2001:1900:2254::/48 - LVLT-IPV6
V6NetHandle: NET6-2001-1900-1 OrgID: LPL-141 Parent: NET6-2001-1800-0 NetName: LVLT-IPV6 NetRange: 2001:1900:: - 2001:1900:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF NetType: allocation RegDate: 2004-01-07 Updated: 2018-02-20 Source: ARIN OrgID: LPL-141 OrgName: Level 3 Parent, LLC CanAllocate: Street: 100 CenturyLink Drive City: Monroe State/Prov: LA Country: US PostalCode: 71203 RegDate: 2018-02-06 Updated: 2018-02-22 OrgAbuseHandle: IPADD5-ARIN OrgAdminHandle: APL7-ARIN OrgTechHandle: IPADD5-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.