Application of cross-platform interoperability tools

(Author: Xue qikang)

For Windows, Linux, and UNIX, real masters need to "break them all over the internet". As you move toward Masters, it is necessary to master the interoperability between heterogeneous operating systems. This article will reveal the secrets of such tools.

VNC: Transfers mouse and keyboard movements to allow you to remotely control computer hosts of different operating systems;

X manager -- enables you to run Unix applications in windows;

Cygwin is a powerful Unix simulation tool in windows. It also helps you learn UNIX in windows.

With the rapid development of the network, the architecture originally dominated by Windows has begun to change. In particular, the rapid development of Linux provides more options for daily applications. However, operations vary greatly among various operating systems. Computer Professionals are facing a more complex situation-there are many computers in the company, and the operating systems running on them may be Linux, Solaris, And FreeBSD, it may also be HP-UX, Aix, or other UNIX systems, but more systems may be Windows systems.

When managing different computers, administrators always need to operate on the console of that computer. If the company is distributed in different floors of a building, it is too troublesome for managers to run around. Moreover, if their computers are hosted in the Telecommunications Board, the company's network management system may not often run a long way to host the data center for maintenance.

In view of this, I recommend the interoperability software between several heterogeneous operating systems. Take Windows 9x/NT/2000 as an example. Generally, this type of software can be divided into two types: console-based simulation, that is, in a Windows environment, simulate a remote console, as a remote terminal, log on to the remote UNIX system through the network; another is the simulation based on X Window, which runs an X Server locally, run x applications on a remote unix host.

Remote logon Tool
Either way, it is necessary to use the network based on the TCP/IP protocol. The network can be a LAN in the company, a WAN connected to each other through a leased line, or the Internet.

For UNIX systems, terminal simulation tools are usually used for remote management. Common tools include Netterm. The current version is 4.2; CRT; the current version is 3.1.1. Of course, there are also many excellent terminal simulation software that can run well in Windows systems. However, I prefer CRT, which is a very good terminal simulation software. In Windows 800x600, the display mode is 1024x768, greatly increasing the terminal display size. Because CRT can provide a much larger display area than other simulation terminal software, more information can be displayed on the same screen, as if the screen is much larger. Another advantage of CRT is that it does not have to log on again like NetTerm. Other software can be found at the address below: http://winfiles.cnet.com/apps/98/terminals.html

A large number of terminal simulation software are collected here. You can try it and use one that you think is satisfactory.

X Server in Windows
In the past, ordinary users did not know much about UNIX, so they did not care whether the GUI can be used in UNIX. There are still many people who don't even know that the GUI can be used in UNIX. Now, with the continuous development of Linux, it is gradually accepted by the majority of common users. In Linux, there is a very useful X Window, which is also a GUI that looks no different from Windows.

X Window looks like Microsoft's Windows, but its mechanism is completely different from Microsoft's Windows. First, it is a standard C/S system, that is, to complete a task, X customer and X Server negotiate together. X client can be an application on the local machine or an application on the remote host. In addition, it also has a desktop management tool called Window Manager, which is responsible for window creation, deletion, and other basic operations. Window Manager includes KDE, GNOME, and TWM.

If you want to run Unix applications in Windows, you need to find an X server that can run in windows. If you have a server that can run in windows, X applications in other UNIX systems can be run locally. Generally, some commercial X servers are used, which are generally expensive. If you want to use such software, I recommend x manager, which is an excellent X Server (for Windows 9x/NT/2000 ).

Such software includes image X Server and X-omin, which can be downloaded at http://winfiles.cnet.com/#/98/terminals.html.

In the free GNU project, there is a personal X Server for Windows software package, which is ported from x11r6 to cygwin. Related software can be found under the http://www.cygwin.com.

Virtual Network Computing
This type of software is represented by VNC under the GNU project. It is a comprehensive software that operates on different operating systems in multiple ways. It is implemented through remote control, that is, through the interaction between the VNC server installed on the remote host and the client program installed locally. The implementation process is as follows: after the client successfully connects to the server, the client negotiates with the server to transmit the screen information of the remote host to the local device, send the local keyboard and mouse movements to the server through the client program, and then the server operates according to the corresponding instructions, and the results are returned to the server. In this regard, it is a bit like pcAnywhere. In addition, VNC provides a function to control remote hosts through a browser. Users can directly operate remote hosts through a browser.

