Question

7. The cryptogram UIF RVJDL CSPXO GPY KVNQT PWFS UIF HBUF was obtained by enciphering THE QUICK BROWN FOX JUMPS OVER THE GATE using a Simple Substitution Cipher. How much of the key is determined by the information given? How many possible keys are there?

Answer 1

The cryptogram UIF RVJDL CSPXO GPY KVNQT PWFS UIF HBUF was obtained by enciphering THE QUICK BROWN FOX JUMPS OVER THE GATE using a Simple Substitution Cipher. How much of the key is determined by the information given? How many possible keys are there?

Plain Text: THE QUICK BROWN FOX JUMPS OVER THE GATE

Cipher Text: UIF RVJDL CSPXO GPY KVNQT PWFS UIF HBUF

Let us see in the Detail:

A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z
1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26

if K=1

B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U	V	W	X	Y	Z	A
1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26

Cipher Text = (Plain Text+Key)%26 By using the Substitution

Plain Text: THE QUICK BROWN FOX JUMPS OVER THE GATE

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CIPHER TEXT:(Encrypted Text)

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UIF RVJDL CSPXO GPY KVNQT PWFS UIF HBUF

How much of the key is determined by the information given?

Answer: Key =1

How many possible keys are there?

There are 26 possible keys are available in the substitution cipher.