AS3257 216.133.144.0/21 CIDR and IP Range Summary.ASN: 3257 - GTT Communications Inc.Host Count: 2046Addressable IPs: 2048216.133.144.0/24216.133.145.0/24216.133.146.0/24216.133.147.0/24216.133.148.0/24216.133.149.0/24216.133.150.0/24216.133.151.0/24