IST 220 Networking and Telecommunications, Section 03, Midterm 1 Review

Exam Rules

1. The exam will be held at 1:25-2:15pm (class time), on Wednesday 9/25, in E203 Westgate. Try to come to class a few minutes early. Exam starts right at 1:25pm.

2. The exam is close book and close notes. You can bring one double-sided letter-size cheat sheet. Letter size (8.5" x 11") is the most common printing paper size.

3. You should bring your own calculator to the exam. No computer or other digital device is allowed.

4. You should sit at your assigned seat during the exam. The seat assignment will be displayed on the screen before the exam.

5. Turn in your midterm exam paper AND the cheat sheet.

6. There will be NO make-up examinations unless an official excuse (document) is submitted and pre-approved by the instructor.

Exam Format


Part 1. True or False. (20 points)


Part 2. Choose ONE from the multiple choices. (30 points)


Part 3. Short answer questions. (50 points)

Key Points in Each Chapter


o         This exam covers Chapters 1, 3, 4, 6, 7, and 8.

o         Unless indicated below, the exam will cover all sections in each chapter. It is therefore extremely important for you to thoroughly understand the materials in every section of the textbook. Pay special attention to the key points listed below.

o         All slides can be downloaded from the course website. To prepare for the exam, you should also carefully go through all the slides. Re-do the exercises in the slides.

o         Pay special attention to the homework assignment questions (all questions). The solution will be posted on Canvas after the submission deadline. Carefully compare your answers with the solution, and learn from the mistakes.

Chapter 1. Introduction and Overview

          Packet switching

o         Concepts of packet;

o         The benefits of using packet

          5-layer TCP/IP Internet model

o         Advantage of using a layered model

o         How does it work

          Encapsulation: header, content

          Role of each layer; examples of service provided by each layer


o         How does it work: hosts, hops, number of packets sent

o         How to interpret the result: average delay to remote host, number of networks on the path

Chapter 3. Internet Applications and Network Programming

          Section 3.1 – 3.3 only

          Two communication paradigms (stream vs. message):

o         Concept and characteristics;

o         Pros and cons

Chapter 4. Traditional Internet Applications

          Section 4.1 – 4.23 only

          HTTP: web document transfer protocol

o         Four request types and when they are used

o         Status codes used in HTTP

          DNS service

o         How does it work?

o         DNS hierarchy and server model

o         nslookup

          How does it work?

          Caching and non-authoritative answers

          Types of DNS entries

          Aliases and CNAME type

          Other application-layer protocols: URL, HTML, SMTP, FTP, POP, IMAP

o         What are they & what they are used for?

Chapter 6. Information Sources and Signals

          Section 6.1 – 6.13, 6.17 – 6.19 only


o         Analog vs. digital signals

o         Sine waves and signal characteristics

o         Simple and composite signals

o         Time domain and frequency domain representations

o         Bandwidth (analog & digital signal), bandwidth-limited signals

o         Digital signal levels

o         Baud and bit rate

o         Approximating a digital signal using a bandwidth-limited analog signal

          Converting analog signals to digital

o         Three steps used in pulse code modulation (PCM)

o         The Nyquist theorem and sampling rate

Chapter 7. Transmission Media

          Section 7.1 – 7.10, 7.20 – 7.22 only

          Guided vs. unguided transmission

          Three energy types used in transmission media

          Guided transmission

o         What three types of wiring are used to reduce interference from noise? How do they work?

o         The physics behind each type of wire

o         Pros and cons of coaxial cable, twisted pair, and optical fiber

          Nyquist theorem and Shannon’s theorem:

o         Calculate channel capacity based on the two theorems

o         Significance of these two theorems to telecommunication systems

Chapter 8. Reliability and Channel Coding

          Section 8.1 – 8.11 only

          Concepts: what is the purpose of channel coding

          Single parity checking code: How does it work? How well does it work?

          Row and column (RAC) parity checking code: How does it work? How well does it work?

          Hanming distance: How to compute the distance for a codeword pair?