Office Use Only Monash University Faculty of Information Technology Sample Exam Paper EXAM CODES: FIT1005 TITLE OF PAPER: Networks and Data Communications EXAM DURATION: 180 minutes writing time READING TIME: 10 minutes THIS PAPER IS FOR STUDENTS STUDYING AT: ( tick where applicable) Berwick Clayton Malaysia South Africa Caulfield Peninsula Candidates must complete this section STUDENT ID ___ ___ ___ ___ ___ ___ ___ ___ DESK NUMBER ___ ___ ___ ___ During an exam, you must not have in your possession, a book, notes, paper, calculator, pencil case, or other material/item which has not been authorised for the exam or specifically permitted as noted below. Any material or item on your desk, chair or person will be deemed to be in your possession. You are reminded that possession of unauthorised materials in an exam is a discipline offence under Monash Statute 4.1. Candidates are reminded that they should have no material on their desks unless its use has been specifically permitted by the following instructions. AUTHORISED MATERIALS CALCULATORS YES NO OPEN BOOK YES NO SPECIFICALLY PERMITTED ITEMS YES NO INSTRUCTIONS TO CANDIDATES 1. This Exam consists of: Part A – 20 Multiple Choice Questions (1 mark per question is 20 marks) Part B – 7 Questions (70 marks) Part C – 2 Scenario Questions (30 marks) Total 120 marks. 2. Write your ID number and Desk number in the section above. 3. Attempt all parts. Multiple choice answers must be circled on the exam paper. 4. This Examination Paper MUST NOT be taken from the Examination Room. It must be placed in the front of your exam script book. Part A – Multiple Choice Questions (20marks) There is only one correct answer for each question; no marks are deducted for incorrect answers. Please circle your answers on this sheet Q1. Which OSI Model layer is the fourth layer above the physical layer? a) Session b) Transport c) Application d) Physical e) None of the above Q2. Rank the following transmission media (optical fibre, coaxial cable and twisted pair) according to their channel capacity from the highest to the lowest. a) Optical Fibre, Coaxial Cable, Twisted Pair. b) Optical Fibre, Twisted Pair, Coaxial cable. c) Twisted Pair, Coaxial Cable, Optical Fibre. d) Coaxial cable, Optic fibre, Twisted Pair. e) None of the above Q3 As a user’s message moves from the lowest layer to the top layer of the OSI Model, protocol headers are: a) Added b) Removed c) Rearranged d) Modified e) None of the above Q4. Which of the following transmission impairments adds unwanted signals to a transmitted signal? a) Attenuation b) Delay Distortion c) Crosstalk d) Attenuation Distortion e) None of the above Q5. What is the bandwidth of a signal that ranges from 35 kHz to 95 kHz? a) 130 kHz b) 60 kHz c) 35 kHz d) 95 kHz e) None of the above Q6. A television (TV) transmission is an example of which type of transmission? a) Simplex b) Half duplex c) Full duplex d) Automatic e) None of the above Part A – Multiple Choice Questions (20marks) There is only one correct answer for each question; no marks are deducted for incorrect answers. Please circle your answers on this sheet Q7. According to Nyquist’s theorem, the maximum transmission rate (in bps) on a noiseless channel for a given bandwidth is: a) Half the bandwidth b) Equal to the highest signal frequency c) Twice highest signal frequency d) Twice the bandwidth e) None of the above Q8. In asynchronous transmission: a) a start bit is needed before the transmission of a byte b) no stop bit is required c) a character consists of 5 bits d) a stop bit returns the line to the non-idle state e) None of the above Q9. In the “Go-Back-N” ARQ mechanism, the maximum window size for a k-bit sequence number field in information frames is: a) k b) k+1 c) 2k d) 2k-1 e) None of the above Q10. What topology is illustrated in the diagram below? a) b) c) d) e) Star Bus Tree Ring None of the above Part A – Multiple Choice Questions (20marks) There is only one correct answer for each question; no marks are deducted for incorrect answers. Please circle your answers on this sheet Q11. Which of the following Ethernet standards does not utilize the CSMA/CD access method? a) 1000 Mbps Ethernet b) 500 Mbps Ethernet c) 100 Mbps Ethernet d) 10 Mbps Ethernet e) None of the above Q12. Which LAN standard has the highest data rate? a) 10Base5 b) 10Base-T c) Twisted Pair Token Ring d) FDDI e) None of the above Q13. Which of the following IP Network addresses is a reserved address? a) 127.0.0.0 b) 130.50.0.0 c) 197.65.10.0 d) 4.0.0.0 e) None of the above Q14. When installing an Ethernet 10BASE-T network, what type of cable is used? a) Fiber Optic b) Coaxial Cable c) Twisted Pair d) Wireless e) None of the above Q15. The key requirement/s for a routing function in packet-switching networks is/are: a) Efficiency b) Correctness, Simplicity and Fairness c) Optimality, Robustness and Stability d) All of the above e) None of the above Q16. In alternate routing scheme (circuit-switched networks), the responsibility to select the appropriate route for each call rests on the: a) End station b) Routing station or switch at mid-point c) Originating