ASN (Autonomous System Number)
A unique identifier assigned to a network operator, used to determine if an IP belongs to a datacenter, ISP, or residential network.
An Autonomous System Number (ASN) is a globally unique identifier assigned by IANA to a network operator. ASNs are how the internet routes traffic and how websites determine the source of an IP address.
For proxies, ASN is critical: anti-bot systems check the ASN to classify traffic. A request from ASN AS7922 (Comcast) will be treated very differently from AS16509 (Amazon AWS). ISP proxies are valuable because they come from residential ISP ASNs, while datacenter proxies use cloud provider ASNs.
How it works
Every IP block on the internet belongs to exactly one ASN at any moment. The mapping is public via BGP routing tables and via the WHOIS/RDAP databases that anti-bot vendors lift into their classifiers. When a request lands on a protected site, the edge stack runs a reverse lookup on the source IP, retrieves the ASN, and feeds it into a reputation model alongside fingerprint, behaviour, and geo signals.
ISP ASNs like AS7922 Comcast, AS3320 Deutsche Telekom, or AS17676 Softbank carry consumer reputation and pass nearly every classifier on reputation alone. Cloud ASNs like AS16509 AWS or AS14061 DigitalOcean are flagged on sight by Akamai Bot Manager, Cloudflare Bot Fight, and DataDome. Murphy's ISP pool is sourced from residential ISP ASNs across 15+ countries; the residential pool inherits the ASN of whichever home network is relaying the request at that moment.
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