AS721 199.251.216.0/21 CIDR and IP Range Summary.ASN: 721 - DoD Network Information CenterHost Count: 2046Addressable IPs: 2048199.251.216.0/24199.251.217.0/24199.251.218.0/24199.251.219.0/24199.251.220.0/24199.251.221.0/24199.251.222.0/24199.251.223.0/24