Question

Computer Science Encryption. Please make it simple only a few sentences should suffice just not too long thank you

2. Explain why it is impractical to use an ideal block cipher for real-world encryption.

Answer 1

To make it simple, and precise :

It is the encryption key that makes the ideal block cipher impractical for use in real world. For a plaintext bolo of 64 bits we need a key of size : 64*2^64 , equivalent to 10^21 bits which is very large for practical purposes.

If we make the size of block small then it will become susceptible to attacks. So in both ways it is not practical to use .

Hope this helps