| mask == 32 = IPv4Address oct1 oct2 oct3 oct4
| mask == 31 = IPv4Address oct1 oct2 oct3 (Octet a25 a26 a27 a28 a29 a30 a31 Zero)
| mask == 30 = IPv4Address oct1 oct2 oct3 (Octet a25 a26 a27 a28 a29 a30 Zero Zero)
| mask == 32 = IPv4Address oct1 oct2 oct3 oct4
| mask == 31 = IPv4Address oct1 oct2 oct3 (Octet a25 a26 a27 a28 a29 a30 a31 Zero)
| mask == 30 = IPv4Address oct1 oct2 oct3 (Octet a25 a26 a27 a28 a29 a30 Zero Zero)