Exploring the Security Vulnerability in Frequency-Hiding Order-Preserving Encryption

Table 2

Datasets representing different levels of distinct ciphertext exposure for varying numbers of range queries on the CCS diagnosis code.

Dataset name				Exposure (%)
	400	155	156	100
	200	144	143	92
	100	113	113	72
	50	74	73	49

The total number of data points is 1894 , with 156 distinct values . represents the expected number of distinct ciphertexts after queries according to equation (4), represents the measured number of distinct ciphertexts after queries, and exposure (%) is the corresponding percentage of over the total distinct values . All values in the above table are rounded to one decimal place.