switch d) End station and the originating switch e) None of the above Part A – Multiple Choice Questions (20marks) There is only one correct answer for each question; no marks are deducted for incorrect answers. Please circle your answers on this sheet Q17. In packet switched networks that use distributed routing: a) The central node typically makes use of information obtained from all nodes for the purpose of forwarding packets b) Each node has the responsibility of selecting an output link for routing packets as they arrive, based on a routing table c) A routing decision is made by source only d) A routing decision is made by the central node based on best performance criteria e) None of the above Q18. Which of the following sequences best describes the establishment, communication and termination of a communication session using a packet switched network? a) Setup, Data transfer, Disconnect b) Data Transfer, Disconnect c) Dial, Data Transfer, Disconnect d) Dial, Setup, Data Transfer e) None of the above Q19. A typical digital telephone channel in TDM circuits is allocated a speed of a) 4 kbps b) 8 kbps c) 64 kbps d) 1.544 Mbps e) None of the above Q20. Which of the following is not a WAN technology? a) X.25 b) Frame Relay c) ATM d) TCP/IP e) None of the above Part B – Questions (70marks) Q1. Discuss in detail, the reasons why a layered Network Architecture Model is used to construct a communications network. (10 marks) Q2. In relation to modulation and data encoding: a) Define the term modulation. b) Given a bit string, 001110101, show via a diagram how it can be encoded on to a sine wave analog signal using Amplitude Shift Keying (ASK). c) Define and discuss in detail, using an example to illustrate each, the following transmission modes: i) Simplex ii) Half-Duplex ii) Full-Duplex d) Define the following characteristics in relation to the simple sine wave model for an analog signal: i) Amplitude ii) Frequency iii) Phase (2 + 2 + 3 + 3 = 10 marks) Q3. In relation to Local Area Networks: a) What is the main downfall of the Carrier Sense Multiple Access (CSMA) method? How do Collision Detection (CD) methods help alleviate this problem? b) What fields are contained in a Medium Access Control (MAC) frame? Describe three of these. c) What are the differences between half and full duplex Ethernet? What happens to the theoretical transfer rate when a full duplex transmission mode is used? (3 + 4 + 3 = 10 marks) Q4. a) b) c) d) Identify the disadvantages of fragmenting data. Discuss two of these disadvantages. What is the role of sequencing in a connection-oriented data transfer? Why are global and device-level addressing systems necessary? In what scenarios are priority and QoS (Quality of Service) protocol services useful (3 + 2 + 2 + 2 = 10 marks) Q5. In relation to routing in switched networks: a) Explain the routing technique known as “flooding.” b) What are the main advantages of this technique? c) What are the main disadvantages? (4 + 3 + 3 = 10 marks) Q6. Discuss in detail and compare the following modes of data transmission on a communication link. Use diagrams to help illustrate your answers. a) Asynchronous transmission. b) Synchronous transmission. (5 + 5 = 10 marks) Q7. a) b) List three advantages of the packet switching technique compared with that of circuit switching. Define the following terms in the context of message delivery over a network, and link utilization. i. Propagation delay. ii. Transmission time. iii. Node delay. (4 + 2 + 2 + 2 = 10 marks) Part C – Scenario Question (30marks) Q1. You have been asked to configure the hardware for a LAN to provide office automation capabilities for a factory. The Factory Manager has asked you to provide a LAN that will make use of four IBM compatibles with 128 MB of memory, two IBM compatibles with 256 MB of memory, two IBM compatibles with 512 MB of memory, a photocopier, a laser printer and two ink jet printers. In addition, some employees will need to access the LAN from home to transfer files and to do remote printing. There are currently no network facilities installed in the factory. Each of the printers is attached to one particular desktop, and the photocopier is not attached to any computers. Using a physical star topology, draw a network diagram of your proposed LAN. Label all hardware components in your diagram. Support your network diagram, by providing an explanation of the following: i. ii. Q2. equipment, software, and cabling that will be needed to connect each device to the LAN details of configuration of the hardware, software, and communications capabilities required at the LAN and home user ends of the connection. A company has two large computers connected by a synchronous communication line having a speed of 56kbps. These computers are 300 kilometres apart. Each location also has a LAN. The company wants to allow all computer users, those connected to the LANs as well as those connected to the large computers, to be able to communicate. Is the current connection sufficient for the proposed configuration? Why or why not? Explain your answer. (20 + 10 = 30 marks) - END OF EXAM -