditional network environments, the customer has a simple service abstraction and perceives a service essentially as a black box with access points. In contrast, the VAN is a much more flexible service abstraction than today's virtual path or flow-based abstractions.

The article focuses on several ways through which virtual communities and software agents can be used to provide and locate trustworthy services on the Internet. There is an ongoing debate occurring among two main factions within the telecommunication industry. On one side are traditional telephone companies, who advocate intelligent networks with increased intelligence embedded within the network and controlled by the telecommunication providers. On the other side are proponents of stupid networks, who take their inspiration from the Internet. In this view as bandwidth becomes plentiful intelligence will propagate to edges of the network, the network itself will provide no more than bit transport. The boon with the stupid networks is that they support heterogeneity and extensibility. In this article, the problem of service location is considered. Authors studied the approach that places the intelligence in the end point that enables users to locate desirable services based on the trustworthy personalized recommendation of their peers.

Focuses on computer networks in the home or office in the United States as of March 1999. Reason for setting up a network; The example of Todd and Clare Thibodeaux in Arlington, Virginia; The Ethernet Local Area Network tailored for the layperson; Cisco and AT&T joining forces to provide home network equipment to its future cable modem subscribers; Plans of 3Com to introduce a line of home phone-line networking kits; Home networking for televisions, home security systems, and central air conditioning.

This article discusses the impact of computer networks' application in the field of education and learning in the U.S. Learning-in-doing is a model in which learners are increasingly involved in the authentic practices of communities through learning conversations and activities involving expert practitioners educators, and peers. A prototype example has been the National Geographic Society KidsNet Project, in which, children in thousands of elementary school classrooms investigated acid rain in their communities, pooled their data over networks, and carried out inquiries about why regional differences occurred in their data. The questions the students addressed were current concerns in scientific practice, and they learned scientific concepts, research strategies, data collection, and analysis technique through the doing of science rather than being taught about science observers. Network and multimedia technologies offer opportunities to increase the informational and interactional world of the learner through access to diverse databases, the possibility of collaborative projects with remote participants and access to a wide group of experts and others, with whom the learner can engage in conversation about a subject area, task, or project.

Presents several letters to the editor about class hierarchy inheritance, published in the January 1, 1993 issue of the journal "Communications of the ACM." Perspectives through which class hierarchy inheritance can be viewed; Characteristics of concept-oriented view of class hierarchy inheritance.

The article examines the chaotic behavior of digital signal processing networks using computer graphics. Chaos theory involves the study of how complicated behavior can arise in systems that are based on simple rules and how minute changes in the input of a system can lead to great differences in the output. Chaos theory today usually involves the study of a range of phenomena exhibiting a sensitive dependence on initial conditions. Chaotic behavior in such systems is generally irregular and disorderly. Examples include weather patterns, some neurological and cardiac activity and certain electrical networks of computers. Although chaos often seems totally random and unpredictable, it actually obeys strict mathematical rules derived from equations that can be formulated and studied. Digital signal processing is concerned with the representation of signals by sequences of numbers or symbols and the processing of these sequences in order to estimate characteristic parameters of a signal or transform a signal into a more desirable form.

The article focuses on the Cosmic Cube experimental computer for exploring the practice of computing. The Cosmic Cube is an experimental computer for exploring the practice of highly concurrent computing. The largest of several Cosmic Cubes currently in use at Caltech company consists of 64 small computers that work concurrently on parts of a larger problem and coordinate their computations by sending messages to each other. The article refers to these individual small computers as nodes. Each node is connected through bidirectional, asynchronous, point-to-point communication channels to six other nodes, to form a communication network that follows the plan of a six-dimensional hypercube, what is also known as binary 6-cube. An operating system kernel in each node schedules and runs processes within that node, provides system calls for processes to send and receive messages, and routes the messages that flow through the node. The excellent performance of the Cosmic Cube on a variety of complex and demanding applications and its modest cost and open-ended expandability suggest that highly concurrent systems of this type are an effective means of achieving faster and less expensive computing in the near future.

A broadcast packet is for delivery to all nodes of a network. Algorithms for accomplishing this delivery through a store-and-forward packet switching computer network include (1) transmission of separately addressed packets, (2) multidestination addressing, (3) hot potato forwarding, (4) spanning tree forwarding, and (5) source based forwarding. To this list of algorithms we add (6) reverse path forwarding, a broadcast routing method which exploits routing procedures and data structures already available for packet switching. Reverse path forwarding is a practical algorithm for broadcast routing in store-and-forward packet switching computer networks. The algorithm is described as being practical because it is not optimal according to metrics developed for its analysis in this paper, and also because it can be implemented in existing networks with less complexity than that required for the known alternatives. [ABSTRACT FROM AUTHOR]

An optimization procedure for the allocation of program and data flies in a computer network is presented. This algorithm takes into account the dependencies between files and programs such as occur in real heterogeneous computer networks. Insights into whether or not to convert programs from one computer 10 another can also be gained from the model. A search procedure for the file location problem is described, along with an example and a possible application of the model. [ABSTRACT FROM AUTHOR]

The article focuses on some of the important criteria for the gigabit technology to succeed. Advances in telecommunications and networking have been particularly notable in recent times. People have witnessed intense research resulting in fundamental information theory, coding and modulation, signal processing, flow and error control, packet and circuits witching, compression standards, local-area networks (LANs), distributed computing, Internet working, and finally, the World-Wide Web. The Internet, Public Telephone Switched Network (PSTN) and cable TV networks continue to deliver people's data, voice and video information as separate infrastructures. In the 1990s, a fundamental question remains that how can one integrate diverse network types and information types into a single gigabit/sec network. Performance is pushing network evolution that, in turn, is enabling creative new applications for its users. With the rapid introduction of fibre optics into telecommunication networks, a huge amount of potential bandwidth can be utilized.

