How to Protect your Internet Anonymity and Privacy/Securing your Browser

This explains explains in detail how to use proxy servers to gain anonymity and privacy by configuring one's browser to use a network proxy.

Internet Explorer

 * Start Internet Explorer
 * Click Tools &rarr; Internet Options to open that dialog box (window)
 * Click the Connections tab
 * For Dial-up or Virtual Private Network
 * Click to select the appropriate entry used to connect to the Internet
 * Click Settings to open that dialog box (window) (left screen capture below)
 * For LAN (e.g., broadband)
 * Click LAN Settings to open that dialog box (window) (right screen capture below)
 * Under Proxy server
 * Click to check Use a proxy server for your LAN...
 * Click to check Bypass proxy server for local addresses
 * Click Advanced... to open the Proxy Settings dialog box (window)
 * Under Servers, in Type HTTP
 * In Proxy address to use enter planetlab-1.cs.princeton.edu
 * In Port enter 3128
 * Click OK to close the dialog box (window)
 * Click OK to close the Settings dialog box (window)
 * To turn the proxy OFF : (Configuration will be saved for later reuse)
 * Open the Settings dialog box (using the above procedure)
 * Click to uncheck Use a proxy server for your LAN...
 * Click OK to close the Settings dialog box (window)


 * To turn the proxy back ON : (Using saved configuration)
 * Open the Settings dialog box (using the above procedure)
 * Click to check Use a proxy server for your LAN...
 * Click OK to close the Settings dialog box (window)

Mozilla Firefox

 * Start Mozilla Firefox
 * Click on Tools &rarr; Options to open the Options dialog box
 * Click on Connection Settings
 * For LAN (e.g., broadband)
 * Click on Manual Proxy Configuration
 * In the HTTP Proxy: textbox, enter : planetlab-10.cs.princeton.edu and in the "Port:" textbox, enter 3128
 * Click on OK to close the Connections dialog box
 * Click on OK to close the Options dialog box


 * To turn the proxy OFF : (Configuration will be saved for later reuse)
 * Open the Connection Settings dialog box (using the above procedure)
 * Select Direct Connection To Internet
 * Click OK to close the two dialog boxes


 * To turn the proxy back ON : (Using saved configuration)
 * Open the Connection Settings dialog box (using the above procedure)
 * Click to check Manual Proxy Configuration
 * Click OK to close the two dialog boxes

Mozilla Firefox version 3.6

 * Start Mozilla Firefox
 * Click on Edit &rarr; Preferences to open the Preferences dialog box
 * Select the Advanced control panel and Network tab
 * Click on Connection Settings
 * For LAN (e.g., broadband)
 * Click on Manual Proxy Configuration
 * In the HTTP Proxy: textbox, enter : planetlab-10.cs.princeton.edu and in the "Port:" textbox, enter 3128
 * Click on OK to close the Connection Settings dialog box
 * Click on Close to close the Preferences dialog box


 * To turn the proxy OFF : (Configuration will be saved for later reuse)
 * Open the Connection Settings dialog box (using the above procedure)
 * Select No proxy
 * Click OK and Close to close the two dialog boxes


 * To turn the proxy back ON : (Using saved configuration)
 * Open the Connection Settings dialog box (using the above procedure)
 * Click to check Manual Proxy Configuration
 * Click OK and Close to close the two dialog boxes

Opera
Opera uses the Internet Explorer proxy. Or in other words it uses the system proxy.

Chrome
Start Google Chrome
 * Click Customize and control Google Chrome --> Tools to open the Google Chrome Options dialog box.
 * There will be three tabs - Basics- Minor Tweaks - Under the hood.
 * Select Under the hood tab.
 * Click Change proxy setting button under  Network.
 * Internet Options dialog box will be displayed.
 * Remaining steps are similar to Internet Explorer.

Plug-ins and Add-ons
Any plug-ins and add-ons are granted by you the same privilege as external applications on your computer. They do not observe the proxy settings at your browser. Generally they have the same access to the Internet as your browser. All these applications need to do is to connect to their own server and reveal your true IP. The Firefox NoScript add-on can reduce the risk by disabling these plug-ins by default, until you white-list the websites.

These plug-ins are typically referred to collectively at the browser as Javascript. However, Javacript codes as downloaded from webpages are executed via the browser, and do not have elevated privileges. This is different from the Javascript used in, say, add-ons for Firefox. These scripts has total access to your computer just as any applications, and browser based defense such as NoScript has no effect.

Browser Fingerprints
Even with all the anonymity precautions, your browser may still leaves the same fingerprint on different hosts. Fingerprints are deduced from seemingly harmless features - installed fonts and add-ons - but these are rather unique, and can be used to show that the same person make the posts on the forum as different users. A very power adversaries can use it to link the person paying his DMV fee online at home, with the person accessing a secret email account. The IP addresses doesn't matter, if your adversary can order massive fingerprinting and have the capacity to match them sooner or later.

The most effective way to avoid defeat fingerprinting is to use setup different profiles, such as that on Firefox - one for public everyday life, one for special interests that could identify you, and one for your secret life, etc. In each profile, you can store cookies, bookmarks and enable history for convenience. You should use add-ons to fake browser headers, install different add-ons and fonts. Use different proxies or VPN.