Daffodil International University
Department of Computer Science and Engineering Faculty of Science and Information Technology
Midterm Examination, Semester: Spring 2020
Course Code: CSE 313 (Day) Course Title: Computer Network Total Marks: 25 Time: 1.5 Hours Answer all of the following questions. Figures in the right-hand margin indicate full marks.
[1] a) Suppose, you are working in a data center environment and you are assigned the network address 150.60.0.0/16. Prepare an IP addressing plan that allows 16 usable hosts in each subnet and answer the following questions:
I. Find out total number of subnets.
II. Find out the custom subnet mask.
III. What is the network address of 3rd usable subnet?
IV. What is the broadcast address of 4th usable subnet?
V. What are the first and last valid host of 5th usable subnet?
b) Considering the following diagram, show the operation of Link State Routing Technique for computing the least cost path from A to all destinations. Also explicitly list all the shortest path routes from A to all destinations.
c) Find the summarized IP address with subnet mask from the following IP addresses.
10.16.0.0/27, 10.16.0.5/27, 10.16.0.9/27, 10.16.0.10/27, 10.16.0.12/27, 10.16.0.35/27
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5
3
[2] a) How does it takes a packet of length 2 Megabyte to propagate over a link of distance 3000 km? Where propagation speed 2.5 × 108 m/s and transmission rate 1 Mbps.
b) Compare between packet switching and circuit switching.
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2 [3] a) Why centralized DNS is not practically used? Differentiate between Iterated
Query and Recursive Query of DNS Name Resolution with appropriate diagram.
b) Suppose Rahim, with a Web-based e-mail account (such as [email protected]) sends a message to Marium ([email protected]), who accesses her mail from her mail server using POP3. Discuss how the message gets from Rahim’s host to Marium’s host and also list the series of application-layer protocols that are used to move the message between the two hosts.
1+3
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