and anti-replay services. These protocols can be used alone or in combination. Basic components include: Security protocols for AH and ESP Security association for policy management and traffic processing Manual and automatic key management for the Internet key exchange (IKE) Algorithms for authentication and encryption The algorithm allows these sets to work independently without affecting other parts of the implementation. The IPsec implementation is operated in a host or security gateway environment giving protection to IP traffic. Threat modeling Threat Modeling tools helps you to proactively analyze the cyber security posture of a system or system of systems and in that way prevent security threats. Multi-factor authentication Multi-factor authentication (MFA) is an access control method of in which a user is granted access only after successfully presenting separate pieces of evidence to an authentication mechanism – two or more from the following categories: knowledge (something they know), possession (something they have), and inherence (something they are). Internet resources, such as websites and email, may be secured using this technique. Security token Some online sites offer customers the ability to use a six-digit code which randomly changes every 30–60 seconds on a physical security token. The token has built-in computations and manipulates numbers based on the current time. This means that every thirty seconds only a certain array of numbers validate access. The website is made aware of that device's serial number and knows the computation and correct time to verify the number. After 30–60 seconds the device presents a new random six-digit number to log into the website. Electronic mail security Background Email messages are composed, delivered, and stored in a multiple step process, which starts with the message's composition. When a message is sent, it is transformed into a standard format according to RFC 2822. Using a network connection, the mail client sends the sender's identity, the recipient list and the message content to the server. Once the server receives this information, it forwards the message to the recipients. Pretty Good Privacy (PGP) Pretty Good Privacy provides confidentiality by encrypting messages to be transmitted or data files to be stored using an encryption algorithm such as Triple DES or CAST-128. Email messages can be protected by using cryptography in various ways, such as the following: Digitally signing the message to ensure its integrity and confirm the sender's identity. Encrypting the message body of an email message to ensure its