Download NUI Galway 2007/2008 Networks & Communications I Exam for Business Info Systems 2nd Year and more Exams Data Communication Systems and Computer Networks in PDF only on Docsity!
Ollscoil na hÉireann, Gaillimh GX_____
National University of Ireland, Galway
Autumn Examinations, 2007/
Exam Code(s) 2BF
Exam(s) 2 nd^ Business Information Systems
Module Code(s) MS
Module(s) Networks & Communications I
Paper No. 1 Repeat Paper Special Paper
External Examiner(s) Professor Hans van der Heijden Internal Examiner(s) Professor J. F. Collins Dr. A. Nachev
Instructions: Answer three questions. All questions carry equal marks.
Duration 2 hrs No. of Answer books
Requirements : Handout MCQ Statistical Tables Graph Paper Log Graph Paper Other Material
No. of Pages Department(s)
SECOND YEAR BUSINESS INFORMATION SYSTEMS
(MS211) NETWORKS AND COMMUNICATIONS I
Time Allowed: TWO hours
Answer THREE questions. All questions carry equal marks.
Q1.
(a) With respect to computer networks, briefly distinguish between each of the following pairs of terms:
i) Network standard vs. network protocol ii) Amplitude modulation (AM) vs. frequency modulation (FM) iii) Unshielded twisted pair (UTP) vs. shielded twisted pair (STP) cables iv) Multimode step-index vs. multimode graded-index optical fibers v) Error-correcting vs. error-detecting codes. (15 Marks)
(b) A data unit is encoded by a sender using Hamming error correcting code. The receiver receives the following bit sequence:
10010100101
that contains the original data unit and redundancy.
Is this data transmission error-free? If not, fix the error. What is the original data unit?
Briefly describe your solution. Presume that only a single-bit error is possible.
Q4.
(a) With respect to Wide Area Networks (WANs), answer the following questions:
i) What is the fundamental difference between circuit switching and packet switching? Why circuit switching is inefficient for the transmission of non-voice data. ii) What are the two routing methods for packet switched networks? iii) Name some advantages of Frame Relay over X.25. iv) Why is Asynchronous Transfer Mode (ATM) technology efficient for data transmission? (15 Marks)
(b) With respect to long-distance wireless communications describe the structure and functioning of each of the following:
i) Satellite navigation systems. ii) Satellite phones. (10 Marks)
(c) Bluetooth technology defines a wireless personal area network (wireless PAN). Briefly discuss the Bluetooth technology. (8 Marks)
Q5. (a) With respect to client/server paradigm answer the following questions:
i) What are the three network application architectures? ii) Distinguish between two-tier architecture, three-tier architecture, and N-tier architecture? iii) What is the fundamental difference between a client and a server? iv) What is middleware? (17 Marks)
(b) With respect to networking and internetworking connecting devices, answer the following questions:
i) What do we mean when we say that a bridge can filter traffic? Why is filtering important? ii) What is the function of a router? How does a router differ from a bridge? How does a multi-protocol router differ from a traditional single-protocol router? iii) How does a brouter decide where an incoming packet should go?
