Mentioned remote management, usually refers to the remote management server, rather than a personal computer. Personal computer can be used to use at any time, servers are typically placed in the engine room, the user can not directly access to the server hardware, but to use remote management approach.
Remote management, in fact, between the computer (server) via a network data transmission process (exchange of information), the browser needs to HTTP protocol as (Hypertext Transfer Protocol) web browsing, remote management also needs to support remote management protocol.
At present, the commonly used remote management protocol following four:
- RDP (remote desktop protocol) protocol: Remote Desktop Protocol, most Windows systems that support this protocol by default, Windows Remote Desktop management system based on the agreement.
- RFB (Remote FrameBuffer) protocol: graphical remote management protocol, VNC remote management tools based on this agreement.
- Telnet: command line interface to remote management protocol, almost all operating systems support this protocol by default. Characteristics of this protocol is transmitted in the clear using during data transmission, i.e. data is not encrypted.
- SSH (Secure Shell) protocol: a command line interface for remote management protocol, almost all operating systems support this protocol by default. Telnet and different from the data transmission protocol will encrypt and compress the data, using this protocol for transferring data both safe and fast speed.
RDP contrast RFB
RFB protocol RDP protocol and allow users to access the remote system through a graphical user interface, but the transmission image tends RFB protocol, the RDP protocol tends to transfer instructions:
- RFB protocol will draw a good server-side window in the memory, and then the image to the client, the client only need to decode the image display can be obtained;
- Paint RDP will work to the client, the server needs to make the appropriate adjustments based on the display capabilities of the client.
Thus, the same operation is completed, the amount of data transmission than the RFB protocol RDP large, and the RDP client is more demanding than the RFB, RFB applied to a thin client, RDP applied to the low-speed network.
Thin client is relative to the fat client in terms of, for instance, people use QQ, you need to download the client, which is a "fat client"; on the contrary, it is possible to view a variety of information on the Web through the browser without having to download anything else software, which is a "thin client." Simple to understand, thin client refers to the maximum extent possible to reduce the burden on the client, most of the work is done by the server; thick client and vice versa.
Telnet SSH contrast
Telnet protocol and SSH protocol are command-line remote management protocol, common applications, commonly used in remote access server.
Compared Telnet protocol, SSH protocol data will be encrypted when transmitting data operation, data transmission is more secure, and therefore the SSH protocol Telnet protocol in place almost all applications.
In some tests, no encryption occasions (such as local area network), Telnet protocol is still often used.
Linux Remote Management Software
Based on the above four kinds of remote management protocol, Linux server remote management software can be divided into the following three:
- VNC similar graphical remote management software (based on RFB protocol), such as Xmanager, VNC VIEWER TightVNC and the like;
- SSH protocol based on a command line operations management;
- Webmin similar browser-based remote management, this management approach provides only a simple window management, limited availability of management;
Consider the range of security and stability, most of the servers are discarded graphical management interface and select a command-line interface, so often used to remotely manage Linux server command line management based on SSH protocol.
Currently, based on SSH protocol commonly used remote management tools PuTTY, SecureCRT, WinSCP, etc. These management tools specific use in the next section to find out more.
