Aes

Advanced Encryption Standard (AES) is a cryptographic block cipher algorithm.

Rsa

RSA is a common public key algorithm, which can be used for encryption and signature



Possible performance first

Example

"Note that it s also possible to create aes keys that require authentication when decrypting but not when encrypting which is rather cool aes is much much faster than rsa"

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How do I require user authentication only for decryption but not encryption

"There are two reasons for that performance aes is faster then rsa and resources aes is less resource hungry than rsa"

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IOS MDM profile signing, which certificate to use?

"And regarding your first question it is definitely possible to encrypt decrypt messages directly using rsa there are only technical and performance reasons aes is much faster than rsa why rsa is used only to encrypt a session key and aes is used to encrypt decrypt the messages themselves"

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Encrypted communication C# <-> PHP using RSA and AES

Slower data sizes

Example

"Rsa is much slower than aes"

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Encrypting / Decrypting Lists of data efficiently

"Execution of aes is more faster than rsa for same key sizes"

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RSA Encryption-Decryption of AES key and storing in file

"The aes key is encrypting much more data but is much faster than rsa encryption"

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Openssl smime: aes vs rsa - which one encrypts?

"So the 115 seconds will be reduced to 3-4 secs plus the encryption decryption time used for aes which is much faster than rsa"

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RSA encryption results in server execution timeout

"You should be encrypting your data with a symmetric key like aes then encrypting the symmetric key with rsa;rsa should not be used to encrypt this kind of data"

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RSA Encryption and Decryption in C#.NET

"One of the reasons to do so is that rsa is much slower than for example aes"

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Manual implementation RSA java. Padding ideas

"Like you heard asymmetric cryptography like rsa is much slower than symmetric cryptography aes but it does have it s advantages simpler key management a single private key to protect"

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Encrypting/Decrypting large files (.NET)

"It shows that rsa encrypt is faster then aes encrypt"

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AES faster than RSA Encryption?

"I will also note that encrypting with rsa is much much slower than encrypting with a symmetric algorithm such as aes"

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Double encrypting 2048 RSA?

"Since aes is much faster than rsa and aes is much shorter than the actual message"

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Spring saml: why in saml response, key info could be encrypted?

"In general asymmetric encryption such as rsa is not used to encrypt data data is in general encrypted with symmetric encryption such as aes.the choice usually boils down to the need for separate encryption and decryption keys and or pki;both are as secure at comparable key sizes and aes is much faster"

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RSA encrypt file or text

Secure

Example

"Asymmetric key encryption ex rsa is no more secure than symmetric key encryption ex aes"

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How the RSA algorithm (encryption and decryption) works in real life?

"Asymmetric encryption ex rsa is no more secure than symmetric encryption ex aes"

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Understanding Encryption in Realm

"How is aes less secure than rsa in this scenario"

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Sending username and password between domains securely

Others

Example

Note however that doing so means that each encrypted chunk has each encrypted chunk own padding and that rsa is much more computationally expensive than aes

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Encrypt a long text string using RSA encryption only

As far as efficiency rsa is going to be orders of magnitudes slower than aes so the trade-off you make is that you give up simplicity you give up the simplicity of using aes in favor of some rsa chunking in return for poor performance you get the slower performance of rsa.

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Encrypt a long text string using RSA encryption only

Block crypto algorithms like aes do suffer from this problem too but without a pki aes is no less safe than rsa

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What is the performance difference of pki to symmetric encryption?

The whole purpose of using aes to secure the communication or any symmetric key encryption is that it s a lot faster than rsa or any public key encryption

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Handling digital signature in network applications

You could for example generate a random aes key encrypt it using rsa and store it in the output file and then encrypt the file itself with aes which is much faster and doesn t have any problem with large inputs

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Encrypting and decryption large file using rsa in java

In your particular case an rsa key of 2048 bits has a lot less strenght than an aes key of 256 bits

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InvalidKeyException for encryption but not for decryption

Considering most rsa moduli are at least 1024 bit this will be much larger than an aes key

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OpenSSL decrypt error - Padding versus Raw

If the message you re encrypting is large enough not only will the message you re encrypting is large enough take more time to process but the rsa encrypted message might be larger than an rsa encrypted aes key plus an aes encrypted message

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Encrypt a long text string using RSA encryption only

But if you use public key encryption to encrypt messages you are a limited to small messages -- a 1024 bit rsa key encrypts less than 128 bytes and b going to pay in performance because public key encryption is much more costly than symmetric key encryption such as aes encryption

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Securing A Chat Application

Rsa is an asymmetric encryption method that encrypts a number less than the modulus of the rsa key 255 bytes would indicate that you re using a 256 8 2048 bit rsa key modulus;what you need to do to encrypt values greater than that is to generate a key encrypt the data using a symmetric cipher aes is not a bad choice and encrypt the aes key using your private rsa key preferably along with some other random data

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Why does Bouncy Castle RSAEngine.processblock method always returns 255 bytes when decrypting?

I want to encrypt and store a token which is longer than what rsa permits but i can t use aes because if i want to secure it with biometrics then i have to ask for user authentication even when i am encrypting the value and not only when decrypting it as with rsa

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Android encryption framework for encrypting large strings with user authentication only when decrypting

That is actually not the case with rsa which is --- more so than aes --- just a math equation

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What is the performance difference of pki to symmetric encryption?

While 256-bit aes might sound less secure than 4096-bit rsa they might actually be quite similar from the offered protection

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SSL showing 128bit encryption for 2048 bit private key

Algorithms like rsa are much less user-friendly than aes

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What is the performance difference of pki to symmetric encryption?

If you re looking for privacy rsa isn t the way to go use rsa to generate a private public pair and then use them to excahnge keys -- or exchange keys out of band;use a streaming algorithm like aes to encrypt the message

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How to encrypt and decrypt a message by using RSA with signature in android

Rsa is not intended for bulk data encryption;instead use a symmetric cipher like aes to encrypt your large string

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Encrypt and decrypt large string in java using RSA

Rsa is not a substitute for aes;aes is a symmetric cipher that can quickly encrypt and decrypt large messages

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How to change AES cipher to RSA

Rsa is not a replacement of aes nor the other way;aes is a symmetrical algorithm and rsa is any asymmetric one

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Comparing AES vs RSA with openssl speed?

A rsa key as its name says is for rsa not for aes;aes uses a symmetric key namely an array of arbitrary bytes of length 16 24 or 32 bytes

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AES code throwing NoSuchPaddingException: Padding NoPaddin unknown

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