Targeted Advertising

Ever been interested in a certain product, and done some Google research about it?  Then, for days afterwards, whenever you go to a website, you see ads for that very same thing?  What a coincidence!  Well, actually, it is not a coincidence.  It is called Targeted Advertising.  Whenever you browse to a certain site, the site can store “cookies” on your computer.  These are not cookies you can eat (I know, what a bummer).  Browser “cookies” are small bits of information that your browser stores, based on instructions sent from the websites you visit.  Once a cookie is stored, if you browse to that site again, your browser can read the cookie, feed that information back to the website, and voila, the website content is magically tailored for you.  That is targeted advertising.

I’ve already discussed “unsolicited incoming packets.”  Now that you have browsed to the website, your traffic is not “unsolicited” anymore, so your firewall won’t block it.  If some program (ANY program) on your computer initiates a connection to the Internet, the request (and the rest of the Internet “conversation”) is no longer “unsolicited”, and your firewall will not block the traffic.  This goes for all the third-party ad servers that are referenced in the webpage you browsed to.  Now, you didn’t ask to go to the ad server, but it is referenced in the webpage you did ask for, so it has the same access to your information that your browser has.  I’m not sure of the security implication of this, with browser sandboxes and all, but after the earlier experiment with TOP_SECRET.html, I am nervous about it.

The New York Times has a good article about this called “Resisting the Online Tracking Programs.”  It points to another article titled “Removing and Blocking Ad Cookies, Browser by Browser.”  I recommend that you review these two articles and implement some (or all) of their suggestions. Make sure your browser is also configured securely.

One method I just tried is to install AdBlock Plus (   I sure hope it works.  I’m keeping my fingers crossed…

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