The Design And Implementation Of Emulational Education System For Network Protocols

With the advent of the information age, the network economy is increasingly affecting all aspects of the entire community, the network has with the growing influence of the network in depth, the people whether in our society will also have a basic knowledge of network and operating capacity as a measure of a qualified university student standard. In this application needs, one after another the major colleges and universities introduce network courses into the important curriculum all over the country, so network principle of education to embark on the universal road.Network theory is an important segment in computer teaching system. However, because of too abstract, it is difficult to understand the real principle of the network after ending the study, up to the required teaching results. In addition, stressed the importance of the principle, network theory also more highlights practical operational capacity, students only through the theory and practice of the training mode, which can truly appreciate the wonders of the Internet. At present, however, many colleges and universities are widespread the phenomenon of "Heavy theory, light practice", the causes is not the school does not consciousness, but a lack of a sound, the standard experimental environment and appropriate teaching tools. How to establish a set of standards based on international protocol network experiment is the key for many colleges and universities to further deepen network education.Emulational education system for network protocols ( advanced edition ) for the relevant professional colleges and universities teach computer networks, in particular the TCP / IP protocol family, provides a visualization of the practical teaching platform. Through the various data visualization frame editing, simulation sent, and capture analysis and conversation, the students can understand and master the internal principles of network protocol and operating mechanisms; Through the use of self function-defined protocol, the students can compile the protocol by their hands, such as syntax, semantics, timing of all elements, and then tends to have a deep understanding design and implementation of the protocol. In addition, the system also provides network programming, network attack and defense as well as network efficiency analysis, and other related courses. The contents of experimental courses focus on the students'hands-on designs and analytical capabilities and strive to cultivate innovative talents.The system has the following features:1. Integrated hardware designSystem hardware designed independently by the Company, with the highest performance of hardware, which increases flexibility and scalability of system2. The standardization of software designsoftware engineering system Follows software design thinking, focuses on humanity and ease of use3. Efficient analytic speedUsing zero-copy data technology, to improve the system of analytic speed, fully meets the needs of experiment4. Flexible expansionBy using the protocol script, the system can be easily expanded to an protocol, based on the cluster model experiments, the system size can be carried out under laboratory expansion 5. Easy Installation and MaintenanceServer operating system adopts the way of Linux, with the automation of the installation process, script of application service configuration, and provides the operating system recovery tools6. Unique Capture TechnologyData Acquisition concurrently supports to multiple NICs and even can be combined with data comparison7. Abundant contents of experiments (including 35 experiments, 83 exercises)Covers TCP / IP protocol family, and plans a number of designs and innovative experiments8. Intelligent Network Topology Verification TechnologyAccording to the contents of different experiments use different network structures, the system provides network connectivity testing tools, which all can simplify test preparations9. The Chinese-English bilingual interfaceThe system provides Chinese and English interface and the two protocol script, suitable for Bilingual Education10. Vivid interface11. aesthetic and generous interface, and provides vivid protocol hierarchical model pictures and intuitive pictures conversational interaction pictures to facilitate students understand every layer's protocol.The software composition of this system major contains protocol editor, protocol analyzer, as well as tools kit.In these software, in order to improve efficiency, we used C++ as basic develop language, meanwhile, used C language manipulate bottom level driver program directly. Interface part, it designed according to Windows operating system to pursue very good usability.Protocol editor use various data source, so it can be compatible with other software such as sniffer. To dozens of network protocol which experiment involved, determine every protocol's fields definition, display mode, as well as suggest information. User can edit quickly and conveniently. More over, it can fill associated fields automatically, and check legitimacy of these fields. At the same time, it sends sequence of edited frame to network simulately, and set sending interval and sending times. Additional, it also provides auxiliary function such as address book and checksum calculator.For handle each type of protocol flexibly, protocol editor using XML-based general Protocol Description Language (PDL) to describe each type of protocol. When the software need to add a new protocol, it only need to add corresponding PDL to protocol description script, and no need to change program.Protocol analyzer base on NDIS driver, it can capture network data real-timely and statistical analysis. Analyzer can capture data stream which bypass through receiver's NIC, it can't send data packets itself, so that it don't affect network. Analyzer provides hundreds of protocol analysis functions, and can capture data according to filter condition which user selected, also can store captured data frames on disk, for analysis or edit later. It also provides address book, traffic statistics, protocol distribution, and other functions.Both protocol editor or analyzer can display data frame's all protocol level in tree form, list value, content and detail explanation of each fields, meanwhile display corresponding Hex or ASCII code. To enable students understanding to specific content and internal relation of protocol, so as to improve the understanding to the network.The system is advanced experimental teaching tools as a domestic auxiliary teaching initially for "computer network", supports multiple network topologies, supports multiple protocol analysis and simulations .The Ministry of Education has adopted a system of scientific and technological achievements, the project is a cooperatively research project of CSS&JLU INFO-TECH CO.,LTD. and the computer institute of Jilin University. Products have already used nearly 100 colleges and universities and received unanimous praise in the country.