2620:31:8000::/48 - RTI-IPV6-1
V6NetHandle: NET6-2620-31-8000-1 OrgID: RTI Parent: NET6-2620-1 NetName: RTI-IPV6-1 NetRange: 2620:31:8000:: - 2620:31:8000:FFFF:FFFF:FFFF:FFFF:FFFF NetType: assignment OriginAS: 81 RegDate: 2011-05-04 Updated: 2012-02-24 Source: ARIN OrgID: RTI OrgName: Research Triangle Institute CanAllocate: Street: PO Box 12194 Street: 3040 Cornwallis Road City: Research Triangle Park State/Prov: NC Country: US PostalCode: 27709 RegDate: 1970-01-01 Updated: 2011-09-24 OrgAbuseHandle: SMU11-ARIN OrgAbuseHandle: LINDA5-ARIN OrgAdminHandle: CASAN-ARIN OrgTechHandle: ZR42-ARIN OrgTechHandle: LINDA5-ARIN OrgTechHandle: SMU11-ARIN OrgAbuseHandle: ZR42-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.