Lecture 1 : Introduction to Information Security

We were given an introduction on information security. In this lesson, we have learnt about:

• · What is Security?
• · Security Architecture
• · Security Principles
• · Security Policy
• · Security Attacks/Threats
• · Methods of Defense
• · Security Services
• · Security Mechanisms

Security is clearly defined as the state of being secure that is free from danger and threats, as well as to be protected from adversaries, which are those who would intentionally or unintentionally do harm. Information security is the protection of information and systems and hardware that use, store and transmit information.

The table above shows the security trends of today. We see that normal users are capable of hacking using only little amount of knowledge and hacking tools.

Security involves three areas namely, detection by using scanners, prevention by using tools such as proxy and firewall, and recovery using tools regarding cryptography techniques and proper planning.

The security architecture is defined by ITU-T Recommendation X.800 and was developed as an international standard for computer and communications vendors to develop security features for their products and services related to structured definition of services and mechanisms. This architecture focuses on security attacks, mechanisms and services.

When it comes to information security, three security principles are being addressed namely confidentiality, integrity, and availability.

However, the correct balance must be done among these principles to achieve a secure system, which is normally impossible to achieve.

The security policy is a set of rules that applies on security-relevant activities in a security domain. Some of the key aspects related to security policy are authorization, access control policy and accountability.

According to the security attacks or threats defined in the X.800 and RFC 2828 documents, security attacks are classified into two, which is the passive attack that only involves eavesdropping with motives of obtaining information that is being transmitted, while the other being the active attack that involves modification of the data stream or creation of false stream with motives of obtaining authorization.

Methods of defense can be done against harm that occurs when threats are detected. This is by prevention, deterrence, deflection, detection and recovery.

Methods of defense in terms of control involve encryption, software access controls, hardware controls, policies that are agreed among users and physical controls.

Security services are divided into a few types:

• Authentication, an assurance that the communicating entity is the one claimed to be.
• Access Control, prevention of unauthorized personnel who misuse resources.
• Data Confidentiality, protection of data from unauthorized disclosure.
• Data Integrity, the assurance that received data is as sent by an authorized entity.
• Non-repudiation, protection against denial by one of the parties in a communication.

A security mechanism is any kind of process or a device incorporating the process that is designed to detect, present or recover from a security attack.

Security mechanisms are divided into two namely Specific Security Mechanisms and Pervasive Security Mechanisms.