AS721 138.157.48.0/21 CIDR and IP Range Summary.ASN: 721 - DoD Network Information CenterHost Count: 2046Addressable IPs: 2048138.157.48.0/24138.157.49.0/24138.157.50.0/24138.157.51.0/24138.157.52.0/24138.157.53.0/24138.157.54.0/24138.157.55.0/24