AS20057 AT&T Mobility LLC
2600:380:4c00::/38 - ATTMOV6-1
V6NetHandle: NET6-2600-300-1 OrgID: ATTMO-3 Parent: NET6-2600-1 NetName: ATTMOV6-1 NetRange: 2600:300:: - 2600:3FF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF NetType: allocation OriginAS: 16572, 20057, 27522, 19540, 17258 RegDate: 2011-10-21 Updated: 2012-03-20 Source: ARIN OrgID: ATTMO-3 OrgName: AT&T Mobility LLC CanAllocate: Street: 16631 NE 72nd Way Street: ATTN: IP Management City: Redmond State/Prov: WA Country: US PostalCode: 98052 Comment: For policy abuse issues contact: email@example.com Comment: Send all legal requests to: Comment: ATT National Compliance Center Comment: 11760 US Hwy 1, Suite 600 Comment: North Palm Beach, FL 33408 Comment: Phone Number: 1-800-635-6840 Comment: Fax Number: 1-888-938-4715 Comment: Email: firstname.lastname@example.org RegDate: 2008-10-10 Updated: 2018-08-03 OrgTechHandle: IPADM2-ARIN OrgTechHandle: CINGU-ARIN OrgAdminHandle: MWE117-ARIN OrgAbuseHandle: CINGU-ARIN Source: ARIN POCHandle: MWE117-ARIN IsRole: N LastName: Webb FirstName: Martha Street: 16331 NE 72nd Way Street: Attn: IP Management City: Redmond State/Prov: WA Country: US PostalCode: 98052 RegDate: 2008-07-02 Updated: 2019-04-16 OfficePhone: +1-425-897-0745 Mailbox: email@example.com Source: ARIN POCHandle: CINGU-ARIN IsRole: Y LastName: Cingular DNS FirstName: Street: Ed Willams Street: 240 N Meridian St Street: Room 280 City: Indianapolis State/Prov: IN Country: US PostalCode: 46204 RegDate: 2005-02-10 Updated: 2017-06-23 OfficePhone: +1-317-265-8902 Mailbox: firstname.lastname@example.org Mailbox: email@example.com 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.