Packet-switched Computer Networks Research Articles

Edge Cryptography and the Codevelopment of Computer Networks and Cybersecurity

Developed around 1973 by BBN under contract from DARPA, the private line interface (PLI), a cryptographic cybersecurity device used on the Arpanet, operated with minimal modification of the existing network infrastructure, sitting at the edge of the network between the network switches and the connected host computers. As a result of the developmental and infrastructural trajectory set in motion by the PLI, significant cryptographic resources remain at the edges (or ends) of the networks that constitute the Internet today. This study of the PLI is an entry into the historical relationship between cryptography and packet-switched computer networks.

In the Shadow of ARPANET and Internet: Louis Pouzin and the Cyclades Network in the 1970s

During the 1970s, French engineer Louis Pouzin led a small team of researchers who designed an experimental packet-switching computer network they named “Cyclades.” Despite the technical successes of Cyclades—especially Pouzin’s “datagram” concept that was adopted by the American networking researchers Vinton Cerf and Robert Kahn—the French authorities starved Cyclades by 1979 and split up Pouzin and his team. This article describes the opportunities that the Cyclades group pursued and the obstacles it encountered in its efforts to cooperate with peers in the United States, France, and Europe. Rather than squeezing Pouzin and Cyclades into a teleological narrative that seeks only to explain the rise of the Internet, the article suggests that its broader rubric of “networking history” allows historians to recover the political and human complexities of digital convergence—such as the bold words and disruptive work of Louis Pouzin.

New Results in Generalized Minimum Variance Control of Computer Networks

In this paper new results in adaptive (generalized) minimum variance control of packet switching computer networks are presented. New solutions, corresponding to the new inverses of the nonsquare polynomial matrices, can be used for design of robust control of multivariable systems with different number of inputs and outputs. Application of polynomial matrix inverses with arbitrary degrees of freedom creates the possibilities to optimal control of computer networks in terms of usage their maximal bandwidth. Simulation examples made in Matlab environment show big potential of presented approach. DOI: http://dx.doi.org/10.5755/j01.itc.43.3.6268

Integrating mitosis, toxicity, and transgene expression in a telecommunications packet-switched network model of lipoplex-mediated gene delivery.

Gene delivery systems transport exogenous genetic information to cells or biological systems with the potential to directly alter endogenous gene expression and behavior with applications in functional genomics, tissue engineering, medical devices, and gene therapy. Nonviral systems offer advantages over viral systems because of their low immunogenicity, inexpensive synthesis, and easy modification but suffer from lower transfection levels. The representation of gene transfer using models offers perspective and interpretation of complex cellular mechanisms,including nonviral gene delivery where exact mechanisms are unknown. Here, we introduce a novel telecommunications model of the nonviral gene delivery process in which the delivery of the gene to a cell is synonymous with delivery of a packet of information to a destination computer within a packet-switched computer network. Such a model uses nodes and layers to simplify the complexity of modeling the transfection process and to overcome several challenges of existing models. These challenges include a limited scope and limited time frame, which often does not incorporate biological effects known to affect transfection. The telecommunication model was constructed in MATLAB to model lipoplex delivery of the gene encoding the green fluorescent protein to HeLa cells. Mitosis and toxicity events were included in the model resulting in simulation outputs of nuclear internalization and transfection efficiency that correlated with experimental data. A priori predictions based on model sensitivity analysis suggest that increasing endosomal escape and decreasing lysosomal degradation, protein degradation, and GFP-induced toxicity can improve transfection efficiency by three-fold. Application of the telecommunications model to nonviral gene delivery offers insight into the development of new gene delivery systems with therapeutically relevant transfection levels.

Routing, Scalability, Reckoning Effort, Large Networks, Quality of Service, Network Seclusion

Stochastic systems play a prominent role in computer graphics, because of their success in modeling a variety of complex and natural phenomena. Routing plays a vital role on the performance and functionality of computer networks. Routing networks means identifying a path in the network that optimizes a certain criterion which is called as Quality of Service (QoS) routing. The main aim of seclusion is minimizing the reckoning effort by maximizing the probability of having a path between source-destination pairs in the network. This paper deals with the specification and analysis of routing procedures which are effective for large hoard and promote packet switched computer networks. The new concept of stochastic seclusion method is introduced to resolve the scalability in QoS routing algorithm. A queue discipline in multiclass network is analyzed. An optimization algorithm is designed for seclusion strategy using stochastic technique in which the routing functions in the network are being increased. Numerical calculations and graphical representation shows that the proposed method improves the performance measure in terms of reduction in reckoning effort. Keywords: Routing, Scalability, Reckoning Effort, Large Networks, Quality of Service, Network Seclusion

Stochastic Divination of Reckoning Enactment on Multi Class Queuing System

Stochastic systems play a prominent role in computer graphics, because of their success in modeling a variety of complex and natural phenomena. Routing plays a vital role on the performance and functionality of computer networks. Routing networks means identifying a path in the network that optimizes a certain criterion which is called as Quality of Service (QoS) routing. The main aim of seclusion is minimizing the reckoning effort by maximizing the probability of having a path between source-destination pairs in the network. This paper deals with the specification and analysis of routing procedures which are effective for large hoard and promote packet switched computer networks. The new concept of stochastic seclusion method is introduced to resolve the scalability in QoS routing algorithm. A queue discipline in multiclass network is analyzed. An optimization algorithm is designed for seclusion strategy using stochastic technique in which the routing functions in the network are being increased. Numerical calculations and graphical representation shows that the proposed method improves the performance measure in terms of reduction in reckoning effort.

