Local Area Computer Network Research Articles

Modelling Reliability Characteristics of Technical Equipment of Local Area Computer Networks

Technical systems in the modern global world are rapidly evolving and improving. In most cases, these are large-scale multi-level systems and one of the problems that arises in the design process of such systems is to determine their reliability. Accordingly, in the paper, a mathematical model based on the Weibull distribution has been developed for determining a computer network reliability. In order to simplify calculating the reliability characteristics, the system is considered to be a hierarchical one, ramified to level 2, with bypass through the level. The developed model allows us to define the following parameters: the probability distribution of the count of working output elements, the availability function of the system, the duration of the system’s stay in each of its working states, and the duration of the system’s stay in the prescribed availability condition. The accuracy of the developed model is high. It can be used to determine the reliability parameters of the large, hierarchical, ramified systems. The research results of modelling a local area computer network are presented. In particular, we obtained the following best option for connecting workstations: 4 of them are connected to the main hub, and the rest (16) are connected to the second level hub, with a time to failure of 4818 h.

Pembagian jaringan komputer menggunakan virtual local area network guna mendukung perpustakaan digital

Digital libraries have been widely applied in educational institutions in Indonesia as a complement conventional libraries. The purpose of this research is to know division computer network access at the Adisutjipto Intitute of Technology (STTA) library. The research method used is a qualitative method using Prepare Plan Design Implement Operate and Optimize (PPDIOO). The result research is that people who have internet access will not be able to enter the digital library network. Computer network users who want to access digital libraries must log into the computer network that provides digital books in the library using a Virtual Local Area Network (VLAN). Making this VLAN requires a computer network infrastructure in the form of a Local Area Network (LAN) and computer network equipment in the form of a switch that can be used to configure multiple VLANs in a LAN. Some of the existing services in the library are placed on one VLAN and the digital library is placed on another VLAN. From the test results, it can be seen that between computers that provide services in the library on VLAN 2 cannot communicate via the connecting network to VLAN 1 where the digital library with website based services will be located. This is evidenced by the ping command which generates request time out information. VLANs network in the STTA library have been able to provide support for plans to improve services to members and academicians in the form of a digital library.

SIMULATION OF LOCAL AREA COMPUTER NETWORKS WITH DISTANCE-VECTOR ROUTING PROTOCOLS FOR THE NEEDS OF THE PRIVATE COMPANY

In this paper a simulation of local area computer networks for the needs of the private company is made.

ВИКОРИСТАННЯ ЛОКАЛЬНОЇ МЕРЕЖІ ДЛЯ КОНТРОЛЮ ТЕМПЕРАТУРИ ТА ВОЛОГОСТІ ПОВІТРЯ

The devices for access to computer local area networks construction features, with microcontrollers and single chip ethernet interfaces, company microchip enc28j60 and enc424j600 chips utilization are examined

Computer Local Area Network Security and Management

Development of computer network technology has greatly improved the sharing rate and utilization of information resources, many areas are widely used local area network, widely used degree gradually expose their security and confidentiality issues. In particular, people lack knowledge on security policy and network security control mechanisms, leading network security becomes more complex. In this paper, the main problem with the current computer Local Area Network security and the starting point, the focus of the analysis and management of their security and confidentiality measures, hope to further enhance the computer LAN security.

On the Maintenance Management and Network Security of Local Area Network

With the development of the science and technology of the computer application, the maintenance management and the security of the computers is an important problem. In this paper the author presents his own opinions on these issues. Therefore, the maintenance management of the computer local area network is very important to guarantee the security and stability of the network and to the use of the cyber sources to a maximum.

