Final answer:
ESP encapsulates the entire IP packet in tunnel mode, providing confidentiality, integrity, and authentication for data communication.
Step-by-step explanation:
In computer networking, ESP (Encapsulating Security Payload) encapsulates the payload of IP packets to provide confidentiality, integrity, and authentication for data communication. In tunnel mode, ESP encapsulates the entire IP packet, including the original IP header, payload, and ESP header, with an additional new IP header. This allows for secure communication between two networks by encrypting and authenticating the data packets.