IP subnet calculator IPv4 & IPng (IPv6)
transform into
IP
netmask
subnet
broadcast
host from to
#hosts #IPs

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IPv4 class A class B class C Multicast

IPv6 reserved loopback internet first addresses internet new official
IPv6 internet routing IPv6 to IPV4 multicast Link-local unicast
IPv6 Site-local unicast local IPv4 to IPv6 6bone (for backbone research)