MIS 3200
Networking Fundamentals

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Sample of Questions asked by students

 

Week 1-Week 4
Question:
What is Circuit switching?
Answer:
Traditionally used in voice networks, circuit switching is a communications method that establishes a dedicated channel (or circuit) between parties involved in a communication. A dedicated circuit means that the circuit is reserved for the duration of the transmission, allowing data (usually voice) to be transmitted in real time. The capacity of the circuit is reserved at each telephone switch and on each transmission line so that the transmission is done without interference or congestion. The Plain Old Telephone Service is a circuit-switched network.
   
Question:
What is Packet switching?
Answer:
A communications method used in data networks for sending packets of information over a network. In packet switching, message are broken up into units called packets (or frames) for transmission. Each packet contains, among other information, the sender's address, the receiver's address, a sequence reference number, a block of data content, and an error-checking code. All the data packets related to a message may not take the same route to get to their destination; they are reassembled once they get to the receiving end
   
Question:
What does Client/Server processing mean?
Answer:
A way of organizing data processing in a network so that the workload is shared between clients computers and server computer(s).The Client is the computer that requests services (e.g. getting a file, print service, etc).The Server, which can be anything from a personal computer to a mainframe, supplies the requested data or services to the Client. In Client/Server processing, the Client executes Client programs (e.g. a Web browser for creating HTTP requests), and the Server executes Server programs (e.g. database management programs for retrieving a required record, server operating system, webservice management program, etc.).
   
Question:
How many Network Interface Cards (NICs) are needed to implement a LAN with 3 servers, 50 workstations and 4 hubs?
Answer:

53 NICs are needed; one NIC for each workstation and server because each computer requires a NIC to get a dedicated connection to the network. NICs have MAC addresses that are included in all messages to be sent. MAC addresses are reference numbers that uniquely identify each computer on the network. Hubs and swithes don't need NICs. That's why we don't need NIC for the 4 hubs.
 
Question:
Why do we say that Hub operation is less secure than Switch operation?
Answer:
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 boadcasts the message out all ports (except for the port the sending device is attached to). So, since all stations receive the message, it is possible to read other people's messages using software called "packet sniffers".
   
Question:
What is the mnemonic usually used to help memorize the 7 layers of the OSI model?
Answer: All
People
Seem
To
Need
Data
Processing
   
Question:
What are the two main components found in any network architecture model?
Answer:
Layers (representing the groups of tasks to be performed), and protocols (or set of rules of communications) are the two main components found in network architecture models.
   
Question:
What is CSMA/CD?
Answer:
CSMA/CD stands for Carrier Sense Multiple Access with Collision Detection. It's the Media Access Control method used in wired Ethernet LANs. When CSMA/CD is implemented in a LAN (through using Ethernet NIC, Ethernet hubs/switches, appropriate type of cable, etc.), networked computers will get access to the network according to the following rule:
1) All computers (“carriers”) listen (“sense”) for traffic on the LAN
2) If there is no traffic, a computer that wishes to transmit may transmit
3) If collision occurs, computers must wait a random amount of time
4) The computer with smallest random number send again first.
   
Question:
What are the primary reasons for internetworking two or more networks?

Answer:

Usually it's one of the following reasons that leads to interconnecting different networks:
(1) Performance decrease: Due to its growth, a LAN can experience a performance decrease (slower transmission speed, more collisions, etc.). In order to fix the problem, the LAN could be broken into segments, and Internetworking devices (like bridges and repeaters) could be used to interconnect the segments.
(2) Need to access resources available on another network: For example, accessing resources on the Internet using routers to connect a LAN to the Internet.
(3) Need to share software & hardware between networks.