Multicast Routing Protocols, Algorithms and its QOS Extensions

The advancement in optical fiber and switching technologies has resulted in a new generation of high-speed networks that can achieve speeds of up to a few gigabits per second. Also, the progress in audio, video and data storage technologies has given rise to new distributed real-time applications. These applications may involve multimedia, which require low end-to-end delay. The applications’ requirements, such as the end-to-end delay, delay jitter, and loss rate, are expressed as QoS parameters, which must be guaranteed. In addition, many of these new applications involve multiple users, and hence the importance of multicast communication. Multimedia applications are becoming increasingly important, as networks are now capable of carrying continuous media traffic, such as voice and video, to the end user. When there is a lot of information to transmit to a subset of hosts, then multicast is the best possible way to facilitate it. This article addresses different multicast routing algorithms and protocols. We have also discussed about the QoS multicast routing and conclude this article with mobile multicasting.

Moderator in Government-Initiated Online Discussions

In an older version of a Dutch Internet dictionary the moderator is defined as “a person who exercises censorship on a mailing list or newsgroup.”1 In the libertarian tradition of the Internet, moderation has often been viewed as conflicting with free speech and unrestrained communication (Tsagarousianou, 1998). However, as the history of the famous PEN-experiment (Public Electronic Network) in Santa Monica (1990-96) already showed, the free speech principle has to be weighed against other legitimate concerns, like the need to facilitate a genuine discussion and to counteract possible abuses of the medium (Docter & Dutton, 1998).

Mobile Location Services

The term “mobile era” as a characterization of the 21st century can hardly be considered an exaggeration (Kalakota & Robinson, 2001). Mobile phones are the fastest penetrating technology in the history of mankind, and global mobile phone ownership has surpassed even the ownership of fixed phones. Mobile applications, despite potentially being very different in nature from each other, all share a common characteristic that distinguishes them from their wire-line counterparts: they allow their users to move around while remaining capable of accessing the network and its services. In the mobility era, location identification has naturally become a critical attribute, as it opens the door to a world of applications and services that were unthinkable only a few years ago (May, 2001).

Mobile Commerce Technology

With the introduction of the World Wide Web, electronic commerce has revolutionized traditional commerce and boosted sales and exchanges of merchandise and information. Recently, the emergence of wireless and mobile networks has made possible the admission of electronic commerce to a new application and research subject—mobile commerce, which is defined as the exchange or buying and selling of commodities, services, or information on the Internet through the use of mobile handheld devices. With services provided by mobile commerce, consumers may use the microbrowsers on their cellular phones or PDAs to buy tickets, order meals, locate and book local hotel rooms, even write contracts on the move.

Migrating Legacy Systems to the Web

Business Process Reengineering (BPR) is defined as “the fundamental rethinking and radical redesign of business processes to achieve significant improvements of the performances, such as cost, quality, service, and speed” (Hammer & Champy, 1993). Most BPR projects aim at converting business organisations from hierarchical centralised structures to networked decentralised business units cooperating with one another. This conversion is assuming a strategic relevance as the Internet is changing radically business processes, not only because they are purposely reengineered, but also because the Internet and the information and communication technology, offer more convenient means of fulfilling their requirement.

Managing Strategic IT Investment Decisions

IT can have a significant impact on organizational performance, but it can also be a major inhibitor of change and can be a resource-hungry investment that often disappoints. Organizations can best influence the success of IT projects at the decision stage by rejecting poor ones and accepting beneficial ones. However, little is known about IT decision processes. Research demonstrates the importance of managing strategic IT investment decisions (SITIDs) effectively. SITIDs form part of the wider range of corporate strategic investment decisions (SIDs) that cover all aspects that the organization might wish to invest in. SIDs will then have different degrees of IT intensity that may impact on outcome. IT investment intensity is the degree to which IT is present in an investment decision. Here, IT investment intensity is defined as the ratio of IT spending to total investment. The higher IT investment intensity, the more important IT is to the whole investment. For example, Chou et al. (1997) find IT investment intensity to be negatively associated with SID effectiveness. The concept of IT intensity is similar to, but also somewhat different from, the concept of information intensity. Information intensity may be defined as the degree to which information is present in the product or service of a business (Porter & Millar, 1985).

Managing Hierarchies and Taxonomies in Relational Databases

The need to maintain classification and retrieval mechanisms that rely on concept hierarchies is as old as language itself. Familiar examples include the Dewey decimal classification system used in libraries and the system for classifying life forms developed in the 1700s by Carolus Linnaeus. A more recent example is Yahoo’s subject taxonomy.

Management of Cognitive and Affective Trust to Support Collaboration

Cognitive trust focuses on judgments of competence and reliability, and affective trust focuses on interpersonal bonds among individuals and institutions. Both cognitive and affective trusts play an integral role in organizations and institutions that rely on collaboration among individual members to achieve their goals and realize their vision.

Limited-Perspective Bias in Technology Projects

Limited-perspective bias is a human tendency to overestimate the completeness of what we know and to act on our own (limited) perspective of what is important (Moore & Burke, 2004a). In organizations, each person possesses a view that evolves from what he or she experiences and observes on a daily basis. Given one’s location or role in an organization, these views often differ and can affect one’s perspective on a problem or situation (O’Reilly & Pondy, 1979). Each individual perspective, however, is by and large “valid” in that it represents a distinct cognitive reality within that firm.

Life Cycle of ERP Systems

The 90’s witnessed an impressive growth of Enterprise Resource Planning (ERP) systems in the market of corporate IT solutions. For instance, O´Leary (2000) reports that a single ERP system (SAP´s R/3) is used by more than 60% of the multinational firms. Among the explanations for this phenomenon are the competitive pressures suffered by the companies that have forced them to seek alternatives for cost reduction, differentiation of products and services and integration of their business processes. The ERP systems evolved exploiting the need for quick deployment of integrated systems to meet these new business requirements, while companies were (and still are) under pressure to outsource all the activities that are not embraced by their core business.