AS3257 66.253.16.0/21 CIDR and IP Range Summary.ASN: 3257 - GTT Communications Inc.Host Count: 2046Addressable IPs: 204866.253.16.0/2466.253.17.0/2466.253.18.0/2466.253.19.0/2466.253.20.0/2466.253.21.0/2466.253.22.0/2466.253.23.0/24