inetnum: 2804:15f8::/32 aut-num: AS11338 abuse-c: SBLGB owner: SKY SERVIÇOS DE BANDA LARGA LTDA ownerid: 000.497.373/0001-10 responsible: Infra-estrutura de Redes country: BR owner-c: SBLGB tech-c: GRIAC2 created: 20140408 changed: 20160614 nic-hdl-br: GRIAC2 person: Grupo de Redes IP da ACOM e-mail: firstname.lastname@example.org created: 20100818 changed: 20140114 nic-hdl-br: SBLGB person: Sky Banda Larga - Gerencia Backbone e-mail: email@example.com created: 20160624 changed: 20160624
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.