# Appendix C: IBMJCE Keysize Restrictions

The IBMJCE provider enforces the following restrictions on the keysize passed to the initialization methods of the following classes:

- KeyGenerator
- Restrictions (by algorithm):
**DES**: keysize must be equal to`56`

**Triple DES**: keysize must be equal to`112`

or`168`

Note: A keysize of`112`

will generate a Triple DES key with 2 intermediate keys, and a keysize of`168`

will generate a Triple DES key with 3 intermediate keys.**Blowfish**: keysize must be a multiple of`8`

, and can only range from`32`

to`448`

, inclusive

- KeyPairGenerator
- Restrictions (by algorithm):
**Diffie-Hellman**: keysize must be a multiple of`64`

, and can only range from`512`

to`2048`

, inclusive

- AlgorithmParameterGenerator
- Restrictions (by algorithm):
**Diffie-Hellman**: keysize must be a multiple of`64`

, and can only range from`512`

to`2048`

, inclusive