•What is a replay attack?
This material may consist of step-by-step explanations on how to solve a problem or examples of proper writing, including the use of citations, references, bibliographies, and formatting. This material is made available for the sole purpose of studying and learning - misuse is strictly forbidden.AH (Authentication Header) provides message authentication, but also anti-replay attack protection. Despite the fact of being considered deprecated (in the context of message authentication) for new applications (as it is also stated in the book on page 630), it can be used in conjunction with ESP (Encapsulating Security Payload) for offering increased level of security for the message. The specification of AH header can be found in RFC 4302. ESP performs both authentication and encryption as main services and RFC 4303 mentions this as well. By regarding the services offered from CIA triad angle (confidentiality-integrity-availability) it can be stated that AH provides data integrity (by protecting the datagrams from the IP header to the transport header), while ESP achieves confidentiality (by encrypting the payload of the packet) and integrity (since it is capable of protecting the payload in the same manner like AH and contributes to message authentication)....