An ASN (Autonomous System Number) is a unique identifier assigned to a network or group of IP prefixes controlled by a single entity (ISP, hosting company, or enterprise). Websites use ASN data to determine whether an IP belongs to a residential ISP or a commercial datacenter.
Regional Internet Registries (ARIN, RIPE, APNIC) assign ASNs to organizations that operate their own network infrastructure. Each ASN controls a set of IP ranges. When a website receives a request, it can look up the source IP in public ASN databases to identify the network owner. An IP from AS7922 (Comcast) looks residential; an IP from AS14061 (DigitalOcean) looks like a datacenter.
Most proxy users only need to understand this well enough to debug it, not configure it directly.
USER-country-de-session-task01The username carries the config: "country-de" picks the exit, "session-task01" holds it in place while ASN does its work underneath. No separate API call or handshake -- the label is the setting.
Measure this metric without a proxy first, so you know what the gateway adds versus what was already there.
This concept governs the connection to the gateway and the gateway to the target -- check both when something looks wrong.
KnoxProxy manages this at the infrastructure layer, so most jobs only need to understand it well enough to debug.
A new ISP, VPN, or office network can change how this behaves -- confirm it again after any local network change.
An anti-fraud service checks incoming request IPs against ASN databases, flagging any traffic originating from ASNs belonging to known hosting providers.
ASN detection is the primary way websites distinguish residential from datacenter traffic. Choosing proxies with ISP or residential ASNs directly affects your success rate.
Use an ASN lookup tool or query the IP against databases like MaxMind, IPinfo, or RIPE. The result shows the ASN number, organization name, and whether it is classified as residential, ISP, or hosting.
Yes, but rarely. When ISPs acquire new IP blocks or hosting companies register IPs under ISP entities, the ASN classification in databases updates over time. This is how ISP proxies maintain their residential-like classification.
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