AS4643 203.202.72.0/21 CIDR and IP Range Summary.ASN: 4643 - Optus Customer NetworkHost Count: 2046Addressable IPs: 2048203.202.72.0/24203.202.73.0/24203.202.74.0/24203.202.75.0/24203.202.76.0/24203.202.77.0/24203.202.78.0/24203.202.79.0/24