IP Security components

IP Security (IPSec) is a protocol suite that provides security to IP communication by encrypting the traffic and authenticating the sender. The components of IPSec are:

1. Authentication Header (AH)

Authentication Header (AH) provides authentication and integrity to the IP packets. It adds a header to the IP packet that contains a cryptographic hash of the packet contents. The hash is generated using a shared secret key between the sender and receiver. AH does not provide confidentiality, meaning that the packet contents are not encrypted.

2. Encapsulating Security Payload (ESP)

Encapsulating Security Payload (ESP) provides confidentiality, authentication, and integrity to the IP packets. It encrypts the packet contents using a shared secret key between the sender and receiver. ESP also adds a header to the IP packet that contains the authentication and integrity information.

3. Internet Key Exchange (IKE)

Internet Key Exchange (IKE) is a protocol used to establish a secure communication channel between the sender and receiver. IKE uses a combination of public-key and symmetric-key cryptography to exchange the secret keys used by AH and ESP. IKE also negotiates the security policies used by AH and ESP.

4. All of the mentioned

All of the mentioned components are included in IPSec. AH provides authentication and integrity, ESP provides confidentiality, authentication, and integrity, and IKE establishes the secure communication channel and negotiates the security policies. Together, these components provide a comprehensive security solution to IP communication.

AH ensures that there is no retransmission of data from an unauthorized source, and protects against data tampering. ESP provides with content protection and ensures that there is integrity and confidentiality for the message.