IPSEC (Internet Protocol Security): Set of protocols that provide a cryptographic layer to IP
traffic (IPv4 and IPv6). It can use AH (Authentication Header) to provide Authentication and
Integrity for each packet, ESP (Encapsulation Security Payload): Provides confidentiality, and it
can provide Authentication and Integrity. SA (Security Association):Simplex one-way communication
(Like a walkie talkie).IKE (Internet Key Exchange): IPSEC can use different types of encryption and
hashes. For example, it can use MD5 or SHA-1/2 for integrity, and 3DES or AES for confidentiality.
IKE negotiates the algorithm selection process. The 2 sides of an IPSEC tunnel will normally use IKE
to negotiate to the highest and fastest level of security, selecting AES over single DES for
confidentiality if both sides support AES, for example.