Every IP address on the public internet belongs to an autonomous system — a network, identified by an ASN, that announces routes for it. Your ISP has one. Big cloud providers have several. When a target site sees traffic, the ASN behind the IP is one of the cheapest, most reliable signals it can read.
Why targets care
Datacenter ASNs are well catalogued. If a thousand requests arrive from a thousand different IPs that all announce from the same hosting ASN, a target does not need sophisticated fingerprinting to conclude they are related. Residential and ISP proxies command premium prices precisely because their exits sit in consumer ASNs, mixed in with ordinary subscriber traffic.
Why buyers should care about the distribution
A pool advertised as fifty thousand IPs is less impressive if most exits concentrate in three ASNs. Concentration means a single blocklist entry, or one upstream deal ending, can invalidate a large share of the pool at once. Diversity is resilience: across ASNs, across the networks those ASNs peer with, and ideally across the registries that allocated them.
- Ask providers how many distinct ASNs back the pool you are buying, not just how many IPs.
- Ask whether the ASN mix matches the product label — an "ISP" line exiting from hosting ASNs is mislabeled.
- Watch our per-line ASN accuracy check: it verifies exits actually announce from the networks the provider declares.
We grade what we observe. When our checks resolve the ASN behind each observed exit, that evidence feeds the trust & sourcing dimension — one of the six grades you can re-weight with the scoring lens.