Edit

Diffie-Hellman/Schannel Provider Algorithms

  • Article

The purpose of the Diffie-Hellman algorithm is to make it possible for two or more hosts to create and share an identical, secret encryption key, by simply sharing information over a network that is not secure. The information that gets shared over the network is in the form of a couple of constant values, and a D-H public key.

The Microsoft Diffie-Hellman/Schannel Cryptographic Provider supports the following algorithms.

Algorithm ID Description Comments
CALG_DH_SF Diffie-Hellman store and forward key exchange algorithm Key length: Can be set, 384 bits to 512 bits in 8 bit increments. Default key length: 512 bits.
CALG_MD5 MD5 hashing algorithm. Provided only for hashing.
CALG_DH_EPHEM Ephemeral D-H key exchange. Key length: Can be set, 384 bits to 512 bits in 8 bit increments. Default key length: 512 bits.
CALG_SHA SHA hashing algorithm. Must be used for DSS signatures.
CALG_RC2 RC2 block encryption algorithm Key length: 40 to 88 bits.
CALG_RC4 RC4 stream encryption algorithm Key length: 40 to 88 bits.
CALG_CYLINK_ MEK
 DES variant encryption algorithm Key length: 40 bits.