I'm somewhat new to encryption. I see that the actual RSA sizes are 1024 and 2048? Can those key sizes support data blocks of 128 MB?

  • 6
    $\begingroup$ Public-key encryption of large data is routinely performed using hybrid encryption. $\endgroup$ – fgrieu Jan 30 '19 at 10:24
  • $\begingroup$ 1024 is considered too small nowadays, 2048 barely meets requirements as it has a comparable key strength of 112 bits (triple DES instead of AES). RSA works for any key size although only > 512 bit with 8 bit increments are usually supported. One RSA operation always adds padding overhead, see here how much you can encrypt at a time (note the comment below). Besides requiring more computing resources, repeated secure RSA encryption - which can be secure - also greatly expands the ciphertext size compared to the plaintext size. $\endgroup$ – Maarten Bodewes Jan 30 '19 at 14:57
  • 1
    $\begingroup$ Note that I think the title and minimal question in the body is much better than the one of the duplicate. I'll try and keep the question around for that reason - so Google can find it. Guys, please use a minimum of downvotes - finding questions / answers can be tricky. $\endgroup$ – Maarten Bodewes Jan 30 '19 at 14:59

Browse other questions tagged or ask your own question.