Traditionally, efficient bandwidth sharing among multiple sessions has been at the heart of all packet networks. In conventional packet networks, bandwidth sharing was not a difficult problem, because of traffic homogeneity, lack of strict delay and bandwidth guarantee requirements, and presence of powerful flow control mechanisms. In ATM networks, bandwidth sharing becomes much more difficult to enforce for two reasons, the reactive flow and congestion procedures are gone, and multiple classes of traffic have different QOS requirements. Bandwidth sharing and statistical multiplexing in ATM have been studied extensively over the past decade, leading to several approximate analytic and simulation models that compute the equivalent bandwidth of a session when multiplexed with a given number of other sessions. The general outcome of these studies is that, while the homogeneous traffic case is relatively straightforward, the case of heterogeneous traffic sources is much more difficult to handle. In the latter case, the "equivalent bandwidth" computation is too time-consuming to be carried out in real time at call setup; furthermore, it is very sensitive to traffic parameters and to QOS requirements, which differ from class to class.

Discusses how the networked computing concept of the 1990s will make the next-generation of computers as active collaborators in the creation and acquisition of information. Development of new forms of computer networks; Changes in software applications; Hurdles that must be cleared before the advantages of networked computing can be fully realized; Importance of the technologies of handwriting and speech recognition.

Discusses the development of effective computer networks for advanced computing systems. History of the origins of computer networking; Details on the solution pioneered in the ARPANET computer network which is called packet switching; Dependence of the design of the communication network on the distances involved; Advantages of communication between identical types of computers; Details on the essential feature of the Ethernet.

The article presents the views of Gordon Bell, vice-president of Digital Equipment Corp., on developments in the computer industry and intercomputer communication. In the 1980s, users are expected to recognize a better interface for direct and indirect communication with their computers. Thus, the large computer population will force intercommunication and standardization among machines. The effect of minicomputers on the user population has been highly significant. Nearly all important features that minicomputers have such as floating-point and other data-type operations, paging and segmentation for better memory management and a reasonably large software library. Minicomputers are often connected to larger, more general purpose computers arranged at a higher level and thus, a hierarchy of computers can be created usually corresponding to hierarchies within the human organization. At present, programming languages are fundamentally special purpose and they solve problems within a particular context.

A technique for simulating the detailed logic networks of large and active digital systems is described. Essential objectives sought ore improved ease and economy in model generation, economy in execution time and space, and a facility for handling simultaneous activities. The main results obtained are a clear and useful separation of structural and behavioral model description, a reduction of manual tasks in converting Boolean logic into a structural model, the elimination of manual processes in achieving exclusive simulation of activity, an event-scheduling technique which does not deteriorate in economy as the event queue grows in length, and a simulation procedure which deals effectively with any mixture of serial and simultaneous activities. The passage of time is simulated in a precise, quantitative fashion, and systems to be simulated may be combinations of synchronous and asynchronous logic. Certain aspects of the techniques described may be used for the simulation of network structures other than digital networks. [ABSTRACT FROM AUTHOR]

The decomposition of a complex data transmission system into segments and the identification of the terminal configurations employed on each segment appear to offer promise as a powerful tool for permitting and clarifying measurements and comparisons of the performance of like system segments, and for describing the features of systems which are significant to performance measurements. Many problem areas remain, however, for further study. For example, the question of combining the individual performance measures of a multisegment, multi-mode-of-operation system into a meaningful measure of total systems performance appears quite formidable. It is the intent of the Task Group to approach these problems of performance measurement gradually and to resolve them first for the simpler systems before proceeding to complex system configurations. Although the techniques which this Task Group has evolved for system description may appear to be voluminous or even redundant when applied to very simple configurations, they are orderly, and every effort has been made to seek and exploit the "common denominators" of data transmission systems having arbitrary degrees of complexity. We doubt that much further compaction can be realized without, severely curtailing or destroying the generality and (hopefully) universal applicability of these methods. The format which has been described is admittedly incomplete. It is suggestive rather than exhaustive. It is believed that its chief virtue lies in the identification of an orderly succession of levels of abstraction which permits the regular decomposition of highly complex systems into functional subgroupings having a size structure within the span of human attention. The details of description outlined within these subgroupings require further study and elucidation and it will probably always be necessary for the system describer Io employ good judgment and imagination in extending the scope of description in those areas where new advances, unique applications and/or common sense so dictate. [ABSTRACT FROM AUTHOR]