Table 1. Key-space of the proposed scheme and some of the other methods in the literature
Method
Key space
Proposed algorithm
2
384
Ref.[
1
]
Not specified
Ref.[
2
]
2
349
Ref.[
3
]
2
400
Ref.[
4
]
2
128
Ref.[
5
]
2
135
Ref.[
6
]
2
216
Ref.[
7
]
10
56
Ref.[
8
]
2
128