2620:0:c80::/48 - NCSA-UIUC
V6NetHandle: NET6-2620-C80-1 OrgID: NCSA-3 Parent: NET6-2620-1 NetName: NCSA-UIUC NetRange: 2620:0:C80:: - 2620:0:C80:FFFF:FFFF:FFFF:FFFF:FFFF NetType: assignment OriginAS: 1224 RegDate: 2008-04-14 Updated: 2012-03-02 NOCHandle: ZN5-ARIN AbuseHandle: ND63-ORG-ARIN TechHandle: ND63-ORG-ARIN Source: ARIN OrgID: NCSA-3 OrgName: National Center for Supercomputing Applications CanAllocate: Street: NCSA Street: 1205 W. Clark St City: Urbana State/Prov: IL Country: US PostalCode: 61801 RegDate: 1990-03-26 Updated: 2011-04-06 OrgTechHandle: ND63-ORG-ARIN OrgAbuseHandle: ND63-ORG-ARIN OrgAdminHandle: ND63-ORG-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.