Wikipedia:Bypassing TPG Internet's open intercepting proxies

This is an essay, a page containing the advice or opinions of one or more Wikipedia contributors. Essays may represent widespread norms or minority viewpoints, and they may be heeded or not based upon your judgement and discretion.

TPG Internet is an Australian ISP that uses intercepting proxies that intercept all HTTP traffic in hopes that its users' requests go to the same page often. This is done so that pages retrieved from the Internet are cached in hopes that the same user or a different user will read the same page, in which case the proxy server will discard the user's request and then respond to the user with its own copy of the page. This reduces costs for TPG Internet by preventing repeated traffic to the same site from being generated. Unfortunately, some of these proxies are misconfigured and allow anyone to use them, making them open proxies. Therefore, Wikipedia must block them in order to stop vandals and other Wikipedia abusers. Here are instructions to cause your browser to use TPG Internet's correctly configured closed proxy:

If you use Internet Explorer, go to your Internet Properties control panel. Click on the Connections tab. Click the LAN Settings button at the bottom of the resulting page in the dialog box. Check the box "Use a proxy server for your LAN (These settings will not apply to dial-up or VPN connections).". Enter proxy.tpg.com.au in the address field and 80 in the port field, and check the box "Bypass proxy server for local addresses".

If you use Firefox, go to the Tools menu and select the Options command. Then click the Advanced button with the gear on top. Click the Network tab. Click the "Settings..." button which is within the "Connection" box. Click the "Manual proxy configuration" radio button. Enter proxy.tpg.com.au in the HTTP proxy box and 80 in the port field, and change the "No Proxy for:" box to read localhost, 127.0.0.1, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 so that your home router and networking equipment are accessed directly.

If you use a browser that cannot use a proxy, edit Wikipedia through the secure Wikipedia server at https://secure.wikimedia.org/wikipedia/en/wiki/ because SSL and TLS-encrypted traffic cannot not go through proxies unless they are the place where encryption and decryption are performed because there is no way to cache this encrypted traffic without performing a man-in-the-middle attack, which both SSL version 3 and TLS are able to thwart. (SSL version 2 is vulnerable to this attack, so it is best to disable this version of SSL if possible.) If the proxy server is the point of encryption and decryption, then the user must hope that the proxy is trustworthy because this is basically a man-in-the-middle attack that is either consented to or forced on by the administrator.