The concept of forward proxy
Forward proxy, also known as the legendary proxy, works like a springboard.
Simply put,
I am a user and I cannot access a certain website, but I can access a proxy server
. This proxy server, he can access it. The website that I can't access
So I connect to the proxy server first, tell him I need the content of the website that I can't access, the
proxy server goes and retrieves it, and then returns it to me
From the website's point of view, there is only one record when the proxy server fetches the content.
Sometimes it is not known that it is the user's request, and the user's information is also hidden. It depends on whether the proxy tells the website or not.
The conclusion is that a forward proxy is a server between a client and an origin server. In order to get content from the origin server, the client sends a request to the proxy and specifies the target (the origin server), and then the proxy forwards to the origin server. Request and return the obtained content to the client. Clients must do some special setup to use forward proxy.
The concept of reverse proxy
Continue the example: For
example, a user visits http://ooxx.me/readme
but there is no readme page on ooxx.me.
He secretly retrieves it from another server and spit it out to the user as his own content
But the user doesn't know
it's normal, users are generally stupid
The server corresponding to the domain name ooxx.me mentioned here has a reverse proxy function set
The conclusion is that a reverse proxy is just the opposite, it acts like an origin server to the client, and the client doesn't need to do any special setup. The client sends a normal request to the content in the reverse proxy's namespace (name-space), and then the reverse proxy will determine where (original server) to forward the request and return the obtained content to the client, like these The content was originally its own.
Difference between the two
In terms of usage :
A typical use of forward proxies is to provide access to the Internet for LAN clients inside a firewall. Forward proxies can also use the buffering feature to reduce network usage. A typical use of a reverse proxy is to make a server behind a firewall accessible to Internet users. A reverse proxy can also provide load balancing for multiple servers on the backend, or provide buffering services for slower servers on the backend.
In addition, the reverse proxy can also enable advanced URL policy and management technology, so that web pages in different web server systems exist in the same URL space at the same time.
In terms of security :
A forward proxy allows clients to access arbitrary websites through it and hides the client itself, so you must take security measures to ensure that only authorized clients are served.
The reverse proxy is transparent to the outside world, and the visitor does not know that he is accessing a proxy.