A Proposed Harmony Search Algorithm for Honeyword Generation

Algorithm 2

The proposed harmony search algorithm.

	Parameter
	n pitches size (population-size), HS harmony size (number of pitches that made harmony), HM harmony memory, HMS harmony memory size (equal to the max-generation), HMCR harmony memory considering rate, PAR pitch adjusting rate, bw distance bandwidth (the maximum pitch adjustment change), ap number of generated adjacent pitches, Mg max-generation, Ec evaluation criteria, d number of the generated digits tokens, dl number of digits that changed in the generated token, s number of the generated special characters tokens, sl number of special characters that changed in the generated token.
	Begin
	Tokenization/ ^∗ parse the sugarword to the alphabet of, numbers, and special characters token  ^∗ /
	If the token is an alphabet
	Generate the initial pitches population with n randomly
	Compute the fitness of the population with considering to Ec
	for i = 1 to Mg
	for j = 1 to n
	Generate rand1 in range (0, 1) and HMCR random in range (0, 1)
	if rand < HMCR
	let a pitch selected form the population randomly
	Generate rand2 in range (0, 1) and PAR random in range (0, 1)
	if rand < PAR
	Generate adjacent pitches with ap respect to bw and choose the best adjacent as the pitch
	end if
	else generate pitch randomly
	end if
	end for
	Compute the fitness of the new population with considering to Ec
	Drop the worst pitches of the population generate ones randomly
	Select the best pitches with HS as the harmony then save in HM
	end for
	Return the best harmony in HM as the alphabet honeyword tokens
	end if
	If the token is a digit
	for i = 1 to d
	for j = 1 to dl
	Changes the digits of the token by other digits randomly
	end for
	end for
	Return the d tokens as the digits honeyword tokens
	end if
	If the token is a special character
	for i = 1 to s
	for j = 1 to sl
	Changes the special characters of the token by other special characters randomly
	end for
	end for
	Return the s tokens as the special characters honeyword tokens
	end if
	Collect honeyword tokens
	Provide sweetwords by adding sugarword to honeywords then permutate and hashed the sweetwords
	End