security_geek - 5:05 am on Mar 8, 2006 (gmt 0)

I've noticed this too but its probably independent of the browser. When you visit a link your browser does a DNS lookup for the IP address. Both your browser and your IP stack remember the IP address so they don't have to keep bugging the DNS server. The computer's IP stack doesn't remember this very long but the browser can. So if you keep hitting google in Firefox you'll probably keep hitting the same DC. But wait a couple minutes and open IE and it will likely get a different IP address for a different DC, giving you different results.

Firefox even has plugins where you can adjust how long it keeps this information (eg; FasterFox). On a Windows 2000,XP,2003 computer you can clear the IP stack DNS setting from a command prompt by typing ipconfig /flushdns .

Try going to a command prompt (assuming Windows) and type "ping www.google.com" (without the quotes), make note of the IP address, type "ipconfig /flushdns", ping www.google.com again, note the IP address. You may have to do this a few times but you'll eventually get a different IP address.