Why so?
Do the tracking inside the browser, send it back, render the ad server side and send it to the user?
It's already being implemented in many places.
Do the tracking inside the browser, send it back, render the ad server side and send it to the user?
It's already being implemented in many places.
That said, I think minimally-tracked (i.e based on what the website you're using knows about you) server side ads would be a great step forward for both user privacy + ethical content consumption, I just don't see advertisers jumping at the opportunity.
User goes to news.com, which loads ads from adserver.com. Adserver.com sees the cookie, and shows the ads about shoes.
If you do everything on the server side, shoes.com won't be able to place a global tracking cookie. So when the user goes to news.com, they'll have to see the generic ad, and not a targeted one.
User goes to news.com. adserver.news.com loads ads from adserver.com . Adserver.com checks cookie from adserver.shoes.com and and generates ads server side and shows it with the news.
1. This is not possible from server-side. The way cookies work, cookies set by adserver.shoes.com are only visible from documents hosted on *.shoes.com domains. And if the tracking is done client-side, by image, iframe or some other remote call, then this is trivially detected and blocked by adblocker.
2. How did "adserver.com" knew to check for "adserver.shoes.com" cookies? there might be hunderds clients, and trying to load cookies from every domain (adserver.shoes.com, adserver.computers.com, adserver.travel-to-india.com and so on) will take way too long.
Like Google AMP.
Client site rendering can easily be blocked by just domain blocking.