asn-infrastructure-mapping

To find IP ranges owned by an organization, you pivot from target domains to extract Autonomous System Numbers (ASN) and retrieve associated CIDR blocks. This ASN mapping process reveals full network infrastructure when standard subdomain enumeration misses sibling top-level domains or subsidiary networks.

Subdomain enumeration fails to uncover all IPs because it misses infrastructure hosted on sibling top-level domains, separate ASNs for acquired entities, and services running on non-standard ports. ASN and CIDR range extraction is required to discover these hidden network assets across the organization's full footprint.

The best way to map full network infrastructure from a single domain is pivoting through ASN lookup to extract CIDR ranges, performing reverse DNS hostname mapping on those IP ranges, and scanning for live web services. This reveals the complete domain-to-IP-to-service architecture.

Yes, you can discover sibling domains on alternate top-level domains through TLD expansion during reconnaissance. This technique identifies separate, potentially less secure infrastructure hosted on alternate TLDs like .io or .dev that standard subdomain enumeration overlooks.

Yes, reverse DNS mapping works on large CIDR ranges extracted from ASN data. By applying reverse DNS hostname mapping across discovered CIDR blocks, you can identify live web services and visualize the full infrastructure architecture, even when services run on non-standard ports.

You should use ASN mapping instead of standard subdomain enumeration when reconnaissance needs to uncover IPs on sibling top-level domains, separate ASNs for subsidiaries, or services hosted on non-standard ports. It provides full IP range discovery that standard enumeration cannot achieve.