188.239.0.0/18

inetnum:        188.239.0.0 - 188.239.63.255
netname:        NASHNET5-NET
country:        UA
org:            ORG-NL150-RIPE
admin-c:        DUMY-RIPE
tech-c:         DUMY-RIPE
status:         ASSIGNED PI
mnt-by:         RIPE-NCC-END-MNT
mnt-by:         SANYA-MNT
mnt-by:         NASHNET-MNT
mnt-routes:     NASHNET-MNT
mnt-domains:    NASHNET-MNT
created:        2011-02-07T15:59:44Z
last-modified:  2017-03-30T12:17:03Z
source:         RIPE
sponsoring-org: ORG-CL126-RIPE
remarks:        ****************************
remarks:        * THIS OBJECT IS MODIFIED
remarks:        * Please note that all data that is generally regarded as personal
remarks:        * data has been removed from this object.
remarks:        * To view the original object, please query the RIPE Database at:
remarks:        * http://www.ripe.net/whois
remarks:        ****************************


organisation:   ORG-NL150-RIPE
org-name:       NASHNET LTD
org-type:       other
address:        Dummy address for ORG-NL150-RIPE
e-mail:         unread@ripe.net
abuse-c:        NASH-RIPE
mnt-ref:        SANYA-MNT
mnt-by:         SANYA-MNT
mnt-by:         NASHNET-MNT
created:        2011-01-25T12:18:31Z
last-modified:  2017-10-30T14:47:00Z
source:         RIPE
remarks:        ****************************
remarks:        * THIS OBJECT IS MODIFIED
remarks:        * Please note that all data that is generally regarded as personal
remarks:        * data has been removed from this object.
remarks:        * To view the original object, please query the RIPE Database at:
remarks:        * http://www.ripe.net/whois
remarks:        ****************************

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.