2600:3000:1b00::/40 - VIAWEST-IPV6-BLK-1
V6NetHandle: NET6-2600-3000-1 OrgID: VINS Parent: NET6-2600-1 NetName: VIAWEST-IPV6-BLK-1 NetRange: 2600:3000:: - 2600:3007:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF NetType: allocation OriginAS: 36123, 18565, 32868, 13845, 29699, 13649, 10628 RegDate: 2010-11-10 Updated: 2012-03-02 Source: ARIN OrgID: VINS OrgName: ViaWest CanAllocate: Street: 8809 Lenox Pointe Drive, Suite G City: Charlotte State/Prov: NC Country: US PostalCode: 28273 RegDate: 2000-04-24 Updated: 2019-05-21 OrgTechHandle: NETWO1470-ARIN OrgNOCHandle: ZP63-ARIN OrgAdminHandle: DTR20-ARIN OrgAbuseHandle: ZP76-ARIN Source: ARIN
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.