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Ella Rose
Ella Rose
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As mentioned in the comments, it appears that you are seeking to understand what provides a cipher with resistance to known plaintext attack. "Diffusion" and "Confusion""Diffusion" and "Confusion" I think are the answer here.

Diffusion

"Diffusion" means that the terms/bits of the algebraic expression of the cipher are inter-dependent. Without diffusion, different subsections of the state will act independently, and so can be attacked independently. With diffusion, different subsections of the state will be dependent on the values of other subsections of the state. More diffusion leads to a greater number of terms in the expressions that represent the cipher.

Confusion

"Confusion" means that the algebraic expressions of the cipher are non-linear, which makes them difficult to work with. Non-linearity increases the degree of the ciphers equations. Ideally, the non-linear expressions are not even approximately similar to any linear expressions.

A linear cipher can often times be easily broken with negligible time/space complexity, regardless of how many rounds or how much key material is applied. The linearity means that we can view the ciphertext as a simple equation of key + message bits, which can be easily solved if you know the message bits.

As mentioned in the comments, it appears that you are seeking to understand what provides a cipher with resistance to known plaintext attack. "Diffusion" and "Confusion" I think are the answer here.

Diffusion

"Diffusion" means that the terms/bits of the algebraic expression of the cipher are inter-dependent. Without diffusion, different subsections of the state will act independently, and so can be attacked independently. With diffusion, different subsections of the state will be dependent on the values of other subsections of the state. More diffusion leads to a greater number of terms in the expressions that represent the cipher.

Confusion

"Confusion" means that the algebraic expressions of the cipher are non-linear, which makes them difficult to work with. Non-linearity increases the degree of the ciphers equations. Ideally, the non-linear expressions are not even approximately similar to any linear expressions.

A linear cipher can often times be easily broken with negligible time/space complexity, regardless of how many rounds or how much key material is applied. The linearity means that we can view the ciphertext as a simple equation of key + message bits, which can be easily solved if you know the message bits.

As mentioned in the comments, it appears that you are seeking to understand what provides a cipher with resistance to known plaintext attack. "Diffusion" and "Confusion" I think are the answer here.

Diffusion

"Diffusion" means that the terms/bits of the algebraic expression of the cipher are inter-dependent. Without diffusion, different subsections of the state will act independently, and so can be attacked independently. With diffusion, different subsections of the state will be dependent on the values of other subsections of the state. More diffusion leads to a greater number of terms in the expressions that represent the cipher.

Confusion

"Confusion" means that the algebraic expressions of the cipher are non-linear, which makes them difficult to work with. Non-linearity increases the degree of the ciphers equations. Ideally, the non-linear expressions are not even approximately similar to any linear expressions.

A linear cipher can often times be easily broken with negligible time/space complexity, regardless of how many rounds or how much key material is applied. The linearity means that we can view the ciphertext as a simple equation of key + message bits, which can be easily solved if you know the message bits.

Source Link
Ella Rose
Ella Rose
  • 19.9k
  • 6
  • 55
  • 103

As mentioned in the comments, it appears that you are seeking to understand what provides a cipher with resistance to known plaintext attack. "Diffusion" and "Confusion" I think are the answer here.

Diffusion

"Diffusion" means that the terms/bits of the algebraic expression of the cipher are inter-dependent. Without diffusion, different subsections of the state will act independently, and so can be attacked independently. With diffusion, different subsections of the state will be dependent on the values of other subsections of the state. More diffusion leads to a greater number of terms in the expressions that represent the cipher.

Confusion

"Confusion" means that the algebraic expressions of the cipher are non-linear, which makes them difficult to work with. Non-linearity increases the degree of the ciphers equations. Ideally, the non-linear expressions are not even approximately similar to any linear expressions.

A linear cipher can often times be easily broken with negligible time/space complexity, regardless of how many rounds or how much key material is applied. The linearity means that we can view the ciphertext as a simple equation of key + message bits, which can be easily solved if you know the message bits.