2620:1f:8004::/48 - CLOUDFLOOR6
V6NetHandle: NET6-2620-1F-8000-1 OrgID: MUL-44 Parent: NET6-2620-1 NetName: CLOUDFLOOR6 NetRange: 2620:1F:8000:: - 2620:1F:800F:FFFF:FFFF:FFFF:FFFF:FFFF NetType: assignment OriginAS: 10908 RegDate: 2011-04-19 Updated: 2015-07-09 Source: ARIN OrgID: MUL-44 OrgName: CloudfloorDNS CanAllocate: Street: 155 North Lake Avenue Street: Suite 900 City: Pasadena State/Prov: CA Country: US PostalCode: 91101 RegDate: 2015-06-02 Updated: 2018-06-13 OrgAbuseHandle: CRONS-ARIN OrgAdminHandle: CRONS-ARIN OrgTechHandle: CRONS-ARIN OrgNOCHandle: CRONS-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.