Which algorithm does ISAKMP use to securely derive encryption and integrity keys?

RSA is an asymmetric algorithm primarily used for digital signatures and encryption of small amounts of data, such as a symmetric key, but not directly for the secure derivation of session keys in the way Diffie-Hellman does in ISAKMP.

AES (Advanced Encryption Standard) is a symmetric encryption algorithm used for data confidentiality, not for the secure derivation of the keys themselves within ISAKMP.

3DES (Triple Data Encryption Standard) is a symmetric encryption algorithm used for data confidentiality, similar to AES, and is not responsible for the secure derivation of session keys in ISAKMP.

The Diffie-Hellman (DH) key exchange algorithm is fundamental to ISAKMP (Internet Security Association and Key Management Protocol) because it enables two parties to securely establish a shared secret key over an insecure communication channel, which is then used to derive the encryption and integrity keys for IPSec.