2801:80:a80::/44 - ETM4
inetnum: 2801:80:a80::/44 aut-num: AS11242 abuse-c: SIRTE8 owner: Universidade Federal de Santa Catarina ownerid: 83.899.526/0001-82 responsible: Edison Tadeu Lopes Melo owner-c: ETM tech-c: ETM inetrev: 2801:80:a80::/44 nserver: ns.pop-sc.rnp.br nsstat: 20170307 AA nslastaa: 20170307 nserver: adns1.pop-sc.rnp.br nsstat: 20170307 AA nslastaa: 20170307 nserver: adns2.pop-sc.rnp.br nsstat: 20170307 AA nslastaa: 20170307 created: 20140527 changed: 20140527 nic-hdl-br: ETM person: Edison Tadeu Lopes Melo created: 19971218 changed: 20120229 nic-hdl-br: SIRTE8 person: Security Incident Response Team created: 20160825 changed: 20160825
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.