An Approach Based on Customized Robust Cloaked Region for Geographic Location Information Privacy Protection

Algorithm 3

Integrated robust cloaked region (RCR) generation algorithm.

	Definition: cl = the bottom left cell of the RCR,
	cr = the upper right cell of the RCR,
	M = (cl, cr) (a rectangle determined by cl and cr),
	Ccenter = the cell in which the targeted user is located,
	maxUserDensity = the maximum value of userDensity
	Input: Nearby users’ cloaked regions, customized size constraints Amin and Amax, location semantic K under time T
	Output: the RCR for the target user
(1)	Update userMap with location semantics K;
(2)	Assign the calculated P () for each cell in the userMap;
(3)	for each rectangle M = (i, j) in the userMap do
(4)	if M contains Ccenter, and S (M) < Amax, S (M) > Amin then
(5)	calculate userDensity (M);
(6)	if userDensity (M) > maxUserDensity then
(7)	maxUserDensity = userDensity (M); cl = i; cr = j;
(8)	end
(9)	end
(10)	end
(11)	return RCR determined by cr and cl