AS7018 12.21.144.0/20 CIDR and IP Range Summary.ASN: 7018 - AT&T Services Inc.Host Count: 4094Addressable IPs: 409612.21.144.0/2412.21.145.0/2412.21.146.0/2412.21.147.0/2412.21.148.0/2412.21.149.0/2412.21.150.0/2412.21.151.0/2412.21.152.0/2412.21.153.0/2412.21.154.0/2412.21.155.0/2412.21.156.0/2412.21.157.0/2412.21.158.0/2412.21.159.0/24