AS11990 Unlimited Net, LLC
2605:fa80::/36 - UNLIMITED-NET
V6NetHandle: NET6-2605-FA80-1 OrgID: UNL-9 Parent: NET6-2600-1 NetName: UNLIMITED-NET NetRange: 2605:FA80:: - 2605:FA80:FFF:FFFF:FFFF:FFFF:FFFF:FFFF NetType: allocation OriginAS: 11990 Comment: http://www.unlimitednet.us RegDate: 2015-02-20 Updated: 2015-09-09 Source: ARIN OrgID: UNL-9 OrgName: Unlimited Net, LLC CanAllocate: Street: 3129 25th St. Street: Suite 135 City: Columbus State/Prov: IN Country: US PostalCode: 47203-2436 RegDate: 2012-04-20 Updated: 2017-01-28 ReferralServer: rwhois://rwhois.unlimitednet.us:4321 OrgAbuseHandle: ABUSE3406-ARIN OrgAdminHandle: CANAD4-ARIN OrgTechHandle: NOC12589-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.