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No description available.

This paper describes a Protocol Finite State Machine (PFSM) for implementing communication protocols. Our objective is to develop and implement a general model for communication protocols based on the principles of finite state machines and make the design of transport entity more modular and easier to maintain and modify. We have designed an inference method and knowledge representation, based on semantic networks, for implementing this model. We have added interactive capability and automatic error detection to check for invalid external events and other types of errors in our model. PFSM consists of one or more knowledge bases depicting the state machine model for each communication protocol, an inference engine that uses the knowledge base(s), a working memory, a knowledge acquisition subsystem to gather the data required to build the knowledge base(s), a dialog subsystem to conduct an interactive conversation with the user(s), and an explanation subsystem to explain the inferencing mechanism. (Abstract shortened with permission of author.)

The growing widespread use of data communication networks has led to increased reliance on the availability of network resources. The network itself is a critical resource which must be managed in a timely and effective manner. In order to manage the network effectively, the network manager must have powerful tools that present network information in a fast and logical way. The work presented here is the design and development of a network management tool for Sytek broadband networks. The Sytek Network Management Package (SNMP) incorporates a commercial database management system, Rbase System V, and menu oriented management functions for the University of Arizona Sytek broadband networks. The SNMP is written in C and executes on a PC connected to the Sytek network. The SNMP allows a network manager to manage both the Sytek LocalNet 20 and System 2000 networks.

Presented in this thesis is the Airborne Countermeasures Ejection and/or Release (ALE)-XX Cockpit Control Unit (CCU) Countermeasures Dispensing System Network Controller (CMDSNC) design. ALE-XX CCU CMDSNC was designed as part of the total ALE-XX system to replace the problematic ALE-40. Fiber optic technology is incorporated into ALE-XX as the communication medium to eliminate Electromagnetic Interference (EMI). ALE-XX CMDSNC uses a star network to solve system operation failures from the existing daisy-chain topology. A comprehensive Built-In-Test (BIT) allows fault diagnose and isolation of hardware problems reported on the CCU Visual Display. Digital electronics replace the electro-mechanical devices, lowers the number of Line Replaceable Units (LRUs), and raises the Mean-Time-Between-Failures (MTBF). The information contained herein could be used as a design aid for future CMDSNCs or other related instrumentation.

No description available.

For the past few years, the University of Natal has been using an HTML-driven InnerWeb as its intranet system. The advantages of database driven intranet technologies over static HTML pages are now well established. It was felt that the University should change to a database driven intranet system which would better serve the needs of the University community. The first part of this study was conducted to establish user perceptions and requirements of such an intranet. Results from this study suggested that the functionalities and needs expressed by participants are synonymous with functionalities offered by database driven intranets. The second part of this study was therefore to follow up and prioritise the identified requirements for the main intranet interface to establish a controlled vocabulary and investigate current debate on the possibilities and limitations of intranets as a knowledge management tool. Part of the study took cognisance of Stoke's use inspired research premise by adapting constructivist research philosophy as well as Van den Akker's development research strategy to guide the study. Eclectic mixed methodology as suggested by Reeves guided the research design for this study. Thus data gathering methods which included group and on-line card sorting, semi-structured interviews, category membership expectation tests and prototype validation were used to validate each stage of the development process. Data analysis procedures included using Microsoft Excel to calculate the total score assigned to each item for possible inclusion on the intranet, cluster analysis using IBM EZSort software, analysing interview transcripts using QSR NVlvo software as well as simple eye balling of the category membership expectation data. The initial 93 items for possible inclusion, which were identified at the first part of the study were reduced to 60 items. Some distinct themes, which were identified, include research activities, library, social notices, corporate notices, learning activities, University Policies and Procedures, student activities, staff activities and on-line collaboration . The results of this study suggest that it is challenging to establish vocabulary which is common to the majority of prospective users. Thus, some of the suggested vocabulary for category labels did not have majority consensus. This study also suggests that participants expect a process driven intranet, which offers multidimensional access points and multiple ways to navigate. This implies analysing same data from different viewpoints. Participants want more from an intranet than simple document publishing though a few can not see the intranet beyond a document retrieval tool. The study suggests that users have different needs which could be better addressed by offering customisation and personalisation functionalities to suit users' individual needs. Participants expect to use the intranet as a reliable institutional memory which offers seamless remote access to synchronous and asynchronous communicating tools, access to various forms of digital media, interactive on-line administration functionalities as well as access to on-line academic related activities. / Thesis (M.A.)-University of Natal, Durban, 2003.

Many of the contemporary routing algorithms use simple mechanisms such as flooding or broadcasting to disseminate the routing information available to them. Such routing algorithms cause significant network resource overhead due to the large number of messages generated at each host/router throughout the route update process. Many of these messages are wasteful since they do not contribute to the route discovery process. Reducing the resource overhead may allow for several algorithms to be deployed in a wide range of networks (wireless and ad-hoc) which require a simple routing protocol due to limited availability of resources (memory and bandwidth). Motivated by the need to reduce the resource overhead associated with routing algorithms a new implementation of distance vector routing algorithm using an agent-based paradigm known as Agent-based Distance Vector Routing (ADVR) has been proposed. In ADVR, the ability of route discovery and message passing shifts from the nodes to individual agents that traverse the network, co-ordinate with each other and successively update the routing tables of the nodes they visit.

Approved for public release; distribution is unlimited / The advent of Wireless Local Area Networking (WLAN) has seen a widespread adoption of its technology and functionality in many different areas. Many studies show more and more organizations are extending their networks to incorporate wireless devices and their applications. Permitting wireless devices to access private networks however, further complicates the tasks of protecting the network and its resources from unauthorized access. Now that they have become a significant element in today's networks, selecting and deploying adequate security measures have become the focus of many research efforts. Typically, network managers implement countermeasures to augment security. The goal of this thesis is to research approaches that compliment existing security measures with fine grain access control measures. The Extensible Markup Language (XML) is adopted to accommodate such granular access control as it provides the mechanisms for scaling security down to the document content level. / Captain, United States Marine Corps

Approved for public release; distribution is unlimited / In order to ensure the confidentially, integrity, and availability of networked resources operating on the Global Information Grid, the Department of Defense has incorporated a "Defense-in-Depth" posture. This posture includes the use of network security mechanisms and does not rely on a single defense for protection. Firewalls, Intrusion Detection Systems (IDS's), Anti-Virus (AV) software, and routers are such tools used. In recent years, computer security discussion groups have included IDS's as one of their most relevant issues. These systems help identify intruders that exploit vulnerabilities associated with operating systems, application software, and computing hardware. When IDS's are utilized on a host computer or network, there are two primary approaches to detecting and / or preventing attacks. Traditional IDS's, like most AV software, rely on known "signatures" to detect attacks. This thesis will focus on the secondary approach: Anomaly or "behavioral based" IDS's look for abnormal patterns of activity on a network to identify suspicious behavior. / Major, United States Marine Corps