Proxies

It is an intermediate server between the client and the back-end server
Clients connect to proxy servers to request for a service like a web page, file, connection, etc.
In short, a proxy server is a piece of software or hardware
- that acts as an intermediary for requests from clients seeking resources from other servers.
Typically, proxies are used to filter requests, log requests, or sometimes transform requests
- e.g. (by adding/removing headers, encrypting/decrypting, or compressing a resource)
Another advantage of proxy server
- its cache can serve a lot of requests
If multiple clients access a particular resource
- the proxy server can cache it and serve it to all the clients without going to the remote server.

Proxy Server Types

Proxies can reside on the client’s local server or anywhere between the client and the remote servers
A few types of proxy servers:

It is a proxy server that is accessible by any Internet user
Generally, a proxy server only allows users within a network group (i.e. a closed proxy)
- to store and forward Internet services such as DNS or web pages
  - to reduce and control the bandwidth used by the group
With an open proxy, however, any user on the Internet is able to use this forwarding service
2 famous open proxy types:
1. Anonymous Proxy
  - reveаls іts іdentіty аs а server but does not dіsclose the іnіtіаl IP аddress
  - Though thіs proxy server cаn be dіscovered eаsіly
    - іt cаn be benefіcіаl for some users аs іt hіdes their IP аddress
2. Trаnspаrent Proxy
  - Thіs proxy server аgаіn іdentіfіes іtself, аnd wіth the support of HTTP heаders, the fіrst IP аddress cаn be vіewed
    - The mаіn benefіt of usіng thіs sort of server іs іts аbіlіty to cаche the websіtes

It retrieves resources on behalf of a client from one or more servers
- These resources are then returned to the client, appearing as if they originated from the proxy server itself