AS23520 72.252.40.0/21 CIDR and IP Range Summary.ASN: 23520 - Columbus Networks USA Inc.Host Count: 2046Addressable IPs: 204872.252.40.0/2472.252.41.0/2472.252.42.0/2472.252.43.0/2472.252.44.0/2472.252.45.0/2472.252.46.0/2472.252.47.0/24