Explainer: What an autonomous system is and why ad tech uses it to flag bot traffic
· 50m ago · Originally reported by PPC Land
An autonomous system is a network or group of IP prefixes operated under a single routing policy and identified by its own number. Ad tech platforms use AS information to flag traffic originating from data centres and hosting networks, which is a common indicator of automated bot activity rather than real human users.
Why it matters
AS-level checks are a foundational signal in invalid traffic detection, so understanding them helps anyone in advertising see how platforms separate genuine audiences from automated clicks.
Explain it like I’m new here
An autonomous system is like the return address on a letter — if a click's 'address' is a server warehouse instead of someone's home, ad systems treat it as a likely bot.
Terms in this story
Ad tech
Ad tech is the software and infrastructure that decides which ad appears where, buys and sells that ad space, delivers the ad, and measures what happened afterwards.
Bot traffic
Bot traffic is visits, ad impressions or clicks generated by automated software rather than people, ranging from honest search crawlers to fraudulent bots built to look human.