AS27451 US Oncology, Inc.

USO-ASN - US Oncology, Inc. · registered in the United States

IPv4 addresses7682 prefixes · <0.001% of announced IPv4

Rank in United States#9,567largest network in US by IPv4 space, of 18,338 · <0.01% of US

Rank worldwide#44,099of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited States18,679 ASNs registered there

Open AS27451 in ASN lookup Look up an IP in this network (38.68.63.1) All networks in United States

IPv4 prefixes

All 2 prefixes, in address order.

38.68.63.0/24
206.203.80.0/23

Similar-sized networks in United States

ASNNameIPv4 addresses

AS27253#9564 ASN1 - AMERICAN RESIDENTIAL SERVICES L.L.C.768

AS27358#9565 TRUSTMARK-INSURANCE-INTERNET - TRUSTMARK INSURANCE CO.768

AS27377#9566 FTICON-909 - FTI CONSULTING768

AS27477#9568 POLAR-PUBLIC-HUB-POP-ASN - IBM768

AS27548#9569 USAN-AS-A - United States Advanced Network Inc.768

AS27560#9570 ULTCO - Universal Leaf Tobacco Company Inc.768

IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources