Elliptic Curve Integrated Encryption Scheme, or ECIES, is a hybrid encryption system proposed by Victor Shoup in 2001
Elliptic Curve Integrated Encryption Scheme, or ECIES, is a hybrid encryption system proposed by Victor Shoup in 2001. ECIES has been standardized in ANSI X9.63, IEEE 1363a, ISO/IEC 18033-2, and SECG SEC-1. Shoup's submission can be found at http://www.shoup.net/papers/iso-2_1.pdf.
ECIES combines a Key Encapsulation Mechanism (KEM) with a Data Encapsulation Mechanism (DEM). The system independently derives a bulk encryption key and a MAC key from a common secret. Data is first encrypted under a symmetric cipher, and then the cipher text is MAC'd under an authentication scheme. Finally, the common secret is encrypted under the public part of a public/private key pair.
The output of the encryption function is the tuple {K,C,T}, where K is the encrypted common secret, C is the ciphertext, and T is the authentication tag. There is some hand waiving around the "common secret" since its actually the result of applying a Key Agreement function, and it uses the recipient's static public key and an ephemeral key pair.
A closely related system is Discrete Logarithm Integrated Encryption Scheme (DLIES), proposed by Abdalla, Bellare and Rogaway, which operates over integers rather than elliptic curves.
