AS23520 190.242.136.0/21 CIDR and IP Range Summary.ASN: 23520 - Columbus Networks USA Inc.Host Count: 2046Addressable IPs: 2048190.242.136.0/24190.242.137.0/24190.242.138.0/24190.242.139.0/24190.242.140.0/24190.242.141.0/24190.242.142.0/24190.242.143.0/24