Skip to content


What is a PAC file?
A proxy auto-configuration (PAC) file defines how a web browser can automatically choose an appropriate proxy server for fetching a given URL.
The file is based on Javascript, uses relatively simple syntax and modern browsers such as Internet Explorer, Firefox, Opera, Chrome and Safari support the PAC standard.
What is WPAD?
The Web Proxy Autodiscovery Protocol (WPAD) is a method supported by modern web browsers to locate a proxy auto-configuration (PAC) file automatically and use this to configure the browser’s web proxy settings.
The protocol utilizes DHCP and/or DNS in order to locate the PAC file. Whilst WPAD is yet to become an official internet standard, support in browsers is widespread.
Here is kind of official document from Microsoft;
Two websites explain in detail:
Two example sites:
No comments yet

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: