An Autonomous System Number (ASN) is a unique identifier assigned to a collection of IP networks under the control of a single organization. Think of it as a "network ID" that identifies who manages a block of IP addresses on the internet.
Why ASN Matters
- Network Ownership: Identifies which company or organization controls an IP range.
- Routing: ASNs are essential for BGP routing between internet service providers.
- Security Research: Helps identify the origin of traffic and potential threats.
- Network Analysis: Understanding internet topology and peering relationships.
Common Use Cases
Security professionals use ASN lookups to investigate suspicious IPs, identify hosting providers, and understand network relationships. For example, if you ping an IP address and want to know who owns that network, an ASN lookup provides that information.
You can also use our IP Lookup tool for geolocation data or WHOIS Lookup for domain registration details.