A novel tri-band multiple input multiple output antenna with improved bandwidth and isolation

A novel multislot patch antenna operating from 3.5–5.9 GHz is proposed for a two element multiple input multiple output (MIMO) system. The developed system resonates at the tri-band of frequencies 2 GHz, 4.2 GHz, and 5.5 GHz, giving an impedance bandwidth of 51% at 10 dB return loss and a reduced mutual coupling less than −50 dB. The enhancement of the bandwidth and the reduction of the mutual coupling are achieved using the reduced ground plane and unique symmetric slot structure. The proposed MIMO system can be used for high speed wireless computer local area networks and WiMAX applications. The measured results are found in good agreement with the simulation results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2766–2770, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27178

Managing a High Speed LAN using Distributed Artificial Intelligence

This study is concerned with a practical application of distributed artificial intelligence for managing the high data rate bus structured local area computer network that uses deterministic multiple access protocol. In the selected network that is managed using distributed artificial intelligence, the dynamic sharing of the available bandwidth among stations is achieved by forming train to which each station may append a packet after issuing a reservation. Reservation and packet transmissions are governed by the reception of control packets (token) issued by the network end stations. Managing approach that was suggested depends on using intelligent autonomous agents, which are responsible for various tasks among it: election of the end stations, the recovery from failures, and the insertion of new stations in the network. All these tasks are based on the use of special tokens.

E-Shaped Patch Antennas for High-Speed Wireless Networks

Thin, broad-band, E-shaped microstrip patch antennas (ESPAs), operating in the 5-6 GHz frequency range, are presented. They are intended for high-speed (IEEE 802.11a, 54 Mb/s) wireless computer local area networks (WLAN) and other wireless communication systems. They are suitable for WLAN adaptor cards in the PCMCIA (also known as PC) format, allowing users of current notebook computers to upgrade to this high-speed wireless standard at a low cost. Importantly, our antennas are thin enough to be accommodated in a PCMCIA card of standard 5-mm thickness, without making the antenna end thicker than the card itself. Two different closely spaced antenna pairs are also presented for diversity. A new ESPA configuration with a microstrip feed is presented for easy integration with microwave transceivers. In all cases, within the two IEEE 802.11a WLAN bands (5.15-5.35 GHz and 5.725-5.825 GHz), the reflection coefficient at the antenna input is <-10 dB and in both antenna pairs, mutual coupling between the two antennas is <-20 dB.

B07: Aho-Corasick algorithm implementation in hardware for network intrusion detection

One of the main objectives for pattern matching methods study is their serious role in the real-world applications, for example in a branch of Network Intrusion Detection Systems. A NIDS purpose is to protect a local area computer network from unauthorised access. This paper considers a new implementation of the classical Aho-Corasick pattern matching algorithm in hardware. Presented results show that the Aho-Corasick algorithm gives efficient utilization of resources (memory and logic cells) at the cost of lower throughput.

Embed with Forth

WARNING: Any reader with a tendency to technoparanoia should stop here and go no further! Information of a potential anxiety-provoking nature follows. Those persons not afraid of hidden, invisible computer systems are free to continue reading. In October, 1995 I attended the ACM OOPSLA conference in Austin, Texas. The OOPSLA organizers were kind enough to allow me to present a 45 minute robotics demonstration twice, on Wednesday the 18th and Thursday the 19th [1]. This presentation described techniques for object oriented design as well as object oriented programming, with Forth being the high level language used (with OOP extensions). I showed the attendees my (then new) artificial hand design which utilized a distributed multiprocessor network for control from a central artificial "brain". The demonstration was well-attended each day. I'm sure this presentation upheld the finest OOPSLA traditions for systems design and programming, since several people told me so afterwards. Except one person. He took me aside after the second demo and loudly questioned why I was at the conference at all. His argument, literally and figuratively, was not only with the Forth language (I've heard that before) but with embedded systems programming in general. He was a desktop systems application programmer, and thought that only that kind of work was an acceptable exercise of intellectual talents. I was shocked by this attack, especially since there was no way he and I might ever be in competition for the same job or income source. We just did different things, under the general umbrella of computing applications. My advice to him and all other persons who disapprove of embedded computer systems is: get used to it! In terms of instantiations of application designs, embedded/hidden systems outnumber desktop systems by a huge margin: around 100 to 1 [2]. They're everywhere, and you really don't want to be without them. Little computers are even hidden inside your desktop workstation (for example, in the keyboard, the motherboard, the plug-in accessory cards, the disk drives and the display unit). They make your video games work, and your Palm Pilot PDA, your CD player, your TV, your washer and dryer, your telephone, your car, your house, the traffic lights, your power company, pretty much everything. By clever design, you are made aware of almost none of this. One of my favorite examples of this technology: the 1990's Mitsubishi Gallant. It had several computers, for the engine management system, shock absorber control, antilock braking and the automatic transmission. They all communicated with each other in real time. When the driver would go into a turn at a good rate of speed, the Gforce sensors would stiffen the shock absorber settings on the outside of the turn, the automatic transmission would hold the currently selected gear (inhibiting up or downshifting), the antilock wheel sensors would detect wheel slippage and the engine control system would modulate power to reduce the possibility of vehicle spinout. All the driver noticed was that at low speeds the Mitsu drove like a Cadillac, and when pushed harder it drove like a Corvette. No driver attention to these systems was required. This trend has continued apace. In the 1990's a typical Porsche had more than 60 microcontrollers per car. A current Audi exceeds 80 microcontrollers per car. The Jaguar has become a rolling computer local area network (not including navigation systems, GPS, embedded cell-phones and DVD-CD entertainment). The weight of wiring in cars has decreased; the mass of silicon chips has increased. The appetite for embedded controllers in all products seems bottomless.

