On 12/07/2011 07:15 AM, Warp wrote:
> Invisible<voi### [at] devnull>  wrote:
>> I've never installed this or any similar system under the assumption
>> that it is almost guaranteed not to work.
>
>    Just try it. You'll be pleasantly surprised.

Well, yes, there is that...

(In a stunning turn of events, I actually have some work to do today. 
Yeah, I know. Imagine that...)

>    It doesn't need to do smart filtering. It only needs a blacklist. Said
> list updates automatically.

I don't get how that can work.

If it blacklists the server IP addresses, all you need to do is copy the 
ads to another server and the blacklist is defeated. As a bonus, if you 
put the ads on the same server as the genuine content, then you *can't* 
blacklist the server or you'll be blocking genuine content.

If it blacklists the MD5 hash of the ad files, just take each image and 
change 1 pixel. The MD5 hash is now completely different, but the ad 
still works just as well.

If it blacklists the file /name/, it's trivial to rename it.

If it blacklists the code fragments used to link to the adverts, just 
make any trivial cosmetic change to the code and you've defeated the 
blacklist.

All of this on top of the fact that blacklists are generally ineffective 
anyway. (If you filter anything - spam, malware, adverts, whatever - 
based on a blacklist, then that blacklist will always be out of date and 
you need an army of people to constantly update it for you.)

Post a reply to this message