From diversity to convergence : British computer networks and the Internet, 1970-1995

The Internet's success in the 21st century has encouraged analysts to investigate the origin of this network. Much of this literature adopts a teleological approach. Works often begin by discussing the invention of packet switching, describe the design and development of the ARPANET, and then examine how this network evolved into the Internet. Although the ARPANET was a seminal computer network, these accounts usually only briefly consider the many other diverse networks that existed. In addition, apart from momentary asides to alternative internetworking solutions, such as the Open Systems Interconnection (OSI) seven-layer reference model, this literature concentrates exclusively on the ARPANET, the Internet, and the World Wide Web. While focusing on these subjects is important and therefore justified, it can leave the reader with the impression that the world of networking started with the ARPANET and ended with the Internet. This thesis is an attempt to help correct this misconception. This thesis analyses the evolution of British computer networks and the Internet between the years 1970 and 1995. After an introduction in Chapter 1, the thesis analyses several networks. In Chapters 2 and 3, the focus is on academic networks, especially JANET and SuperJANET. Attention moves to videotex networks in Chapter 4, specifically Prestel, and in Chapter 5, the dissertation examines electronic mail networks such as Telecom Gold and Cable & Wireless Easylink. Chapter 6 considers online services, including CompuServe, American Online, and the Microsoft Network, and the thesis ends with a conclusion in Chapter 7. All of the networks discussed used protocols that were incompatible with each other which limited the utility of the networks for their users. Although it was possible that OSI or another solution could have solved this problem, the Internet's protocols achieved this objective. This thesis shows how the networks converged around TCP/IP

Teaching Coloured Petri Nets - a Gentle Introduction to Formal Methods in a Distributed Systems Course

This paper is about the two compulsory project assignments set to the students in an undergraduate course on distributed systems. In the first assignment the students design and validate a non-trivial layered protocol by means of Coloured Petri Nets, and in the second they implement the designed protocol in an object-oriented language. From the two assignments the students experience that Coloured Petri Nets, as a formal method, are useful for designing and analysing distributed systems. In the course students are introduced to basic concepts and techniques for distributed systems, and it is explained that such systems are often too complex to manage without using formal methods. In this paper we also report on our experience with teaching the course and describe the didactic methods applied. Based on the obtained experience we conclude that the combination of distributed systems and Coloured Petri Nets is fruitful --- the two areas complement each other. Although our experiences origin in Coloured Petri Nets, we believe that many of our observations hold for other formal methods as well.Topics. Education issues related to nets; Coloured Petri Nets; distributed systems; experience with using nets,case studies; applications of nets to protocols

Modeling and engineering software systems using Petri networks

Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2007.Includes bibliographical references (p. 38).A model of software applications for business process management based on colored Petri Networks is proposed and the corresponding application development process is exposed. A language is proposed to specify the enabling rules of the transitions. An algorithm to solve the binding problem is proposed and detailed. These elements allow the developers to isolate themselves from the very complex details of business process orchestration, transaction management, multi-threading issues, and to concentrate on the implementation of the transitions themselves. As a proof of concept, a lightweight business process engine based on that model has been implemented as well as the associated development and code generation tools.by Michaël Visée.S.M

From diversity to convergence : British computer networks and the Internet, 1970-1995

The Internet's success in the 21st century has encouraged analysts to investigate the origin of this network. Much of this literature adopts a teleological approach. Works often begin by discussing the invention of packet switching, describe the design and development of the ARPANET, and then examine how this network evolved into the Internet. Although the ARPANET was a seminal computer network, these accounts usually only briefly consider the many other diverse networks that existed. In addition, apart from momentary asides to alternative internetworking solutions, such as the Open Systems Interconnection (OSI) seven-layer reference model, this literature concentrates exclusively on the ARPANET, the Internet, and the World Wide Web. While focusing on these subjects is important and therefore justified, it can leave the reader with the impression that the world of networking started with the ARPANET and ended with the Internet. This thesis is an attempt to help correct this misconception. This thesis analyses the evolution of British computer networks and the Internet between the years 1970 and 1995. After an introduction in Chapter 1, the thesis analyses several networks. In Chapters 2 and 3, the focus is on academic networks, especially JANET and SuperJANET. Attention moves to videotex networks in Chapter 4, specifically Prestel, and in Chapter 5, the dissertation examines electronic mail networks such as Telecom Gold and Cable & Wireless Easylink. Chapter 6 considers online services, including CompuServe, American Online, and the Microsoft Network, and the thesis ends with a conclusion in Chapter 7. All of the networks discussed used protocols that were incompatible with each other which limited the utility of the networks for their users. Although it was possible that OSI or another solution could have solved this problem, the Internet's protocols achieved this objective. This thesis shows how the networks converged around TCP/IP.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Some Notable Discoveries in Organosilicon Chemistry: Proceedings of the History and Retrospective Session of the 34th Organosilicon Symposium (2001)

The 34th Organosilicon Symposium at White Plains, NY, in 2001 featured a History and Retrospective Session, during which invited speakers from academic and industrial laboratories recounted the path to some significant 20th century discoveries in organosilicon chemistry. The Si=C Story: The Way it Happened, Adrian G. Brook (University of Toronto) The Discovery of Stable Disilenes and Silylenes, Robert West (University of Wisconsin) Yellow Fever: The Story Behind the Synthesis of Germasilenes, Kim M. Baines (University of Western Ontario) Direct Synthesis of Tris(dimethylamino)silane, William B. Herdle (OSi Specialties, formerly of Union Carbide Corporation) Discovery of Tin and Phosphorus Effects on the Direct Synthesis of Methylchlorosilanes, Larry H. Wood (Dow Corning Corporation) Discovery of Methylchlorosilylene (CH3SiCl) as a Key Intermediate in the Direct Synthesis of Dimethyldichlorosilane ((CH3)2SiCl2), Kenrick M. Lewis (OSi Specialties, formerly of Union Carbide Corporation) The First Platinum-Catalyzed Hydrosilylation With Supported Platinum Catalysts, George H. Wagner (Retired, formerly of Union Carbide Corporation) The Discovery of Silicone Surfactants for Polyurethane Foam, Bernard Kanner (Retired, formerly of Union Carbide Corporation) The Discovery of Silane Coupling Agents, Bernard Kanner (Retired, formerly of Union Carbide Corporation)https://ir.lib.uwo.ca/organosiliconproceedings/1006/thumbnail.jp