Order the main Internet Key Exchange version 2 (IKEv2) exchanges for initial peer negotiation and protected traffic.

### The order\n1. **The peers use IKE_SA_INIT to agree on initial parameters and exchange key-agreement values.** This creates the basis for protecting later IKE messages.\n2. **The peers use IKE_AUTH to authenticate and establish the first Child Security Association (CHILD SA).** Identity and authentication are checked before the traffic association is set up.\n3. **The peers carry user traffic protected by the negotiated IPsec association.** Protected traffic follows successful negotiation.\n\n### The concept\nThe IKE SA protects control exchanges; the CHILD SA carries the negotiated protection for user data.\n\n### Terms\n- **IKEv2**: Internet Key Exchange version 2, the peer-negotiation protocol.\n- **IPsec**: Internet Protocol Security, protection for IP traffic.\n\n### Remember\nInitial negotiation comes before authentication, and user traffic follows the data association.