Quick answer: An ASN identifies an autonomous system, a network under one administrative routing policy. ASNs are a key part of how networks exchange routes on the internet.
ASN and IP addresses
IP ranges are announced and managed by networks. An ASN can therefore help you understand which network or provider is associated with an IP block.
ASN is not a location
An ASN describes network organization and routing, not a person or exact place. A large ISP can operate one ASN across many regions.
Use ASN Lookup to inspect an address, then learn more in BGP and ASN routing.
Want to see this in practice? Check your own connection's IP, location and ISP.
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