Chrome browser sending Keep-Alive packets?

You may want to check out this article regarding keep-alive timeouts:

Interestingly one of the other things I noticed while doing this test with Wireshark is that after 45 seconds, Chrome would send a TCP keep-alive packet, and would keep doing that every 45 seconds until the 5 minute timeout. No other browser would do this.

My guess would be that Chrome had opened a connection to the Google Instant server (probably as soon as you typed something in the browser bar) and then is sending the keep-alives to keep the connection open until the browser is finally closed. As mentioned in the article above, many NAT routers will close an idle connection after 2 minutes so various browsers will send keep-alives on intervals shorter than that to keep connections open.

@Sathya: I don't think so. My version is up to date and as Spiff said, the IPs don't appear to belong to Google. – nmc 2 days ago

Erm... http://74.125.226.92 and http://74.125.226.34/ are Google for sure. ;)

It's either related to Google Updater or Google Instant, just to keep a connection with Google open...