What is the role of IKE in IPsec?

• A. It negotiates cryptographic keys and SA parameters
• B. It handles user authentication
• C. It routes packets
• D. It provides certificate revocation

Answer: (A)

IKE is the mechanism that sets up IPsec by establishing trust and the cryptographic foundation for protected traffic. It negotiates the cryptographic algorithms to use, the lifetimes and parameters of the security associations, and it derives the keying material that will actually encrypt and authenticate IPsec packets. It also handles mutual authentication between the peers as part of establishing these associations. Once the IKE negotiations complete, IPsec can use the agreed IPsec SAs to protect data traffic. Routing and certificate revocation are separate functions, and end-user authentication isn’t the primary role of IKE.