2406:d400::/32 - CHIEF-AS-AP
inet6num: 2406:d400::/32 netname: CHIEF-AS-AP descr: Chief Telecom Inc. descr: No. 250 Yuang Guang St country: TW org: ORG-CTI1-AP admin-c: FC159-AP tech-c: CG195-AP mnt-lower: MAINT-TW-UNIGATE mnt-routes: MAINT-TW-UNIGATE mnt-by: APNIC-HM status: ALLOCATED PORTABLE last-modified: 2017-08-29T23:16:39Z source: APNIC mnt-irt: IRT-CHIEF-TW
IP address ranges, or netblocks, are groups of related IP addresses. They are usually represented as a base IP address, followed by a slash, and then a netmask which represents how many IP addresses are contained within the netblock. This format is known as CIDR. You'll also sometimes see netblocks given as a start ip address, and an end ip address, or an ip address range.
Traffic works its way around the internet based on the routing table, which contains a list of networks and their associated netblocks.