The Birth of Link-State Routing

‘‘Routing is a hard problem.’’ That’s what colleagues told me when I joined BBN in 1971, right after getting my undergraduate and master’s degrees in computer science at Harvard University. As a student, I had built the hardware and software to connect Harvard’s first interactive computer, the DEC PDP-1, to the infant Arpanet (the first packet switching computer network and precursor of the Internet). I had also taken a Harvard course taught by two senior BBN engineers who built the original interface message processors (IMPs), the switching nodes that routed traffic across the network. While at BBN, and with almost all the course requirements for a PhD in hand, it was time to find a possible dissertation topic. So I was glad to learn that dynamic routing—determining the best paths for network traffic in real time—was considered a difficult computer science issue because I planned to tackle it. By 1971, the Arpanet had been up and running long enough to disclose shortcomings in the performance and stability of the original design. My job at BBN was to redesign and rewrite all the software for the IMP, not just the routing module. I fondly recall releasing new IMP software to the whole network (amounting to a few dozen nodes at the time) every other Tuesday morning for two years. Fifty software versions later, the IMPs had more stable congestion management, better reliability, and higher throughput. But routing still remained a challenging area for further study. By the end of 1974 I had completed my PhD dissertation for Harvard on routing while working full-time at BBN. This dissertation described the problem, analyzed and compared many routing algorithms, and pointed out topics for further work, such as hierarchical routing for networks of networks. But I had not resolved some of the nagging network accidents, outages, and other crises caused by the original Arpanet routing system.

Guaranteed servicing in computer networks: Models and realization scenarios

Consideration was given to the guaranteed servicing in the packet-switched computer networks. The existing network equipment was analyzed. Approaches to and scenarios of the guaranteed servicing under the least requirements on the network equipment were proposed on the basis of the constructed formal packet-switched model and analysis of the existing network equipment.

Discrete capacity and flow assignment algorithms with performance guarantee

The joint problem of selecting routing and a capacity value for each link in networks is considered. We apply an alternative approach for some models that have been addressed to (store-and-forward) packet-switched computer network discrete capacity allocation and routing problems. The network topology and traffic characteristics are supposed to be given. The goal is to obtain a feasible solution with minimum total cost, where the total cost include both leasing capacity and congestion costs. Heuristic algorithms with performance guarantee based on lower bounds and on the separability of the objective function are proposed. Experiments were conducted to verify the performance and to confirm the efficiency of the proposed algorithms.

Neural network based optimal routing algorithm for communication networks

This paper presents the capability of the neural networks as a computational tool for solving constrained optimization problem, arising in routing algorithms for the present day communication networks. The application of neural networks in the optimum routing problem, in case of packet switched computer networks, where the goal is to minimize the average delays in the communication have been addressed. The effectiveness of neural network is shown by the results of simulation of a neural design to solve the shortest path problem. Simulation model of neural network is shown to be utilized in an optimum routing algorithm known as flow deviation algorithm. It is also shown that the model will enable the routing algorithm to be implemented in real time and also to be adaptive to changes in link costs and network topology.

A geographic perspective on commercial Internet survivability

The earliest predecessor to the commercial Internet of today was ARPANET, a packet switched computer network developed by the US Defense Department’s Advanced Research Projects Agency. Designed to withstand a nuclear attack, ARPANET utilized a deurbanized, decentralized, and distributed network topology. As ARPANET gradually evolved into NSFNET and eventually the commercial Internet, increasing traffic, demands for interconnection, and growing private interests required the movement from a distributed network topology to a more economically viable network configuration, hub-and-spoke. Although transmission speeds and capacities of today’s commercial Internet clearly surpass those of its predecessors, the economics of network survivability and reliability have also become more relevant. With thousands of businesses, corporations, universities, and governments relying on the Internet for day-to-day functions, major disruptions in service have the potential to be economically catastrophic. This paper explores the network topology of the commercial Internet, with a focus on network survivability. GIS based approaches are used to simulate both nodal and link failure in the US commercial backbone system in order to assess potential impacts. Results suggest that many of the larger metropolitan benefit from robust network infrastructure, while smaller cities are more prone to service disruptions.

The shortest path computation in MOSPF protocol using an annealed Hopfield neural network with a new cooling schedule

Many network services, such as video conferencing and video on demand, have popularly used the multimedia communications. The attached hosts/routers are required to transmit data as multicasting in most multimedia applications. In order to provide an efficient data routing, routers must provide multicast capability. In this paper, a new cooling schedule in Hopfield neural network with annealing strategy is proposed to calculate the shortest path (SP) tree for multicast open shortest path first (MOSPF) protocol. The SP tree in multicast is built on demand and is rooted at the source node. To facilitate the hardware implementation, the annealed Hopfield neural network could be a good candidate to deal with SP problems in packet switching computer networks. In addition, it is proved that the proposed new cooling schedule is more suitable in all range of fixed temperature than the other demonstrated cooling schedules in the experimental results.

