AS20057 166.170.16.0/21 CIDR and IP Range Summary.ASN: 20057 - AT&T Mobility LLCHost Count: 2046Addressable IPs: 2048166.170.16.0/24166.170.17.0/24166.170.18.0/24166.170.19.0/24166.170.20.0/24166.170.21.0/24166.170.22.0/24166.170.23.0/24