2001:4c5c::/30 - PL-AMSK-20050420
inet6num: 2001,4c58,,/29 netname: PL-AMSK-20050420 country: PL org: ORG-AMAN1-RIPE admin-c: AMSK1-RIPE tech-c: AMSK1-RIPE status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: ACI-MNT-POLAND mnt-routes: ACI-MNT-POLAND notify: firstname.lastname@example.org created: 2013-02-11T10,54,55Z last-modified: 2017-02-15T13,20,29Z source: RIPE organisation: ORG-AMAN1-RIPE org-name: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie, Akademickie Centrum Informatyki org-type: LIR address: al. Piastow 41 address: 71-065 address: Szczecin address: POLAND phone: +48914495858 fax-no: +48914494652 e-mail: email@example.com admin-c: KB470-RIPE admin-c: BU116-RIPE admin-c: SN2158-RIPE admin-c: AMSK1-RIPE admin-c: LS10590-RIPE admin-c: MB29513-RIPE mnt-ref: ACI-MNT-POLAND mnt-ref: RIPE-NCC-HM-MNT mnt-by: RIPE-NCC-HM-MNT mnt-by: ACI-MNT-POLAND abuse-c: AD10876-RIPE created: 2004-04-17T11,46,33Z last-modified: 2017-02-15T13,20,35Z source: RIPE role: Academic Centre of Computer Science org: ORG-AMAN1-RIPE address: Zachodniopomorski Uniwersytet Technologiczny w Szczecinie address: Akademickie Centrum Informatyki address: al. Piastow 41 address: 71-065 Szczecin address: POLAND remarks: Akademicka Miejska Siec Komputerowa - AMSK Szczecin phone: +48.914495858 e-mail: firstname.lastname@example.org abuse-mailbox: email@example.com admin-c: KB470-RIPE admin-c: DW391-RIPE admin-c: BU116-RIPE tech-c: SN2158-RIPE tech-c: LS10590-RIPE tech-c: SK2474-RIPE nic-hdl: AMSK1-RIPE mnt-by: ACI-MNT-POLAND created: 2003-03-24T11,10,11Z last-modified: 2013-04-04T11,15,43Z source: RIPE
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.