Ads Subtracted

Detecting Ad Blockers

An advertising filter reduces the financial income of a website. Some websites ask their customers to turn off advertising blockers and hope for some understanding. On the other hand, some websites refuse to make headlines if the viewer removes the advertising.

Ad blockers can be detected because the website sends a piece of JavaScript to the browser to load an advertisement. If this operation does not succeed, some kind of advertising filter is obviously involved. The web developer can react to this information and restrict the content or activate a paywall.

Analytics services for advertising evaluate how many users were able to block the advertising and which website content was visible. Like Google Analytics, but for advertisements.

Outlook

An advertising filter does not have to sit next to your router as an SBC, but it can protect computers as a cloud service. An Ad Blocker-as-a-Service offers a great alternative if no local hardware is desired or possible. Large providers like OpenDNS [11] or Alternate DNS [12] work just like domestic ad blockers, although the cloud providers do not let you see what they are doing (i.e., the blacklists are proprietary).

You can also take an approach without the cloud or additional hardware. Routers often support filter lists and can thus restrict access to (advertising) pages. However, lists often are not updated automatically. This "Ad Blocker Light" therefore requires occasional manual refueling of the filter lists.

Conclusions

Advertising is a legitimate way to finance a website. However, many providers overdo it, and the desired content drowns in a flood of intrusive pop-ups. For this kind of website, it makes sense to use an ad blocker to make the annoying insertions disappear.

Most ad killers also protect you against data collection, block malware, and filter out content harmful to minors, if necessary, so an ad blocker is part of a basic networking toolkit.

By the way, in our lab, some websites slipped through the grid that should have been taken out by the category filter. A smart teenager or break-out-oriented employee will probably try alternative websites and possibly outwit features for the protection of minors.