VNC consists of VNC servers and VNC viewers. It supports the following environments:

VNC Server: VNC Server for X (UNIX), WinVNC (VNC Server for Windows), and macvnc (VNC Server for PPC Macintosh ).

VNC viewers: VNCviewer for X, VNCviewer for Windows, VNCviewer for Java, VNCviewer for Macintosh, and VNCviewer for Windows CE.

VNC is a mature application that runs on popular operating systems and is easy to install and use. If you want to use VNC, you can download it at http://www.uk.research.att.com/vnc.

Based on security concerns, VNC can also run well under SSH. For detailed installation steps, see the following webpage: http://www.uk.research.att.com/vnc/sshvnc.html. I have explained how to use vncthrough ssh.

Network security tools
With the development of the network, network security has been mentioned as a very important position. Because traditional telnet and ftp are used, users' passwords are directly transmitted over the network without any encryption. If someone runs something like sniffer on the network, the user's password and data can be obtained by them. This requires us to use a safer remote logon system.

Currently available secure remote login software has SSH, where SSH1 is a free software package named SSH-1.2.27. SSH @ SSH2 is compatible with SSH1. However, it is a commercial product and requires a certain fee. SSH uses an encryption mechanism to remotely transmit passwords and data, which prevents malicious users from obtaining user passwords and data.

SSH software packages are divided into servers and clients. Most of the servers are UNIX software packages. GNU has transplanted version 1 to the NT environment. The client can be UNIX or Windows. The following describes several SSH-based remote terminal software packages and some FTP software packages that can be run based on SSH.

SSH1 software package can be searched in any search engine (type SSH1 ). The SSH2 package can be downloaded directly from www.ssh.com. For non-commercial users, individual users can download the package. . If you want to install the client in Windows, you only need to download ssh2win_2.40.exe. In addition to the secure remote login package, this package also provides secure file transfer. For the installation method, refer to the installation instructions in the software package. The installation process is as long as the installation instructions are followed, and there are usually no problems.

With this tool, network administrators do not have to worry about theft of user names and passwords during remote system maintenance. Other similar tools include secrurecrt (Remote Terminal simulation that supports SSH), securefx (file transfer tool that supports SSH), and http://www.vandyke.com/download/index.html.

Other similar software: http://winfiles.cnet.com/#/98/terminals.html.

Summary
If you use Telnet to remotely log on to and manage internal servers on the company's internal Lan, you can choose netterm, CRT or even the self-contained Telnet tool in windows; if you often use Windows to log on to the company's internal server using UNIX, I suggest you download the CRT. After using it, you will find that this is indeed good.

If you prefer X Window's gorgeous Window Manager, we suggest you choose x manager, which is the best X Server for windows I have ever seen. Running it in windows and connecting to CDE using the Sun system can certainly cheat many people who think that you are using a high-end iSCSI workstation (if there is a good monitor ). I have used other X Server for windows, all of which have their own characteristics. However, it is best to use X manager.

If your company is using multiple operating systems, you 'd better choose VNC, which provides the best support for heterogeneous operating systems. In addition, administrators can choose multiple management methods, which can be remote control or browser control. The VNC software package is relatively small and easy to install. It is suitable for internal use within the company without too many configurations. VNC has poor security and is generally suitable for short-term configuration of remote hosts (on the public network). It is best to stop the service immediately after the configuration is complete.

SSH is the most secure, and it is developed specifically for the security of remote servers. With it, all the communication data between the server and the client is encrypted, and all the data obtained by the Network listener is encrypted, so the real data cannot be obtained. In addition, SSH allows communication between specified hosts. Other hosts not registered in the system cannot connect to the server. SSH provides a large number of tools to make it easy for remote users to use the system. Users can also use third-party software that supports SSH2.

By adding appropriate parameters during SSH2 compilation, you can also run remote X applications on SSH2. Basically, SSH has become an essential tool for secure communication between remote systems. However, there are advantages and disadvantages. Because SSH communication uses data encryption and decryption technology, transmission efficiency is inevitably reduced. After all, encryption and decryption takes time! In addition, SSH configuration is difficult for general users. However, it can improve the security of the system, so it is worthwhile to spend more time getting familiar with its configuration.

Source: CCID