Bypass an ad blocker

Bypass an ad blocker

Linket was awarded a patent on how to avoid an ad blocker for mobile apps. This is important because ads are one key way for a mobile app to monetize its audience. The app itself could be free to download, but that just begs the question of how it makes money. What emerged in recent years is for the app to show ads. And to sell subscriptions to avoid the ads. The ads and subscriptions are 2 sides of the same coin.

But users sometimes (often?) detest ads. They retaliate by installing an ad blocker on their phones. The figure shows Jill with her phone. On it is an ad blocker program. Or equivalently, the ad blocker runs on her phone carrier. In either case the blocker surveils incoming traffic to her phone. It looks for a sender address that is on a blacklist of spammers or ad servers. And it looks inside message bodies for links with domains or raw addresses in the blacklist. So when the app server calls the ad server for an ad to send to Jill’s phone, the blocker will detect it and not forward it to her phone if the blocker is on the carrier’s computer. If the blocker is on her phone, it will not show the ad. The red line shows an ad coming from the ad server to Jill. But the blocker stops it.

This is where Linket comes into play. Jill interacts with Bob through the app. They may or may not be near each other; it does not matter. The app server needs to push ads to Jill and Bob. It detects that Bob gets the ads. Maybe he doesn’t mind them and has no ad blocker on his phone or carrier. Or maybe he connects to the Internet via a hot spot that has no ad blocker installed.

The ad server sends its ad to the app instance on Bob’s phone. These are the green arrows 1 and 2. The ad displays to Bob. His app also makes a modded copy. The links in the copy that used to point to the ad server now point to Bob’s Internet address and to something called a port number. (It’s part of the address.) His app listens on that port. His app sends the modded ad to Jill’s app. Suppose her blocker runs on her phone. It inspects the ad, which to it is just some arbitrary bits. It is trying to see if this set of bits is an ad. When it finds a link, the address in the link is a raw Internet address of Bob’s phone. The address is unlikely to be on a blacklist. So the blocker lets the ad be shown to Jill, in green arrow 4.

If Jill likes the ad and clicks it, this makes a message as purple arrow 5. Assuming that the blocker inspects outgoing messages, it checks the destination address against its blacklist. But the address is of Bob’s phone. So the blocker lets the message continue as purple arrow 6. At his phone, his app gets the message, and replaces the destination with the ad server’s address. The message goes as purple arrow 7 to the ad server. If there is more interaction between the ad server and Jill, this is mediated by Bob’s app.

Why is Bob’s address not on a blacklist? When he connects to the Internet via his carrier or hot spot, his phone is assigned a temporary address, like 10.210.15.83. After he uses it for some time, the carrier or hot spot takes it back and re-assigns it to another user. The address is part of a set of addresses used for this purpose. If a blocker has the address in its blacklist, this can target innocent users who just get that address temporarily. A blacklist works best against “normal” advertisers, who have fixed domains like buyMyGoods.com. These domains sit at addresses constant over months. Whereas a blocker blocking Bob’s temporary address leads to collateral damage.

A crucial assumption is that the apps talk to each other directly. The apps know each other’s network address. Not all multiuser apps do this. Some interact exclusively via the app server. But a virtue of the apps talking directly, and still occasionally checking in with the server is that this reduces the workload of the server, in computation and bandwidth. The second virtue is that this enables this patent, to activate ads for both users.

To be sure, some readers will read this from the vantage of a mobile user who does not want ads. But if you work for an app firm that needs ads, this can be useful.

Contact me for licensing information. (wesboudville@linket.info)

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