2001:1800::/32 - SWCPV6-1
V6NetHandle: NET6-2001-1800-1 OrgID: SWCP Parent: NET6-2001-1800-0 NetName: SWCPV6-1 NetRange: 2001:1800:: - 2001:1800:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF NetType: allocation RegDate: 2003-05-23 Updated: 2012-03-02 TechHandle: ZS132-ARIN Source: ARIN OrgID: SWCP OrgName: Southwest Cyberport, Inc. CanAllocate: Street: 5021 Indian School NE Street: Suite 600 City: Albuquerque State/Prov: NM Country: US PostalCode: 87110 RegDate: 1994-10-20 Updated: 2018-08-07 OrgAbuseHandle: COSTL2-ARIN OrgAdminHandle: JKC3-ARIN OrgTechHandle: MC143-ARIN OrgTechHandle: COSTL2-ARIN OrgNOCHandle: NOS19-ARIN OrgNOCHandle: ZS132-ARIN OrgAbuseHandle: NOS19-ARIN OrgNOCHandle: COSTL2-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.