What does $\Pi$ represent in cryptography?

Question

I am doing a project in cryptography and while reading a tag generation algorithm for files, I got stuck with the meaning of $\Pi$. The screenshot of the algorithm is inserted below.

Fig

Here the KeyGen algorithm generates 1 public key and 2 secret keys and the TagGen algorithm takes a file $M$ (which is divided into $n$ blocks which is again divided into $s$ sectors) and the secret keys generated by the KeyGen algorithm. TagGen has to compute tags for blocks of the file $M$. I am stuck with how the data tags are computed here.

score 14 · Accepted Answer · edited Nov 18 '14 at 09:23

14

This is standard mathematical notation and not specific to cryptography. The $\Pi$ symbol means Product in much the same sense $\Sigma$ means Sum. For instance, $$\prod_{i=0}^2{u_i^{m_i}} = u_0^{m_0}u_1^{m_1}u_2^{m_2}$$

edited Nov 18 '14 at 09:23

fgrieu

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answered Jan 26 '14 at 16:21

Henrick Hellström

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score 1 · Answer 2 · answered Nov 18 '14 at 21:57

1

It's the notation for the Encryption scheme in use, consisting key generation, decryption and encryption algorithms. Open form: Π = (Gen,Enc,Dec)

answered Nov 18 '14 at 21:57

Ugur

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What does $\Pi$ represent in cryptography?

2 Answers2