Communication Network

Communication Network (BA 3rd-4th grade)
“Information Security” in K.G.

Current e-commerce system is implemented on the Internet, and it is accessible from end user’s personal computer and smartphone. Data communication at e-commerce is proceeded according to the Internet protocol. It should be safe and robust, and it is also required to have high efficiency (sending a lot of information with a small communication traffic). In this class, we will learn about the Internet protocol, Web communication, Internet security, information theory and data encoding.


  • You can explain the mechanism of the Internet and the Web.
  • You can explain hierarchical model of information communication.
  • You can explain major protocols of the Internet protocol set.
  • You can explain the procedure of the communication between the Web server and the Web client.
  • You can explain the major types of the unauthorized access and the attacs on servers.
  • You can explain the major types of the security measures on the Internet.
  • You can explain the major types of the security measures on the e-commerce.
  • You can calculate the data quantity in the unit of ‘bit’.
  • You can calculate the information quantity according to the notion of information content.
  • You can calculate the unpredictability of the state according to the notion of entropy.
  • You can evaluate the quality of the encoding.
  • You can encode the messages in a efficient manner.


Day 1: Basics of Web and computer network: How does the Web provide information? What is a computer network (LAN)?
Day 2: Basics of the Internet: What is the structure of the Internet? Is there an address on the Internet?
Day 3: Routing and packet communication: How do you decide the communication route on the Internet? What is a packet?
Day 4: Internet Protocol Part 1: Why do we introduce hierarchy on the communication protocols?
Day 5: Internet Protocol Part 2: How do you translate data on the Internet?
Day 6: Client side Web technology (HTML and DHTML): How is the Web page described? Why products are recommended without any user registration?
Day 7: Internet security: Why computers are hacked? What are security measures on the Internet?

Day 8: Entropy Part 1: What is the unit of data quantity? What is the unit of information quantity?
Day 9: Entropy Part 2: How much value (uncertainty) is there to predict the weather for tomorrow? When does the value (uncertainty) become highest?
Day 10: Entropy Part 3: Do you know the success or failure of an examination in mathematics to know the success or failure of an English test?
Day 11: Data encoding Part 1: How is data encoded during communication? How do you measure the quality of coding?
Day 12: Data encoding Part 2: What are the mechanisms of the basic encoding methods?
Day 13: Data encoding Part 3: How do you encode for detecting errors and for automatically correcting errors?
Day 14: Summary: How do you balance the security measures and the cost?