Which phase of IKE is responsible for establishing a secure channel between peers?

• A. Phase 4
• B. Phase 2
• C. Phase 1
• D. Phase 3

Answer: (C)

Phase one is responsible for establishing a secure channel between peers. In this phase, the two endpoints authenticate each other and negotiate the cryptographic parameters so that an IKE Security Association is created. This secure tunnel serves as the protected channel over which further negotiations occur. Once this channel is in place, the next phase uses it to negotiate the actual IPsec security associations that will protect the data traffic. Phase three isn’t used to establish that initial secure channel in the standard model, so it doesn’t perform that setup.