Convert an IP address to an IP Number
IP address (IPv4 / IPv6) is divided into 4 sub-blocks. Each sub-block has a different weight number each powered by 256. IP number is being used in the database because it is efficient to search between a range of number in database.
Beginning IP number and Ending IP Number are calculated based on following formula:
IP Number = 16777216*w + 65536*x + 256*y + z (Formula 1)
where
IP Address = w.x.y.z
For example, if IP address is "202.186.13.4", then its IP Number "3401190660" is based on the Formula 1.
IP Address = 202.186.13.4
So, w = 202, x = 186, y = 13 and z = 4
IP Number = 16777216*202 + 65536*186 + 256*13 + 4
= 3388997632 + 12189696 + 3328 + 4
= 3401190660
To reverse IP number to IP address,
w = int ( IP Number / 16777216 ) % 256
x = int ( IP Number / 65536 ) % 256
y = int ( IP Number / 256 ) % 256
z = int ( IP Number ) % 256
where % is the mod operator and int is return the integer part of the division.
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