Functioning Of Proxy Server
A conventional proxy faces both sides as a communication partner. He is therefore deliberately addressed (addressed) by them.
Here, the client asks the proxy to take over the communication with the target system on behalf of him. So z. B. the web browser configured so that it does not send all requests directly to the destination, but formulated as a request to the proxy sends.
There is also the transparent proxy as a special network component that behaves transparently (almost invisibly) to one of the two sides.
This page directly addresses the target and not the proxy. An appropriately configured infrastructure of the network automatically sends the request in question via the proxy eludes, without the sender can notice or even influence.
For the other side, however, the proxy continues to represent the communication partner to be addressed, which is addressed on behalf of the actual communication partner. Thus, a proxy generally appears for at least one of the two sides as a supposed communication partner.
Layer a proxy as a separate network component is physically located between the source and destination system. Within an IP network, it makes a conversion of the IP address as soon as the packets pass through the network on their way to the destination proxy.
As a result, the true IP address of the actual communication partner can be concealed, and individual users of a network or even entire networks can be connected to one another even if they are incompatible in terms of addressing technology of the unblocked proxy.
The latter is made possible by a special port management that allows a proxy z. B. allows to connect a private (self-contained) network via a single official IP address to the Internet.
Since the target system does not see the client but only the proxy, possible attacks from there are directed to the predestined proxy and do not directly hit the client.
The local proxy, on the other hand, runs directly on the source or target system and is in the logical arrangement between the network service to be contacted and the requesting client. It is mostly used as a filter or converter.
Since it goes into action on site, even before the packets are routed to the network (local proxy on the source system), or after the packets reach the target system (local proxy on the target system), this proxy is unable to hide the true IP address of the communication system.
This distinguishes him significantly from other proxies of an IP network. However, a local proxy on the source system may well help to automatically send the network request via an external proxy, with the local proxy then managing this type of redirection.
Thus contributing to the anonymization of its own IP address, possible functions of proxy protection the clients the proxy can be an interface between the private network and the public network.
The private network clients access the web server of the public network via the proxy, for example. Since the contacted target system from the public network does not send its response packets directly to the client, but sends them to the proxy, the latter can actively control the connection.