AS17924 121.203.64.0/21 CIDR and IP Range Summary.ASN: 17924 - Smartone Mobile Communications LtdHost Count: 2046Addressable IPs: 2048121.203.64.0/24121.203.65.0/24121.203.66.0/24121.203.67.0/24121.203.68.0/24121.203.69.0/24121.203.70.0/24121.203.71.0/24