AS4643 203.22.136.0/21 CIDR and IP Range Summary.ASN: 4643 - Optus Customer NetworkHost Count: 2046Addressable IPs: 2048203.22.136.0/24203.22.137.0/24203.22.138.0/24203.22.139.0/24203.22.140.0/24203.22.141.0/24203.22.142.0/24203.22.143.0/24