Networks quiz#1 solution

1. Cairo University Systems & Biomedical Dept. Fourth Year
Faculty of Engineering Oct 2018 Quiz 1
Networks 15 min
Name: I.D.: ___________________________
Choose the correct answer: [3 pt]
1. Standard protocols are needed to:
a. Choose operating system
b. Specify the media bandwidth
c. allow hardware and software from different vendors to communicate
d. non of the above
2. The advantages of the fiber optic cables are
a. Low error rate and high speed operation
b. Low error rate, high speed operation and ease of handling
c. High error rate and high speed operation
d. Non of the above
3. Average throughput:
a. rate at which bits transferred between sender/receiver at given point in time
b. rate at which bits transferred between sender/receiver during a session
c. rate at which bits transferred between sender/receiver for a period of time
Answer the following questions: Use illustrative GRAPHS
1. [1 pts]What is the difference between a core device and an end system? List different
types of end systems. Is a Web server an end system?
Web server isn’t an end system
2. Suppose Host A sends a large file to Host B. The path from A to B has three links, of
bandwidths R1 = 500 kbps, R2 = 2 Mbps, and R3 = 1 Mbps.
a. [1pt] Assuming no other traffic in the network, what is the expected throughput for the
circuit?
R1
b. [1 pt] Suppose the required data to be transmitted is 4 MB, how long will it take to
reach Host B?
d end-end = L/R1 + L/R2 + L/R3

2. 3. State if the following statements are True or false?[1 pts]
a. A user requests a Web page that consists of some text and four images. For this page, the
client will send one request message and receive five response messages. False
b. Two distinct Web pages (for example, www.mit.edu/research.html and
www.harvard.edu/students.html) can be sent over the same non-persistent connection. False
4. [4 pts] Show graphically the steps needed to download a web page that comprises 3
objects if we utilize
Persistent HTTP Non-Persistent HTTP