Linux-based network test system design (1)

Introduction to Linux is the last couple of years by people more concerned about a new thing.

It from a college course design has become a powerful operating system, people are on it. Computer industry faster and faster, now is toward the development of high-speed network. Linux as a product of the Internet, but also represents the historical trend. On Linux for study, research and application development is imperative. Linux not only represents an operating system, but rather represents a powerful and effective integration of the system. In the above, we can not only be engaged in the study of the operating system, and can be applied to network; and because it also comes with a number of free development system, develop your own applications is also very convenient and efficient. All of this so that I chose Linux and earlier into the application and development of Linux. This experimental system is Linux-based network experiment system. In this experiment design, because the system is to use Linux, so some configuration comparison cumbersome (in NT on just a few mouse clicks you will be able to resolve things is no exception). But is this a text configuration files, some server settings in principle have a lower level of comprehension (on NT on why you want to do some further understanding); at the same time as the Linux program for batch ability is strong, it is also very strong development of the language, resulting in the development of the experimental procedure relatively easy for many (this reflects the powerful features of Linux), and some NT on comparison difficult but in Linux is very good. This experimental system actually design a small Intranet, in the above you can simulate the Intenet's operations, but can also be true of the Internet for operation. At the same time, since it on Linux, on later opened other related networks, operating systems, software engineering, database development, experimentation is very useful. The first chapter of the experimental design overall awareness and section 1 Introduction to Linux Linux is a Unix operating system class, which is managed by Helsinki University students create LinusTorvalds in 1991 and unselfish in Internet publishing, anyone to comply with the GPL copyright, can be free to use and modify the Linux. In fact, the GPL requires a full share of the software, you can profit from it, but you can't for itself. Through the Internet and thousands of volunteers to continuously modify, eight years later, Linux has become incomparable!, especially since the second half of last year, IBM, Intel, Oracle, Sysbase, Borland, HP, SUN, Corel, and other commercial software manufacturers have expressed on Linux for business development and technical support, and more make Linux more and more high commercial value. At the same time starting this year, Linux will develop in two directions, namely micro devices embedded operating system and desktop operating systems. IDC forecasts in 2003, Linux will become a WindowsNT's second largest after the operating system. Domestic companies (Hwa sheng, soft, stone, etc.) are also engaged in the expansion of the Chinese Linux and application development, they also feel domestic Linux education of necessity and urgency, the urgent need for a large number of Chinese Linux developers. As an operating system, Linux has the following advantages: 1, it has all the features of Unix, Unix-rich software resources and C language platform portability makes it a very rich on the software. Also, due to the popularity of Linux, other UNIX platforms Porting Linux applications. 2. Linux built-in network support, the application of the standard TCP/IP Protocol, Ethernet network connection or through a Modem himself and other systems, you can access the Internet. The network performance is extremely good, according to statistics United States 130 million web sites, more than half are running Apache on a Linux system. 3, it has the perfect multitasking, can simultaneously run multiple tasks, and access to multiple devices. 4, Linux has superior memory mechanisms: in only 32 megabytes of P133, driving tens of workstations connected to the Internet, you almost feel hard drive swap activity. On the workstation user to run, the feel and the same dedicated server and even faster than a dedicated server. 5, standard with IEEEPOSIX.1 compatible. 6, GNU software support: Linux can run a wide range of the GNU project of the free available software. 7. software version update speed is very fast, and every few days and you can see the new kernel version. 8, good performance, the biggest advantage of Linux is its source code is open and free characteristics, with extremely low cost anyone can access it and modify it freely. 9, on domestic users, Linux application software on the Chinese also abound, at the same time we also saw Linux Chinese version (XteamLinux and TurboLinux Chinese version). 10, on the user, the Linux rich networking support and ease of development, applied to network teaching good prerequisite conditions and high performance-price ratio. Visible for Linux research and applications, and apply to teaching, and learning have very good help at other courses and research work is also a great role. The second section of this topic in Linux's role in this topic, I put the Linux as experimental server software use. Was not on the client or use Linux, on the one hand, to consider Linux in application software flaws (not do not have the appropriate software, simply because the operation is complicated, the interface is also unfriendly), aAlso considering the laboratory conditions and experiments for ease of manageability. The following is the subject of an overall framework diagram: shows: in the experimental system after considerable awareness, combined with TCP/IP and knowledge of Linux system design and implementation. System settings for your network services to enable them to better provide experimental service. On the control, the corresponding procedure is complete. Students on the machine, you must apply through the account application process, and to experiment account fill in the necessary information for students; experiment management teacher through program review system users. Each time a student experiment is completed, the management of the teacher to remove over management program and its experimental data, the user account to the next experiment. Section III of experimental system for the overall planning of experiment system uses a Client/Server model design, fully embodies the Linux network features and highlights the nature of the experiment. All of the services that are running on a Linux server, the client program are based on the interface better Windwos system. The client through the client to use TCP/IP protocols and server communication. It can be said that the entire system is a model of the Internet. Experimental system diagram shown in Figure 1: main technical description: the entire system does not have any changes to the hardware system, only the requirements on the client computer to the appropriate setting changes. Experiment all the server-side software is running on Linux. Linux server to provide DNS service, every computer the DNS to point to the Linux server. Client TCP/IP related protocols and server communication, client to install the appropriate software for experiment. Client program for the interface better Windows programs that benefit the experimenter to experiment. Figure 1 [TheNo.1Picture.]] Experimenter must pass an experiment account, make the necessary registration information input to perform experiments. This function through CGI implementation on the Web, while the procedures to the appropriate user information saved in the file; by another CGI, an administrator can get the experimental user information. Experiment management implementation by a management script, main features are: remove the user's data, clear some log files, clear the cache of some server software. Each user is only a certain amount of disk space, more than a certain number, the system will reject the user for data upload, delete some user data.