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Internet in the Kingdom of Saudi Arabia was introduced in the late 1990s. Being relatively new, its effects and impact on Saudi society are still in their infancy. A survey-based study was conducted to measure these effects, monitor their influence, project possible long-term develop-ments, and define early measures that would best harness this new technology. Covering a span of two years, this study also identifies and documents any noticeable shifts in perspectives. This work presents the findings and observations drawn from this study and is based on the direct interpretation and cross-analysis of survey responses.

Users of parallel machines need to have a good grasp for how different communication patterns and styles affect the performance of message-passing applications. LogGP is a simple performance model that reflects the most important parameters required to estimate the communication performance of parallel computers. The message passing interface (MPI) standard provides new opportunities for developing high performance parallel and distributed applications. In this paper, we use LogGP as a conceptual framework for evaluating the performance of MPI communications on three platforms: Cray-Research T3D, Convex Exemplar 1600SP, and a network of workstations (NOW). We develop a simple set of communication benchmarks to extract the LogGP parameters. Our objective in this is to compare the performance of MPI communication on several platforms and to identify a performance model suitable for MPI performance characterization. In particular, two problems are addressed: how LogGP quantifies MPI performance and what extra features are required for modeling MPI, and how MPI performance compare on the three computing platforms: Cray Research T3D, Convex Exemplar 1600SP, and workstations clusters.

In this paper, we consider fault-tolerant routing algorithms in hypercube multicomputer networks. In particular, one of the most quoted adaptive fault-tolerant routing algorithm for hypercubes in the literature is studied in detail and its limited ability to route messages in the presence of some fault patterns (i.e., combination of node and link faults), is pointed out. A modified algorithm is proposed and its performance, using simulation, is compared to that of the above mentioned algorithm. It is shown that the proposed algorithm outperforms the existing one in terms of its ability to route routable messages around the hypercube in the presence of node and/or links faults. This improvement is achieved while using the same average path length or even improving it. Illustrative examples are shown in support of such improvement.

The processing and the communication capacities of interconnected workstations are currently not prohibitive for executing parallel and distributed applications. The programs can be executed on remote workstations yet deliver the results locally or where they are required, provided the overhead is tolerable. This capability opens up a whole new era. With a task (or process) migration facility, it would be possible to utilize abundant processing power and realize fail-proof execution of applications. This paper presents a task migration infrastructure (TMI), which allows tasks to dynamically migrate amongst the workstations. It incorporates parallel and distributed applications. Contrary to other studies, TMI is partly integrated into the UNIX kernel in the form of enhancements (E-kernel) and it is based on a dedicated message passing communication interface. TMI is to serve as an infrastructure for higher level usage such as fault tolerance, load balancing, and resource utilization. The experimental results have acknowledged the feasibility of TMI, in particular for long running applications.

The growing demand for high processing power in various scientific and engineering applications has made multiprocessing architectures increasingly popular. These multiprocessing systems consist of processing elements or nodes which are connected together by interconnection networks in various topologies. One of the design methodologies used for parallel machines has fed to the development of distributed memory message-passing concurrent computers, commonly known as multicomputers. They consist of many processing nodes that interact by sending messages (containing both data and synchronization information) over a communication link, between nodes. Thus, efficient communication in multicomputers is one of the important research areas in parallel computing today, and it depends on the underlying scheme for routing. For this reason it is essential to know which routing techniques are suitable and practical. Although an extremely wide number of routing algorithms have been proposed and implemented in hardware and software, it is difficult for the designer of a multicomputer to choose the best routing algorithm given a particular architectural configuration. In an attempt to overcome this difficulty, we present a survey and comparison of wormhole routing techniques in mesh interconnection networks. The mesh topology is important because of its scalability. Moreover, it has already been implemented in many commercial multicomputers.

Among one of the most far-reaching influences of the Internet, especially from the perspective of business and market models, is the concept and application of eCommerce. Today, this erstwhile ‘experimental’ commerce model has become a standard platform for streamlining business flows and broadening product outreach. This is validated by the significant emphasis by a number of countries in developing robust eCommerce architectures tailored to suit their economical-social systems. An interesting case study in this perspective is the Kingdom of Saudi Arabia, especially given its emphasis on local, regional and religious traditions. Presently, with a tremendous growth rate in Internet connectivity, the Kingdom is actively moving towards large-scale adoption of eCommerce systems. In 2001, a two year project was initiated to study the present influence of Internet on social, educational and business systems within the Kingdom. One of the major aspects was the analysis of user responses collected over the two-year period through a number of surveys, which were designed based on two prominent behavioural models: Theory of Planned Behaviour and Roger’s Theory of Diffusion of Innovations. The consequent analysis of the results was supported and in some cases verified with linear regression models. This paper reports on the consequent findings, which identify factors that may significantly affect the adoption of eCommerce in the Kingdom.

Many large-scale multicomputers communicate through message passing. This makes the design of the underlying network is a crucial issue for multicomputers. Many interconnection networks have been proposed and studied, but none has been shown to be universally applicable. A sizeable performance improvement may be possible by combining the features of two or more types of interconnection network architectures. Also, as the system size increases, there is a locality of communication among the processors which can be exploited for performance gains. Hierarchical networks provide a means to achieve both these performance improvements. In this paper, we propose a new hierarchical fault-tolerant interconnection network that combines the hypercube and the torus. Simulation results show that the fault coverage and mean internodal distance for the proposed network are better than those achieved by both the hypercube and the torus.

LogGP is a simple parallel machine model that reflects the important parameters required to measure the real performance of parallel computers (Alexandrov et al., 1995). The message passing interface (MPI) standard provides new opportunities for developing high performance parallel and distributed applications. We use LogGP as a conceptual framework for evaluating the performance of MPI communications on three platforms: Cray-research T3D, Convex Exemplar 1600, and a network of workstations (NOW). Each machine is viewed as a "black box" that supports the same MPI implementation.