Now most of the operating systems of network devices support NTP communication protocols, such as Unix and Windows, which have their own NTP service functions. For example, NTP in Windows. As each system manufacturer will optimize and set up NTP according to its own system, it is more suitable for his own system, and compatibility with other systems will be much worse. There are also different versions of NTP services that will be used in different periods.Because each version requires some of its own characteristics. So there are some compatibility problems when setting up the NTP server. Therefore, in the environment of many types of operating systems, try to use the software provided by NTP official organizations to set up without using other vendors' default NTP servers in the system.

Operation mode of NTP server

The usage of NTP server includes fixed connection and dynamic connection. In fixed connection, the client only receives the specified server side connection, and no matter whether the server is connected normally, he will not change the other server's receiving time. The general client / server mode is this mode. In addition, the client always receives the broadcast information on the server side, and when a server stops service, the client can update the time normally as long as the server has broadcast the correct and reliable time information. It is usually connected by broadcast mode.

The client server mode is the most widely used method on the Internet. After setting up the server, he can flexibly configure the client to let the client choose whether to use the NTP server or to use the NTP server. The client server uses the commonly used RPC mode to transmit time information. They run in a way that the client sends time to the server side, and then adjusts the time according to the reply from the server side.

In general, the client can define the interval between their synchronization time and request the maximum and minimum time interval. The client will compare according to their clock time and NTP server time. If the client's local clock is more accurate, the interval between them will be longer. If the error of the local time is large, the client will make a time request in a relatively short time to ensure the accuracy of the client time.

NTP is a protocol for synchronizing the computer clock on a network computer. It uses the adjusted Greenwich time (UTC) to synchronize the time of the computer to exactly milliseconds. Of course, in order to prevent malicious attacks against the time server, the NTP protocol uses the identification mechanism to check whether the time information is really from the claimed server and checks the return path of the information, and provides protection mechanisms against interference.

Under the basic conditions, the NTP client sends out the time request and exchanges time with the time server.Usually, there are 6 exchanges every 5 minutes to 10 minutes at the initial stage of the setup. Once synchronized, every ten minutes will synchronize with server time, usually requiring a single exchange of information.

NTP server working mode

NTP's work mode: Master / passive symmetric mode:
One to one link can synchronize the other side or be synchronized by the other party. The first party to issue an application is to establish a connection, and the other side to work passively.
In mode, this mode is suitable for configuring redundant time servers.

The client / server mode is basically the same as the main / passive mode. The only difference is that the client can be synchronized by the server side, but the server side can not be synchronized by the client.

Broadcast mode: it is a one to many link service. No matter what mode the customer works, the server sends out the time information voluntarily, and the customer receives the time to update the information, so they adjust their time voluntarily, but the network has a certain delay. Accuracy is achieved with a certain loss, but it can satisfy second level applications. The broadcast mode is simple, but its accuracy is not high.

In general, the SYN2136 NTP server is recommended for the highly cost-effective model of the NTP server in the market.

This time server is designed with modern high technology and no hard disk. It is not restricted by environmental conditions such as regional climate, high cost performance, simple operation and maintenance free. It is suitable for unattended operation. This product can provide precise standard time signal and time stamp service for computer network, computer application system, process control management system, electronic commerce system, online B2B system, database storage and maintenance, and hard disk recorder.

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