AS18937 National Monitoring Center

NMC - National Monitoring Center · registered in the United States

IPv4 addresses5122 prefixes · <0.001% of announced IPv4

Rank in United States#10,888largest network in US by IPv4 space, of 18,338 · <0.01% of US

Rank worldwide#50,137of 79,396 networks with IPv4

IPv6noneno IPv6 routes announced

CountryUnited States18,679 ASNs registered there

Open AS18937 in ASN lookup Look up an IP in this network (12.197.228.1) All networks in United States

IPv4 prefixes

All 2 prefixes, in address order.

12.197.228.0/24
67.129.151.0/24

Similar-sized networks in United States

ASNNameIPv4 addresses

AS18902#10885 CMC-II-LLC - CMC II, LLC512

AS18903#10886 LENDINGTREE - LENDING TREE512

AS18920#10887 HEI - Hawaiian Electric Industries, Inc.512

AS18949#10889 BARTELL-CORP-INTERNET - Bartell Hotels, A California Limited Partnership512

AS18952#10890 BVR-AS - Big Valley of Pomo Indians of the Big Valley Rancheria California512

AS18955#10891 TWEA-AS - Treasury Wine Estates Americas512

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