Fast understanding of forward proxy and reverse proxy

Forward agency （Forward Proxy）

Forward proxy refers to the use of a proxy server to access the target server
The proxy server is user oriented

Common scenarios

1. To speed up access
   Like a game accelerator , Various agent software , Is to use the principle of forward proxy . For example, to access GitHub, The original network access speed will be relatively slow , The purpose of acceleration can be achieved through foreign proxy servers .

2. Agent access
   Software development , Some services are connected , The service is set to ip White list , Only through specific ip Go to the service , At this time, you can request locally through proxy , Easy to develop and test .

Reverse proxy

The agent is a forward user , The reverse proxy is the opposite , The proxy object is Target server , It refers to that the server uses the proxy server to provide services to users .
Compared with forward agent , Both are implemented by proxy server , But the subject of the reverse proxy is the server , Therefore, reverse proxy is transparent to users , In the user's view , The proxy server is the target server .

Reverse proxy is configured for back-end services in enterprise applications , For example, common nginx , also LVS/F5 etc. .

summary

The forward proxy needs to be configured by the client , Generally speaking, we will configure through the tools or interfaces provided by the browser or operating system . This is the time , The proxy is not transparent to the client , The client needs to know the address of the proxy and configure it manually . Configured the agent , The browser will make special modifications to the message when sending the request .
Reverse proxy is transparent to clients , In other words, the client generally does not know the existence of the proxy , Think you are communicating directly with the server . Most of the websites we visit are reverse proxy servers , The reverse proxy server will forward it to the real server , Generally, the reverse proxy layer is used to realize load balancing and high availability . And you can see it here , The client will not know the real server ip Address and port , This has played a role of security protection to a certain extent