What I Have Learn Today.

Today, Teacher Hani tought us about Clock Speed Measurement. Teacher Hani tought us about the units used in a clock system. There are Megahertz (MHz) and Gigahertz (GHz) and so on.
It was hard to understand for a while, but Teacher Hani divided us into two groups, A and B. My groups win and the end of lesson. Haha..

Explain what is cryptography and firewall.

Firewall is a piece of hardware or software which functions in a networked environment to prevent some communications forbidden by security policy.

We use firewall to prevent hacking (unauthorized access is the use of a computer or network without permission).

Cryptography is a process of transforming plaintext into ciphertext then back again.

Encryption is a process of converting plaintext into ciphertext. Decryption is the process of converting ciphertext into plaintext.

An encryption key is a formula that the sender of that data uses to encrypt plaintext. A decryption key is a formula that the recipient of that data uses to decrypt ciphertext.

Until recently, encryption was used only by intelligence service, militaries, and banks. We use cryptography to secure the information and prevent hacking or unauthorized access.

There are six types of security measures that can be used to protect our computer.

Computer security is a branch of computer technology known as information security as applied to computers and networks. The objective of computer security includes protection of information and property from theft, corruption, or natural disaster, while allowing the information and property to remain accessible and productive to its intended users.

• Antivirus software is used to prevent, detect, and remove malware, including computer viruses, worms, and trojan horses. Such programs may also prevent and remove adware, spyware, and other forms of malware.
• Anti-spyware software is a type of program designed to prevent and detect unwanted spyware program installations and to remove those programs if installed. Detection may be either rules-based or based on downloaded definition files that identify currently active spyware programs. Anti-spyware products are available from a number of vendors, including Sunbelt Software, TrendMicro and Webroot.
• A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications. It is a device or set of devices which is configured to permit or deny computer based application upon a set of rules and other criteria.
• A backup or the process of backing up refers to making copies of data so that these additional copies may be used to restore the original after a data loss event. These additional copies are typically called "backups." The verb is back up in two words, whereas the noun is backup.
• Cryptography is the practice and study of hiding information. Modern cryptography intersects the disciplines of mathematics, computer science, and engineering. Applications of cryptography include ATM cards, computer passwords, and electronic commerce.
• Human security is an emerging paradigm for understanding global vulnerabilities whose proponents challenge the traditional notion of national security by arguing that the proper referent for security should be the individual rather than the state. Human security holds that a people-centered view of security is necessary for national, regional and global stability.

State two differences between worm and viruses.

Virus:

A program that can pass on the malicious code to other program by modifying them.

It attaches itself to the program usually files with .doc, .xls, and .exe.

Worm:

A program that copies itself and spread through the network.

The differences between worm and virus:

• Worm operates through the network while viruses spreads through any medium.

• Worm spread copies of itself as a stand alone program while viruses spread copies of itself as a program that attaches to other program.

Name 4 main sectors that use ICT in their management.

Education:

Teacher and students use computers to research for teaching materials, participate in online forum and online conferences.

Banking:

Businessman can save their time by using online services offered by banks. Customers can make any transaction at 24 hours service centers.

Industry:

Workers can gain help to operate machine by using computers. Researchers can analyze and collect research data for future references.

E-Commerce:

Customers can make buying and selling activities faster and more efficient through internet. Suppliers can also keep track of their transactions.