AS4766 121.138.40.0/21 CIDR and IP Range Summary.ASN: 4766 - Korea TelecomHost Count: 2046Addressable IPs: 2048121.138.40.0/24121.138.41.0/24121.138.42.0/24121.138.43.0/24121.138.44.0/24121.138.45.0/24121.138.46.0/24121.138.47.0/24