Asymptotic behavior of nonlinear networked control systems

The defining characteristic of a networked control system (NCS) is having a feedback loop that passes through a local area computer network. Our two-step design approach includes using standard control methodologies and choosing the network protocol and bandwidth in order to ensure important closed-loop properties are preserved when a computer network is inserted into the feedback loop. For sufficiently high data rates, global exponential stability is preserved. Simulations are included to demonstrate the theoretical result.

Advances in Navy Pharmacy Information Technology: Accessing Micromedex via the Composite Healthcare Computer System and Local Area Networks

The pharmacy profession has long used technology to more effectively bring health care to the patient. Navy pharmacy has embraced technology advances in its daily operations, from computers to dispensing robots. Evolving from the traditional role of compounding and dispensing specialists, pharmacists are establishing themselves as vital team members in direct patient care: on the ward, in ambulatory clinics, in specialty clinics, and in other specialty patient care programs (e.g., smoking cessation). An important part of the evolution is the timely access to the most up-to-date information available. Micromedex, Inc. (Denver, Colorado), has developed a number of computer CD-ROM-based full-text pharmacy, toxicology, emergency medicine, and patient education products. Micromedex is a recognized leader with regard to total pharmaceutical information availability. This article discusses the implementation of Micromedex products within the established Composite Healthcare Computer System and the subsequent use by and effect on the international Navy pharmacy community.

Wavelength Division Multiplexing Systems and Networks

Expanding the channel capacity is the pressing need of today's communication systems. Multiplexing is the technique of combining channels to achieve this without interference. Wavelength-division-multiplexed (WDM) systems and networks are currently being investigated for optical data transmission in telecommunication and computer local area networks etc, with a view to utilize the potential of high bandwidth of such system and networks. This paper reviews some basic wavelength division multiplexed optical systems and networks and their applications.

On The Throughput Of A Partitioned Local Area Computer Network

A new switch connection Approach to improve the performance of large token bus networks is devised. The single large token bus network is partitioned into smaller networks, and these networks are interconnected by a multi-stage butterfly switch. This technique has enhanced the performance of the network by increasing the throughput and reducing the average packet delay. The performance of the single large network and the proposed partitioned network have been modelled and simulated using Simscript II.5. It was found that the throughput of the proposed partitioned network is improved and there is a significant decrease in the average packet delay compared to the single network.

New Vehicle Data Bus Architecture and In-Vehicle Information System Evaluation Platform for Intelligent Transportation Systems Modules

