AES (Advanced Encryption Standard) and ECC (Elliptic Curve Cryptography) are both cryptographic algorithms used for securing data, but they operate in different ways and serve different purposes:
AES (Advanced Encryption Standard)
- AES is a symmetric encryption algorithm, meaning the same key is used for both encryption and decryption.
- It operates on blocks of data and is commonly used for encrypting large amounts of data, such as files or entire hard drives.
- AES is widely adopted and considered secure when used with sufficiently long keys (128, 192, or 256 bits).
- Code Size: The code size for implementing AES depends on factors such as the programming language, optimization techniques used, and the desired features (e.g., support for different key lengths).
- In optimized implementations, the core AES algorithm (encryption and decryption) can be relatively compact. Implementations in low-level languages like C or assembly language are often more efficient in terms of code size.
- Additional features such as key expansion, mode of operation (e.g., CBC, ECB), and padding schemes can increase the overall code size.
- Memory Footprint: The memory footprint of AES implementations can vary depending on factors such as the key length, block size, and the specific operations being performed.
- Memory requirements typically include space for storing the encryption/decryption keys, the input plaintext/ciphertext blocks, and intermediate values during computation.
- For embedded systems or devices with limited resources, memory optimization techniques such as minimizing the number of lookup tables or precomputing values can be employed to reduce memory usage
ECC (Elliptic Curve Cryptography)
- ECC is an asymmetric encryption algorithm, meaning it uses a pair of keys: a public key used on one end and a private key used on the other. For example, in signing, the encryption is done with the private key and verification is done with the public key.
- It is based on the mathematics of elliptic curves over finite fields.
- ECC is particularly well-suited for scenarios where computational resources are limited, such as mobile devices or IoT devices, as it offers equivalent security to RSA but with shorter key lengths, resulting in faster computations and less memory usage. That being said, ECC requires larger keys than AES to provide equivalent encryption strength.
- ECC is often used for key exchange protocols like Diffie-Hellman key exchange and in digital signatures.
- Code Size: Implementing ECC requires additional mathematical operations compared to AES, particularly involving elliptic curve arithmetic. However, optimized libraries are available that provide efficient ECC implementations.
- Code size can vary depending on factors such as the choice of elliptic curve parameters, the underlying arithmetic field, and the desired level of optimization.
- Libraries such as WolfSSL or OpenSSL provide ECC functionality and can be integrated into applications with relatively modest code size overhead.
- Memory Footprint: ECC implementations typically require memory for storing various parameters, including public/private keys, intermediate values during computation, and precomputed tables for performance optimization.
- Memory usage depends on factors such as the key size, the chosen elliptic curve, and the specific operations being performed (e.g., key generation, point multiplication).
- ECC implementations optimized for memory-constrained environments often utilize techniques such as point compression to reduce memory usage.
In summary, AES is used for symmetric encryption of large amounts of data, while ECC is used for signing/verification and key exchange, particularly in resource constrained environments.
If you have questions about any of the above, please contact us at facts@wolfSSL.com or call us at +1 425 245 8247.
Download wolfSSL Now