# size of group points and parameters in pairing based cryptography

$$e:G_1\times G_1\rightarrow G_2$$ In symmetric pairing-based cryptography with groups$(G_1,G_2)$ of prime order $q$ and $a,b \in Z_q$
Will the size of random generator $P$ from$G_1$ and $a$ be same? I think it is different. I don't know why.

• What are $a$ and $b$? – fkraiem Oct 11 '16 at 9:36
• @fkraiem.$a,b$ selected from $Z_q$ – myat Oct 11 '16 at 9:39
• Yes, I can see that much, but what are they for? – fkraiem Oct 11 '16 at 11:40
• @fkraiem. They are for pairing-based cryptography. – myat Oct 12 '16 at 4:46