Reversible Fragile Watermarking Scheme for Relational Database Based on Prediction-Error Expansion

Table 1

Notations and parameters.

Symbol	Description
Η	Number of tuples in the relation
Γ	Number of attributes in the relation
ti·Aj	j^th attribute of the i^th tuple
ti·Pk	Primary key of the i^th tuple
hi	Hash value of the i^th tuple’s primary key
Hj	Hash value of the j^th attribute
Ks	Secret key
V	Number of groups
µ	Average number of tuples in a group
Gj	j^th group
E	Prediction error
	Expanded prediction error
Wj	Watermark embedded in attribute Aj