2620:72::/48 - ESC-CIDR6-1
V6NetHandle: NET6-2620-72-1 OrgID: ESC-103 Parent: NET6-2620-1 NetName: ESC-CIDR6-1 NetRange: 2620:72:: - 2620:72:0:FFFF:FFFF:FFFF:FFFF:FFFF NetType: assignment OriginAS: 4181, 16842, 10359 RegDate: 2010-08-24 Updated: 2012-03-02 AbuseHandle: HOSTM1543-ARIN NOCHandle: HOSTM1543-ARIN TechHandle: HOSTM1543-ARIN Source: ARIN OrgID: ESC-103 OrgName: Epic Systems Corporation CanAllocate: Street: 1979 Milky Way City: Verona State/Prov: WI Country: US PostalCode: 53593 RegDate: 2006-12-18 Updated: 2011-09-24 OrgAbuseHandle: HOSTM1543-ARIN OrgAdminHandle: HOSTM1543-ARIN OrgTechHandle: HOSTM1543-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.