Albert and Barnabe exchange information using the RSA cryptosystem. They

wish to check their identities using the authentification procedure.

Their information is given below. Barnabe receives the ciphered signature

Your answer will be "yes" or "no" (without the inverted commas).

Albert and Barnabe exchange information using the RSA cryptosystem. They

wish to check their identities using the authentification procedure.

Their information is given below. Barnabe receives the ciphered signature

Your answer will be "yes" or "no" (without the inverted commas).

Federico wants to use the RSA cryptosystem and chooses the following data:

, , .

Is his data legitimate ?

To communicate between them, Anaïs and Bastien use an alphabet of only ten letters: 

a = 0, b = 1, c = 2, d = 3, e = 4, f = 5, g = 6, h = 7, i = 8, j = 9.

To encipher their messages, they decide to use the generalised Vigenère cipher on bigrams.

Bastien receives from Anaïs the ciphertext EGAE

Decipher the message knowing that the enciphering key is

A : 

 2  1 

 1  4 

B : 

 2 

 7 

Your answer will be a four letters word written in capital letters with no spaces.

To communicate between them, Anaïs and Bastien use an alphabet of only ten letters: 

a = 0, b = 1, c = 2, d = 3, e = 4, f = 5, g = 6, h = 7, i = 8, j = 9.

To encipher their messages, they decide to use the generalised Vigenère cipher on bigrams.

Bastien receives from Anaïs the ciphertext FEGJ

Decipher the message knowing that the enciphering key is

A : 

 3  2 

 4  3 

B : 

 4 

 8 

Your answer will be a four letters word written in capital letters with no spaces.