Determining Proxy Server Client Requirements

Specify Private Network IP Address Ranges
Select Software for Connecting to Proxy Server

You determine the Proxy Server client requirements so that you can specify the private network address ranges and select the appropriate software for connecting to Proxy Server.

You must identify the IP address ranges within the private network so that you can specify these address ranges in the Proxy Server design. Proxy Server clients can then determine if the destination IP address in an IP packet must be sent directly to the private network destination, or forwarded to the proxy server.
The IP address ranges that you specify are stored in the local address table (LAT) file on the proxy server. When requests are sent to the proxy server, the proxy server uses the LAT to determine if the request is within the private network or on the Internet.

Specifying Private Network IP Address Ranges

For computers on the private network that do not have Proxy Server client software, you need to specify the IP address of the proxy server's private network interface as the default gateway. Because the proxy server is the default gateway for the computer, all requests that are not on the computer's local subnet are forwarded to the proxy server. The proxy server forwards the request to the Internet.
When the computers on the private network have Proxy Server client software installed, they have a local copy of the LAT file. The Proxy Server clients use their local copy of the LAT file to determine if requests are within the private network, or on the Internet. Private network requests are sent directly to the destination within the private network. Internet requests are sent to the proxy server.

1) Computers on the private network may or may not use Proxy Server client software. These 2 situations require different specifications.

2) For computers on the private network that do not have the Proxy Server Client software, you must specify the IP address of the proxy server's private network interface as the default gateway. Be sure to disable IP forwarding on the proxy server if you choose this option.

3) Because the proxy server is the default gateway for the computer, all requests that are not on the computer's local subnet are forwarded to the proxy server, which forwards the request to the internet.

4) When the computers on the private network have Proxy Server client software installed , they have a local copy of the LAT file.

5) The Proxy Server clients use their local copy of the LAT file to determine if incoming requests have destinations within the private network or on the internet.

6) Private network requests are sent to the destination within the private network without proxy server intervention, while internet requests are sent to the proxy server.