Match each IPsec component or concept with its function. Internet Protocol Security (IPsec) protects Internet Protocol traffic.

### The pairs\n| Item | Matches | Why |\n|---|---|---|\n| Encapsulating Security Payload (ESP) | Can provide encryption and integrity protection | ESP protects IPsec data and is used by the course VPN with encryption and integrity. |\n| Authentication Header (AH) | Provides integrity and origin authentication without encryption | AH can detect tampering but leaves packet contents readable. |\n| Tunnel mode | Places the original IP packet inside a protected packet with an outer header | Transit routers use the outer addresses to forward the packet. |\n| NAT traversal (NAT-T) | Carries ESP through a Network Address Translation device using User Datagram Protocol (UDP) encapsulation | NAT-T encapsulates ESP in UDP to support passage through NAT. |\n\n### Terms\n- **IPsec**: Internet Protocol Security, a set of protections for IP traffic.\n- **UDP**: User Datagram Protocol, a transport protocol used here to encapsulate ESP.\n\n### Remember\nESP can encrypt; AH does not, and tunnel mode adds an outer packet.