#IPv4 TCP/IP v4 address - e.g. `192.168.0.1`
## References
[IP - Wikipedia](https://en.wikipedia.org/wiki/Internet_protocol_suite)
[IPa - Wikipedia](https://en.wikipedia.org/wiki/IP_address)
[IPv4 - Wikipedia](https://en.wikipedia.org/wiki/Internet_Protocol_version_4)
[IPv4 subnet calculator](https://www.adminsub.net/ipv4-subnet-calculator)
## Address Space
x = 0, 1, 2, .... 253, 254, 255
In an IPv4 range the first address is reserved to denote the network address (e.g. 192.168.0.0/24), while the last is reserved for the broadcast address (e.g. 192.168.0.255/24).
IPv4/CIDR | # of addresses | usable address range | broadcast address
----|----|----|----
192.168.0.1/32 | 2³²-2³² = 2⁰ = **1**|192.168.0.x - 192.168.0.x|192.168.0.x
192.168.0.1/31 | 2³²-2³¹ = 2¹ = **2**|192.168.0.1 - 192.168.0.1|192.168.0.1
192.168.0.1/30 | 2³²-2³⁰ = 2² = **4**|192.168.0.1 - 192.168.0.2|192.168.0.3
192.168.0.1/29 | 2³²-2²⁹ = 2³ = **8**|192.168.0.1 - 192.168.0.6|192.168.0.7
192.168.0.1/28 | 2³²-2²⁸ = 2⁴ = **16**|192.168.0.1 - 192.168.0.14|192.168.0.15
192.168.0.1/27 | 2³²-2²⁷ = 2⁵ = **32**|192.168.0.1 - 192.168.0.30|192.168.0.31
192.168.0.1/26 | 2³²-2²⁶ = 2⁶ = **64**|192.168.0.1 - 192.168.0.62|192.168.0.63
192.168.0.1/25 | 2³²-2²⁵ = 2⁷ = **128**|192.168.0.1 - 192.168.0.126|192.168.0.127
192.168.0.1/24 | 2³²-2²⁴ = 2⁸ = **256**|192.168.0.1 - 192.168.0.254|192.168.0.255
192.168.0.1/23 | 2³²-2²³ = 2⁹ = **512**|192.168.0.1 - 192.168.1.254|192.168.1.255
192.168.0.1/22 | 2³²-2²² = 2¹⁰ = **1024**|192.168.0.1 - 192.168.3.254|192.168.3.255
192.168.0.1/21 | 2³²-2²¹ = 2¹¹ = **2048**|192.168.0.1 - 192.168.7.254|192.168.7.255
192.168.0.1/20 | 2³²-2²⁰ = 2¹² = **4096**|192.168.0.1 - 192.168.15.254|192.168.15.255
192.168.0.1/19 | 2³²-2¹⁹ = 2¹³ = **8192**|192.168.0.1 - 192.168.31.254|192.168.31.255
192.168.0.1/18 | 2³²-2¹⁹ = 2¹³ = **16384**|192.168.0.1 - 192.168.63.254|192.168.63.255
192.168.0.1/17 | 2³²-2¹⁹ = 2¹³ = **32768**|192.168.0.1 - 192.168.127.254|192.168.127.255
192.168.0.1/16 | 2³²-2¹⁹ = 2¹³ = **65536**|192.168.0.1 - 192.168.255.254|192.168.255.255