AS17638 221.239.104.0/21 CIDR and IP Range Summary.ASN: 17638 - ASN for TIANJIN Provincial Net of CTHost Count: 2046Addressable IPs: 2048221.239.104.0/24221.239.105.0/24221.239.106.0/24221.239.107.0/24221.239.108.0/24221.239.109.0/24221.239.110.0/24221.239.111.0/24