Impedance - Computer Networks - Old Exam Paper, Exams of Computer Networks

Download Impedance - Computer Networks - Old Exam Paper and more Exams Computer Networks in PDF only on Docsity! Cork Institute of Technology Higher Certificate in Science in Computing (ACCS) – Stage 1 (NFQ Level 6) January 2007 Computer Networks 1 (Time 3 Hours) Answer five questions. Examiners: Ms. T. Murphy All questions carry equal marks. Ms. M. Meagher Ms. A. Brown Q1. (a) Explain the term local area network. (4 marks) (b) Define the term protocol. What are the principal functions of protocols? (4 marks) (c) Explain, with the aid of a diagram, a star topology. What are the advantages and disadvantages of this topology? (5 marks) (d) Explain in detail each layer of the OSI model. (7 marks) Q2. (a) Explain the following terms. (i) Impedance (ii) Attenuation (iii) Latency (iv) Propagation (4 marks) (b) In the context of cabling, explain noise and the different types of noise. List some techniques that are used to minimize noise. (6 marks) (c) List some of the characteristics of twisted wire and fibre optic cabling. What are the advantages and disadvantages of each? (6 marks) (d) Give a brief explanation of the following devices: (i) Repeater (ii) Router (4 marks) 2 Q3. (a) Explain the differences between the classes of IP addresses. (3 marks) (b) Explain whether each of the following addresses are host, network or broadcast addresses: 142.20.60.63 /19 199.100.250.32 /29 220.21.7.130 /27 182.0.36.119 /22 (4 marks) (c) Given the IP Address 166.78.192.74/21. Can you answer the following? a) The Default and new Subnet Mask? b) The Network Address for that subnet? c) The Range of Usable IP Addresses within that subnet? d) The Broadcast Address for that subnet? e) Can this address be used on the internet? Why or why not? (5 marks) (d) Given a network address of 193.43.211.0. Devise an IP Addressing scheme that will allow 28 hosts per network. (a) What will the new subnet mask be? (b) List the network addresses of the new subnets created? (c) What is the Network Address of the 3rd Usable Subnet? (d) What is the Broadcast Address of the 3rd Usable Subnet? (e) What is the Range of Hosts on the 3rd Usable Subnet? (8 marks) Q4. (a) Show the Ethernet 802.3 frame structure. Describe the function of each of the parts. (6 marks) (b) List 3 types of collisions and explain each one. (4 marks) (c) Explain the term CSMA/CD. (6 marks) (d) Give a brief explanation of each of the following, include what devices and cabling types can be used for each: 10Base-2 100Base-TX 1000Base-LX (4 marks)