Address Transalation

[gauravbajaj]

HI Linux grp
When a webserver responds  to a clients request  through a proxy server , how does ithe destinition-address gets translated into clients real Ip- address at the proxy server.

bye
Gaurav

[Ricky]

well .. no address i translated.. adress translation only takes place in NAT or routing.

[gauravbajaj]

ya i know its with NAT
but how?
can u explain

[gauravbajaj]

hi ricky,
i know proxy server with NAT always add its  ip-address to the client packet , so that the outside users thinks that the packet is of proxy server only(this is through NAT )  but can u tell the reverse process i.e when client gets the packet from the webserver through the Proxy server, then how its destionition IP ADDRESS gets subtituted?
that is my question, i hope now its clear
tell me if u know this process, otherwise i will try from other sources

gaurav

[Ricky]

well.. last time i was in hurry..
The NAT and proxy are totally different.. here you are saying NAT proxy ! there is nothing like that..
You may be thinking about Transparent proxy..
But first you see how proxy server work !!

Well in case of proxy server... it acts as webserver for your clients.. your clients ask him for data and in return he ask the internet.

in case of NAT.. your client sends the request , then its ip address are changed only .. ie header info with the address of gateway so that it came back to your computer ie gateway, then again get changed to client's address and reaches there..

[gauravbajaj]

ya i know u can't understand my problem,
NAT forwarding we do with iptables command using NAT
like
iptables -t NAT........
but in reverse how gateway changed to clients address?

You were saying that when it come back to your computer i.e gateway, then again get changed to client's address & reaches there but how ?
this is my question,? tell me how this happens

Tell me if u know ?
gaurav