Security in Computer Science is the act of protecting a computer system physically and virtually. This means that there will protection on the hardware of a computer system and the software’s or any data inside a computer system. This involves a set of techniques to protect one’s confidentiality, integrity, and availability. Confidentiality is when only certified people have access to specified computer systems and data. Integrity is when only certified people have access to use or change systems and data. Finally, Availability is when certified people have access to their own systems and data.

When planning for security it is important to picture out who you are defending against. This can be referred to as “threat model”. Attackers won’t all be the same, some attackers may use simple moves and some others might use complex moves. This is something that must be heavily considered in detail when planning a security system.

For a computer system to identify whether a user is certified to have access to the data, it uses a method called Authentication. There are three different types of authentication, what you know, what you have, and what you are. “What you know” authentication is the use of usernames and passwords. This is the most known way and the easiest to implement, however it can be broken if the attacker knows the secret to the password or has been given the password. There are easy ways for a computer to track down a password if it’s a short one, for example a four-digit pin. “What you have” authentication is a physical key that the user only has. This can be a key to a lock that only the person has. This is harder to crack because it requires a physical key, although keys can still be stolen or made copies of. “What you are” authentication is when you are present in front of the computer system to present yourself. This can be made in the form of finger print scanner or face recognition. Moreover, this type of authentication is heavily secured its still expensive.

Altogether these three types of authentication have their advantages and disadvantages. This is why security professionals advise people to use more than one type of authentication to reduce the probability of being attacked.

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