Q16Information Security Systems
Question
4 marks
Discuss the architecture of IPSec, including its AH and ESP protocols.
Answer
IPSec secures IP communications via Authentication Header (AH) and Encapsulating Security Payload (ESP).
Internet Protocol Security (IPSec) is a suite of protocols for securing network layer communications. The Authentication Header (AH) protocol provides data origin authentication, data integrity, and anti-replay protection, but no confidentiality. The Encapsulating Security Payload (ESP) provides confidentiality (encryption) along with optional authentication and integrity. IPSec operates in two modes: Transport mode (encrypts payload only) and Tunnel mode (encrypts entire IP packet, used in VPNs).