AS17621 168.159.144.0/21 CIDR and IP Range Summary.ASN: 17621 - China Unicom Shanghai NetworkHost Count: 2046Addressable IPs: 2048168.159.144.0/24168.159.145.0/24168.159.146.0/24168.159.147.0/24168.159.148.0/24168.159.149.0/24168.159.150.0/24168.159.151.0/24