Basic Knowledge: A detailed description of Layer 7 Exchange

In terms of high availability and load balancing, there are many advanced tools that can use the Layer 7 Information returned by the application to the end user. The user can not only verify whether the correct content is sent, but also enable the packets transmitted over the network without considering the IP address or port), and make a load balancing decision based on the information in the package.

In essence, this smart migration surpasses the fourth layer of functionality. Devices with a maximum of layer-4 functionality cannot identify different types of transmission streams flowing through this port, so they treat all transmission streams equally.

However, the transmission streams are not all the same. For Server Load balancer products, it is useful to know whether the data flowing through this port is streaming media or simple requests for a commodity in the product catalog, maybe the merchant wants to give the customer who needs this directory item a higher priority. Many devices with layer-4 functions treat these two types of data in the same way, so they may send streaming media data to servers that cannot respond, resulting in incorrect information and latency.

The intelligence on the seventh layer can further control all transmission streams and content. Some of these features of a layer-7 cognitive product ensure that different types of transmission streams can be given different priorities. Devices with layer-7 cognition do not rely on routing devices or applications to identify the Diff-Serv), general open policy services, or transmission streams of other service quality protocols, it can filter transmission streams and assign priority values. Therefore, you do not have to rely on applications or network devices to achieve these goals. Layer-7 switching can achieve effective data flow optimization and intelligent load balancing.

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