Gmail announced via their official blog an update to what was Gmail Helps with your Security Concerns, Pt. 1, which improved your ability to detect if somebody else was accessing your Gmail account. They accomplished this by showing you what IP addresses had recently been active on your account and allowed you to sign out any remote sessions. Well now, they’ve made things better. They use some IP location techniques to look up each IP address that has accessed your account and give a rough location of where that computer/IMAP server/smartphone is and display that additional information. Taking things a step further, they look at the information and will more prominently warn you if your account was recently accessed hundreds of miles away from where it was last checked.
The last 5 IP addresses that your account was accessed from are listed. When I check my activity I can account for all of the IP addresses: my home computer, my work computer, a firefox addon (gmail notifier), and my smart phone. You can access the full list by clicking the Details link at the bottom of any Gmail window.
(Images courtesy Google’s blog announcement)
You can disable the notification this will generate in the recent activity window. Click the ‘change’ link at the bottom about Alert preference. It takes about a week for this setting to change to help protect from the bad guys being the ones to turn off the notification. You can read more about the Last account activity feature including today’s additions in this Gmail Help article.
Hopefully, you’ll never see the notification in action.