The Revolution Will Not Be Televised: Introduction to the Special Issue on Marketing Science and the Internet

There is a revolution happening—a startling and amazing revolution that is altering everything from our traditional views of how advertising and communication media work to how people can and should communicate with each other. That revolution is the Internet—the massive global network of interconnected packet-switched computer networks—and as the most important innovation since the development of the printing press, the Internet has the potential to radically transform not just the way individuals go about conducting their business with each other, but also the very essence of what it means to be a human being in society. Since the introduction of the first graphicallyoriented Web browser, Mosaic, in 1993, the Internet has experienced phenomenal growth, both in terms of the number of computers and devices connected to it and the number of individuals and firms providing and accessing content on it (Hoffman et al. 2000). The first significant commercial activity appeared on the Web by 1994and in the ensuing five years, the commercialization of the Internet has exploded. There are now very few countries and territories left in the entire world that do not have at least one host computer connected to the Internet (Rutkowski 1999). At the same time, electronic commerce, as a research area, a business, and, indeed, an entire new industry, is still very much in its infancy. There is much confusion and complexity and not nearly enough solid information.

A 32-channel tunable receiver module for wavelength-division multiple-access networks

We report the realization of a 32-channel tunable optical receiver module for packet-switched multiwavelength computer networks. The tunable receiver consists of a planar array waveguide grating demultiplexer, photodetector array and followed by selectable receivers. The channel selection is based on sequential switching of the received optical signals in stages at the analogue level. Typical receiver sensitivity is -24 dBm at 10/sup -9/, using a 700-Mb/s nonreturn-to-zero (NRZ) pseudorandom binary sequence (PRBS). The channel switching time is /spl sim/40 ns.

An evolutionary approach for configuring economical packet switched computer networks

The topological design of computer networks essentially consists in finding a network topology which minimizes the communication costs, taking into account some constraints such as performance and quality of service. This optimization problem is well known as difficult to solve, such that only heuristic methods are usually recommended and used. These methods are incremental in the sense that they take a starting topology as input solution and perturb it in order to produce a better solution. In this paper, we propose an evolutionary approach, based on the genetic algorithm paradigm, for solving this problem. Simulation results confirm the appropriateness and efficiency of this approach which yields solutions of very good quality for moderate size networks.

A new methodology for generating rules in the topological design of computer networks

The topological design problem consists in finding network topologies which satisfy a set of performance criteria at the lowest cost. This problem inherently bears the risk of combinatorial explosion, and therefore requires the use of heuristic methods. More specifically, one such approach uses a knowledge-based system allowing the application of a set of rules, called perturbation rules, to a starting topology, in order to reduce the total cost of the links or to restore a delay constraint. Acquiring these perturbation rules constitutes one of the most important aspects of this approach, which essentially attempts to reduce the search space of candidate topologies. This paper focuses on the development of a sound methodology for generating such rules. Experimental results confirm the adequacy and effectiveness of the rules induced by this methodology in the context of dimensioning reliable packet-switched computer networks.

A taxonomy for congestion control algorithms in packet switching networks

The authors propose a new taxonomy for congestion control algorithms in packet switching computer networks based on control theory. They view a network as a large, distributed control system, in which a congestion control scheme is a (distributed) control policy executable at each node (host or switches) of the network in order to a certain level of stable conditions. This taxonomy provides a coherent framework for the comparative study of existing algorithms and offers clues toward the development of new congestion control strategies. >

Neural networks for shortest path computation and routing in computer networks

The application of neural networks to the optimum routing problem in packet-switched computer networks, where the goal is to minimize the network-wide average time delay, is addressed. Under appropriate assumptions, the optimum routing algorithm relies heavily on shortest path computations that have to be carried out in real time. For this purpose an efficient neural network shortest path algorithm that is an improved version of previously suggested Hopfield models is proposed. The general principles involved in the design of the proposed neural network are discussed in detail. Its computational power is demonstrated through computer simulations. One of the main features of the proposed model is that it will enable the routing algorithm to be implemented in real time and also to be adaptive to changes in link costs and network topology.

A queueing system with group service and returning calls

We consider a mathematical model of the data channel in a packet-switching computer network with a pipeline protocol.

Simulation of congestion avoidance and routing in packet switching networks

The development of a flexible computer simulation package for packet switching computer networks that enables the evaluation of different congestion avoidance methods and routing strategies is discussed. The package is presented in terms of the factors involved, the operations required, and the simulation execution considerations. Use of the package for the evaluation of congestion avoidance methods and routing strategies is described. The congestion avoidance methods considered include isarithmic methods with static and dynamic control. In addition, static and dynamic routing strategies are taken into account. The relative differences between the various methods and strategies considered are presented. It has been found that the results obtained agree with previous results, and this confirms the suitability of the package for future investigation. The package would be useful to students and researchers in the field, especially since it uses the widely known computer language Pascal, and is run on an IBM PC(AT).