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Ella Rose
Ella Rose
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Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs. I'm sure if you wanted you could come up with/find an example of an ARX Feistel network or build an SP network from ARX instructions, but I'm not sure what advantages it would offer.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandompseudorandom permutation", and the psuedorandompseudorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandompseudorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandompseudorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily trueThe presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs. I'm sure if you wanted you could come up with/find an example of an ARX Feistel network or build an SP network from ARX instructions, but I'm not sure what advantages it would offer.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandom permutation", and the psuedorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs. I'm sure if you wanted you could come up with/find an example of an ARX Feistel network or build an SP network from ARX instructions, but I'm not sure what advantages it would offer.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "pseudorandom permutation", and the pseudorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the pseudorandom permutation.

A more recent cipher construction that can be built from an arbitrary pseudorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

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

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time executionconstant time execution as well as to facilitate efficient SIMD implementationsSIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel NetworksFeistel Networks generally aren't present in ARX designs. I'm sure if you wanted you could come up with/find an example of an ARX Feistel network or build an SP network from ARX instructions, but I'm not sure what advantages it would offer.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandom permutation""psueodrandom permutation", and the psuedorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour constructionEven-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandom permutation is the sponge construction. Technically the duplex constructionduplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandom permutation", and the psuedorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs. I'm sure if you wanted you could come up with/find an example of an ARX Feistel network or build an SP network from ARX instructions, but I'm not sure what advantages it would offer.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandom permutation", and the psuedorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).

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

Are ARX block ciphers considered there own class of block cipher separate from SPNs and Feistel-like ones?

Generally speaking, yes. ARX ciphers typically only use simple CPU instructions (Addition, Rotation, and Xor) and are typically designed to ensure constant time execution as well as to facilitate efficient SIMD implementations.

The s-boxes and split state that are so prevalent among SPN and Feistel Networks generally aren't present in ARX designs.

Are there other schemes out there besides Feistel-like designs, SPNs, and ARX? Or is there really nothing new under the sun?

Typically, the ARX/SPN/Feistel part of the algorithm is used to create a "psueodrandom permutation", and the psuedorandom permutation is then used as part of a cipher construction to provide encryption.

The basic cipher construction is the iterated key or Even-Mansour construction. AES can be modeled like this, as an interleaved application of a key addition layer with the psuedorandom permutation.

A more recent cipher construction that can be built from an arbitrary psuedorandom permutation is the sponge construction. Technically the duplex construction is a stream cipher, rather then a block cipher. I think that this is actually a key point: The presumption that a block cipher is the best way to encrypt is not necessarily true.

Permutation based

Permutation based constructions are usually more versatile, and often times offer an all-in-one solution (authenticated encryption, hashing, MACs); While you could construct all of the above via a block cipher, it is much more straightforward from an implementation perspective to use a permutation based construction like the sponge construction.

Homomorphic Ciphers

There exist "linear" secret key ciphers, like this one from Fully Homomorphic Encryption Over The Integers. Typically these sorts of ciphers are designed to facilitate homomorphic encryption and/or to instantiate public key cryptosystems. They are often times built from number-theoretic perspectives, and clearly do not resemble any of the other cipher categories (and you would not use them for the same reasons).