V6NetHandle: NET6-2600-80C-D20-1 OrgID: BISUDC Parent: NET6-2600-800-1 NetName: TBD NetRange: 2600:80C:D20:: - 2600:80C:D20:FFFF:FFFF:FFFF:FFFF:FFFF NetType: reassignment Comment: Addresses within this block are non-portable. RegDate: 2012-09-05 Updated: 2012-09-05 Source: ARIN OrgID: BISUDC OrgName: BIS CanAllocate: Street: 1401 Constitution Avenue, NW, Room 6712 City: Washington State/Prov: DC Country: US PostalCode: 20230 Comment: http://www.bis.doc.gov/ RegDate: 2011-08-26 Updated: 2015-10-05 OrgNOCHandle: WARDJ2-ARIN OrgTechHandle: WARDJ2-ARIN OrgAbuseHandle: WARDJ2-ARIN OrgAdminHandle: WARDJ2-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.