connecting to network using pat

[carl_townshend]

Can anyone tell me how this works, Say i have 5 servers at home, web, e-mail, ftp etc, and my isp points all these domain names etc to my assigned ip address. if traffic is say lookng for my web server from outside, how does my router know how to get to my webserver if all the servers are really assigned the same address from the outside ?

[spremkumar]

Hi

In addition to the PAT(overload) statement which requires to take ur local lan traffic (wkstations) out to the internet world you need to have the static translation defined based on the port numbers.

the port numbers being generally used/configured on those servers to host the respective applications.

you will have something like this for mail & web..

ip nat inside source static tcp 192.168.10.1 25 171.69.232.209 25

ip nat inside source static tcp 192.168.10.1 80 171.69.232.209 8080

for ftp again u need to have both the ports one for contorl and the other one for the data connection to be opened/mapped..

regds

[carl_townshend]

So wouldnt PAT work in this situation then ? i.e my company uses pat but traffic from outside can still reach or web and mail servers ?

[spremkumar]

Hi

Let me put it in this way that you need to have static Port translations between the local ip and the global public ip for the servers so that they same can be reached from outside world using that public ip.

And if u want to use the single pubilc ip to be used for your Local LAN wkstations to go out and access the internet world you need to have overloading configured which basically uses PORT nos to keep the track on the transactions/requests from the local LAN wkstation ips.

It will have the database built based on the ports of the inside private ip and the outside global public ip to keep the track.the main reason out here is you got to have only one public ip to access the internet world..

regds

[carl_townshend]

I have just been told that I can use PAT and port number mappings ? how its this done ?