I've always liked storing IP's as binary(4) - still 4 bytes, but simpler conversions:

DECLARE @IpBin binary(4)

DECLARE @IpString varchar(15)

SET @IpString = '101.202.33.44'

--convert string to binary

SET @IpBin =CONVERT(binary(1), CONVERT(tinyint, PARSENAME(@IpString, 4)))

+ CONVERT(binary(1), CONVERT(tinyint, PARSENAME(@IpString, 3)))

+ CONVERT(binary(1), CONVERT(tinyint, PARSENAME(@IpString, 2)))

+ CONVERT(binary(1), CONVERT(tinyint, PARSENAME(@IpString, 1)))

SELECT @IpBin

--convert binary to string

SELECT

CAST(CAST(SUBSTRING(@IpBin,1,1) AS tinyint) AS varchar(3)) + '.' +

CAST(CAST(SUBSTRING(@IpBin,2,1) AS tinyint) AS varchar(3)) + '.' +

CAST(CAST(SUBSTRING(@IpBin,3,1) AS tinyint) AS varchar(3)) + '.' +

CAST(CAST(SUBSTRING(@IpBin,4,1) AS tinyint) AS varchar(3))