Answers to Exam 1 Questions

Q.1  Hardware devices like workstations, NIC, media, servers, hubs, nodes and switches
        are used to implement a network. Fill in the blanks in each of the following definitions.

a) A __server________ is a computer that stores the network programs and shared data files that users can get access to.

b) ____switches________ are collection points for wires that interconnect workstations and transmit messages out the single port to which the destination station is connected.

c) ____workstations____ are computers used by users to get services form the network.

d) ____hubs or switches__ are collection points for wires that interconnect workstations.

e) ____nodes or routers__ are computing devices that make decisions as to which route a piece of data will follow next.

f) A __medium_(media)___ is a component used to transfer data in terms of signals in the network.

g) A ___NIC____________ is a device that provide a computer a dedicated connection to the network

Q.2  How many Network Interface Cards (NICs) are needed to implement a LAN with 3 servers, 30 workstations and 4 hubs? Explain why.

Number of NICs needed:	__33_______
Explanation:	A NIC is needed for each workstation and for each server computer. It’s the NIC that provides the workstations and the servers a dedicated connection to the network.

Q.3  Voice communications traditionally use

a.  channel switching

b.  packet switching

c.  both a and b

d.  neither a nor b

Q.4  Data communications normally use

a.  channel switching

b.  packet switching

c.  both a and b

d.  neither a nor b

Q.5  A __Bridge_____ is a connecting device between separate Local Area Networks.

Q.6 A __Router______ is a connecting device between Local Area Networks and

        Wide Area Networks.

Q.7  In Data communications, digital data can be transferred using

        digital signals.                                                                                            T          F

Q.8  In Data communications, digital data can be transferred using

        analog signals.                                                                                           T          F

Q.9  In Data communications, analog data can be transferred using

        analog signals.                                                                                           T          F

Q.10  Usually, when a switch receives a message, it broadcasts the

           received message to all the stations that are connected to it.                    T          F

Q.11  Security is a problem related to Hub operation. Explain.

When a station sends a message, a switch only transmits the message out the port to which the destination station is attached. But in Hub operation, the hub broadcasts the message out all ports to all attached devices. So, since all stations receive the message, it is possible to read other people's messages using software called "packet sniffers"

Q.12    Exhibit

What category of network is illustrated in the exhibit?

a.  Local area network

b.  Metropolitan area network

c.  Broad area network

d.  Campus area network

Q.13  Examples of software programs used at the Application layer of the OSI Reference

          model for creating and transmitting messages include.

a. Electronic Spreadsheets

b. Word processing

c. Web browsers

d. None of the above

Q.14  Examples of Network Architecture Models seen in class include:

        (Circle all correct answers)

a.  OSE Reference Model

b.  Internet Model

c.  Hybrid TCP/IP-OSI Model

d.  All of the above

Q.15  Data Link layer deals with data transport issues.                                      T          F

Q.16  Upper layers of the OSI Reference model are implemented

          in software and hardware.                                                                       T          F

Q.17  Session layer deals with data transport issues.                                          T          F

Q.18  One difference between the Internet Model and the OSI Reference

          Model is that the Internet model has 5 layers instead of 7.                        T          F

Q.19  The second lower-layer (layer 2)of the OSI Reference model is the _Data Link__.

Q.20  The third upper-layer (layer 5) of the OSI Reference model is the __Session____.

Q.21.  Name the two main components of a Network Architecture model.

Answer:	Layers
	Protocols

In Data networks, an application on the sending computer cannot communicate directly with an application on the receiving computer. The communication takes place through Encapsulation/Deencapsulation. Answer the following questions based on your knowledge of the Encapsulation/Deencapsulation processes when the hybrid TCP/IP-OSI model is used.

Q.22  During Encapsulation/Deencapsulation, at which layer of the hybrid TCP/IP-OSI model a trailer is usually added to the message?

a.  Physical

b.  Transport

c.  Data Link

d.  Application

e.  Internet

Q.23  What is called the message created at the Internet layer?

a.  frame

b.  IP packet

c.  TCP segment

d.  datagram

Q.24  What is called the message created at the Data-Link layer?

a.  a frame

b.  an IP packet

c.  a TCP segment

d.  a datagram

Q.25  Which of the following statement(s) is/are true regarding Encapsulation/Deencapsulation?

a. No message is created at the Physical layer

b.  As soon as a message is created at a layer, it is passed down
     to the next lower-layer.

c.  During Deencapsulation process, protocol-related information are removed
     from the received message and passed down to the next lower-layer.

d. None of the above.

Q.26  In which of these Network configurations the File Server system can be implemented:

          (Circle all correct answers)

a. Microcomputer-to-Mainframe

b. Terminal-to-Mainframe

c. Microcomputer-to-LAN

d. All of the above

Q.27  Client/Server systems are found in: (Circle all correct answers)

a. Microcomputer-to-LAN configurations

b. Microcomputer-to-Mainframe configurations

c. Terminal-to-Mainframe configurations

d. Terminal-to-Microcomputer configurations

Q.28. In Client/Server system, the Client could be a terminal and the

          server could be a Mainframe.                                                                      T           F

Q.29. Inquiry/Response applications are typical applications used with

          Terminal-to-Mainframe configuration                                                           T           F

Q.30.  Which of the following are true regarding Client/Server system

a) It is platform independent

b) Heavier processing is done by the client computer

c) The client and the server should have some processing capabilities

d) No processing done by the server

e) All the processing is done by user PC

Q.31.  Which of the following are true regarding File Server System

a) It is platform independent

b) The client and the server should have some processing capabilities

c) No processing done by the server

d) All the processing is done by user PC

Q.32.  Which of the following configuration is used for the Internet
            web service, i.e. for access websites.

a) File Server System access

b) Client/server system

c) Internet access system

d) All of the above