One of the most popular articles here that I wrote back in very-early 2010 is The Mysterious 1e100.net. You might want to read that before reading this rest of this one for reference. That article has been seen many thousands of times from people wanting to know what the hell [subdomain].1e100.net addresses keep popping up in their network traffic over and over again.

There is only one way to block 1e100.net in its near-entirety, and that’s with two router-based firewall rules. There is no way to block 1e100.net completely via any setting in a browser or add-on/extension. You can have NoScript, FlashBlock, Ghostery running all at once, and 1e100.net will still make connections. If you have other Google products like Google Talk, Picasa or Google Earth to name a few, 1e100.net shows up. If you subscribe to any RSS feeds that are FeedBurner based, that uses 1e100.net. If you have the Google Chrome browser installed, a background process (at least in Windows) periodically connects with 1e100.net for updates. And even if you have the Chromium browser installed without the auto-udpater, the browser “phones home” three times to 1e100.net on every browser startup.

Then of course there are mountains of web sites (including this one) that uses Google Analytics for site traffic monitoring. On top of that there are many sites that use scripting via googleapis.com for site functionality.

The vast majority of 1e100.net public IPs are in the ranges of 74.125.0.0 through 74.125.255.255 and 173.194.0.1 through 173.194.255.255.

You could, if so desired, block all these IPs with your router admin program.

Here’s an example of a firewall rule:

firewallrule

What the above literally translates to is, “For all router-assigned IPs on all ports, deny access to 74.125.0.1 through 74.125.255.254”. I named it “Google 1” and the second range of IPs “Google 2”.

On my particular router, the end portion of an IP address can’t be a 0 or 255, hence the reason it’s shown as 1 and 254 above.

When these two rules are in effect, 99% of Google content is blocked. I say 99% because there are other blocks of IPs Google owns for other services they have.

What happens when you block Google entirely?

Your internet experience will be significantly limited.

YouTube won’t work. Gmail won’t work. Many web sites that use googleapis.com won’t work. Google search will only sort-of work.

You really get to see how deep Google permeates itself throughout the internet when you actually block their 1e100.net IP ranges. A lot of stuff breaks, and it’s for that reason I don’t recommend blocking their IPs.

I’ve seen many forum threads across the internet where a bunch of people who monitor their personal network traffic are all asking the same thing: “HOW DO I BLOCK *ALL* OF GOOGLE?” Well, now you have your answer. Mostly. Block the two IP ranges mentioned above via your router, and the vast majority of 1e100.net connections are stopped cold.

Again I will say that I don’t recommend blocking Google this way because a lof of stuff you use on the internet will break.

How do you know your block is working?

Download TCPView and launch it.

Go to your web browser and load www.youtube.com, a Google property.

You will immediately see a ton of connections to 1e100.net in TCPView:

tcpview1

Enable your firewall rules in your router.

Close your browser and restart it, then try to load youtube.com again.

This is what will happen in TCPView:

tcpview2

Instead of ESTABLISHED, you’ll see SYN_SENT, which means a connection is being attempted. But the connection will never complete because it’s blocked. When you see a bunch of SYN_SENT’s for [anything].1e100.net, your firewall rules are working.