103.21.198.0/24

inetnum:        103.21.196.0 - 103.21.199.255
netname:        LETSWIN2012-NET
descr:          LETSWIN Technology Co.,LTD
descr:          1F., No.54, Anping Rd., Zhonghe Dist.
descr:          New Taipei City 235, Taiwan (R.O.C.)
country:        TW
admin-c:        CY2120-AP
tech-c:         CY2120-AP
status:         ALLOCATED PORTABLE
mnt-by:         MAINT-TW-TWNIC
mnt-lower:      MAINT-TW-TWNIC
mnt-routes:     MAINT-TW-TWNIC
mnt-irt:        IRT-TWNIC-AP
changed:        hm-changed@apnic.net 20121017
source:         APNIC

irt:            IRT-TWNIC-AP
address:        Taipei, Taiwan, 100
e-mail:         hostmaster@twnic.net.tw
abuse-mailbox:  hostmaster@twnic.net.tw
admin-c:        TWA2-AP
tech-c:         TWA2-AP
auth:           # Filtered
remarks:        Please note that TWNIC is not an ISP and is not empowered
remarks:        to investigate complaints of network abuse.
mnt-by:         MAINT-TW-TWNIC
changed:        hostmaster@twnic.net.tw 20101108
source:         APNIC

person:         CHENGPAO Yang
nic-hdl:        CY2120-AP
e-mail:         letwin_886@hotmail.com
address:        LETSWIN Technology Co.,LTD
address:        1F., No.54, Anping Rd., Zhonghe Dist.
address:        New Taipei, Taiwan
phone:          +886-2-29481118
fax-no:         +886-2-29481118
country:        tw
changed:        hostmaster@twnic.net.tw 20121016
mnt-by:         MAINT-TW-TWNIC
source:         APNIC

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.