An increasing number of intelligent transportation systems- (ITS-) after-market systems present a set of in-vehicle installation and use problems relatively unique in the history of automobile use. Many automobile manufacturers would like to offer these new state-of-the-art devices to customers, but are hampered by the current design cycle of new cars. While automobile manufacturers are indeed using multiplex buses [the automotive equivalent of a computer local area network (LAN)], problems remain because manufacturers are not converging on a single bus standard. A new dual-bus architecture to address these problems is presented with an in-vehicle information system (IVIS) research platform on which the principles embodied in the ITS data bus architecture can be evaluated. The dual-bus architecture has been embodied in a proposed Society of Automotive Engineers (SAE) standard, with support from both automobile and consumer electronics manufacturers. The architecture and a reference model for the interfaces and protocols of the new bus are presented and described. The goals of the ITS data bus are to be inexpensive and easy to install, and to provide for safe and secure functioning. These high-level goals are embodied in the proposed standard. The IVIS development platform comprises a number of personal computers (PCs) linked via ethernet LAN, with a high-end PC serving as the IVIS computer. In this LAN, actual devices can be inserted in place of the original PC that emulated them. This platform will serve as the development and test bed for an ITS data bus conformity test, the SAE standard for which is also being developed.

Remote connection to the Kyushu University Medical Center LAN using digital and analog telephone lines.

SOHO (Small Office/Home Office) has recently become popular, as it makes working at home possible. Computers or Local Area Networks(LAN) connected to the office network from home are necessary for the implementation of this concept. Kyushu University has begun a service connecting home computers to the campus LAN for researchers, staff and students of the Faculty of Medicine. We have two different telephone connection methods. One connects the campus LAN and the home computer LAN using routers through the Integrated Services Digital Network (ISDN). The other connects computers at home to the workstation in the university, using modems and the PPP (Point to Point Protocol) through a public telephone analog line. This paper outlines our university SOHO connection system and discusses the merits and demerits of using telephone line connections.

Parallel processing of chemical information in a local area network—II. A parallel cross-validation procedure for artificial neural networks

This paper describes a parallel cross-validation (PCV) procedure, for testing the predictive ability of multi-layer feed-forward (MLF) neural networks models, trained by the generalized delta learning rule. The PCV program has been parallelized to operate in a local area computer network. Development and execution of the parallel application was aided by the HYDRA programming environment, which is extensively described in Part I of this paper. A brief theoretical introduction on MLF networks is given and the problems, associated with the validation of predictive abilities, will be discussed. Furthermore, this paper comprises a general outline of the PCV program. Finally, the parallel PCV application is used to validate the predictive ability of an MLF network modeling a chemical non-linear function approximation problem which is described extensively in the literature.

Development of a toxicologic pathology system using personal computer network.

An integrated toxicologic pathology system named “MacMic” has been developed and expanded for use in toxicological studies. By utilizing a personal computer Local Area Network (LAN), high user interface and easy data sharing were achieved at low cost. The studies covered by this system are all of the general toxicological studies including carcinogenicity studies. It was designed for the purpose of easy handling from the standpoint of pathologists, and it offers high usability. At histopathological examinations, screeners can refer to the data entered from other subsystems: body/organ weight measurement, urinalysis, hematology, and blood chemistry, and also those data summaries, which clarify the differences at a given rate from controls by different color. Entry of gross and histological findings is done by referring to the specialized dictionaries, which are maintained routinely, and the selection of the findings and copy from those entered before are easy. Movement to the next step is quick with function keys, and the proceeding status of histological examinations is obvious with a key for fixing and color distinction. There is a memo function for communication between screeners and exclusive control function to allow multiple access to the same study but not to the same organ at a time for protection of data. “MacMic” was originally the system using personal computer LAN for a certain laboratory, but it was found to be applicable to other laboratory/institute.

Restructuring Classroom Interaction with Networked Computers: Effects on Quantity and Characteristics of Language Production

This study describes the use of Daedalus InterChange, a local area computer network application, to facilitate communicative language use through synchronous, written classroom interaction. The study compares the quantity and characteristics of the discourse produced by two groups of second‐semester French students during an InterChange session and during an oral class discussion on the same topic. Students had over twice as many turns, produced two to four times more sentences, and used a much greater variety of discourse functions when working in InterChange than they did in their oral discussion. Furthermore, the distribution and direction of turns were radically different in the two conditions, with much more direct student‐to‐student exchange in the InterChange condition. Students' and instructors' responses to using InterChange were assessed: both groups responded favorably, although students more enthusiastically so than the instructors. Features of InterChange that may be unsettling for teachers include: decentering of teacher authority, lesser attention to grammatical accuracy, and less clear coherence and continuity of discussions.