Code: cnsElectronics & Comm. Eng.5th Semester2 Examination Papers

COMPUTER NETWORKS & SECURITY

Official Bihar Engineering University examination question papers, marks distribution, and questions transcript. Available exam sessions: 2025, 2020.

Exam Year:

Get Instant AI Answers on this Paper

Open BEU Connect Android app to solve any numerical or derive formulas step by step.

Ask AI in App
Official Exam Paper TranscriptB.Tech 5th Semester Examination, 2025
Bihar Engineering University, Patna
B.Tech 5th Semester Exam., 2025

Computer Networks and Security

Time: 03 HoursCode: 104501Semester: VFull Marks: 70

Instructions:

  1. The marks are indicated in the right-hand margin.
  2. There are NINE questions in this paper.
  3. Attempt FIVE questions in all.
  4. Question No. 1 is compulsory.
Q.1 Choose the correct option / answer the following (Any seven question only):[2 x 7 = 14]

  1. In computer network which of the following is an example of guided transmission media?

    1. Radio waves
    2. Microwave
    3. Optical fiber
    4. Infrared

  2. Which techniques is used in Cyclic Redundancy Check?

    1. XOR Encryption
    2. AND operation
    3. OR operation
    4. Modulo-2 Division

  3. Multiple access protocol which is used carrier sensing and collision detection?

    1. CSMA/CD
    2. CDMA/CA
    3. Pure ALOHA
    4. Slotted ALOHA

  4. What is the primary function of packet forwarding at the network layer?

    1. Delivering packets to their next hop on the path to the destination
    2. Assigning IP addresses
    3. Encrypting data
    4. Fragmenting packets

  5. One of the features that is provided by TCP but not by UDP?

    1. Error detection
    2. Connection-oriented communication
    3. Broadcasting
    4. Fast delivery

  6. Which protocol is used for monitoring and managing network devices?

    1. DNS
    2. SNMP
    3. SMTP
    4. FTP

  7. A hash function takes an input message and returns ...................

    1. a fixed-size string of characters
    2. a variable-size string of characters
    3. input size string characters
    4. a public-private key pair

  8. What is the main idea behind the RSA public-key encryption algorithm?

    1. Using a single symmetric key
    2. Hiding the IP address of the sender
    3. Using large prime numbers and modular arithmetic
    4. Using XOR operations on data

  9. The primary function of a Virtual Private Network is?

    1. Creates a secure tunnel over a public network for private communication
    2. Acts as a physical router
    3. Assigns MAC addresses dynamically
    4. Encrypts DNS records only

  10. In SSL architecture, which protocol is responsible for managing encryption, compression, and message integrity?

    1. SSL Handshake Protocol
    2. SSL Alert Protocol
    3. SSL Record Protocol
    4. Change Cipher Spec Protocol
Q.2 Solve both questions :[7 x 2 = 14]

  1. Describe various network topologies used in computer networks.

  2. Discuss Frequency Division Multiplexing, Time Division Multiplexing, Wavelength Division Multiplexing.

Q.3 Solve both questions :[7 x 2 = 14]

  1. Explain its features and advantages over TCP and UDP. Discuss the concept of congestion control in SCTP.

  2. Illustrate Logical addressing – IPv4, IPv6.

Q.4 Solve both questions :[7 x 2 = 14]

  1. Differentiate between wired LAN and wireless LAN. Discuss the concept a Virtual LAN.

  2. Explain the OSI reference model in detail. How it is different from TCP/IP model.

Q.5 Solve both questions :[7 x 2 = 14]

  1. Explain the working principles of Pure ALOHA, Slotted ALOHA, CSMA/CD, and CSMA/CA with their applications.

  2. Explain the Sliding Window Protocol and Piggybacking technique. How do these methods improve data transmission efficiency in computer networks?

Q.6 Solve both questions :[7 x 2 = 14]

  1. What is the size of an ARP packet when the protocol is IP and the hardware is Ethernet?

  2. Discuss Three-ways Handshaking in a TCP connection.

Q.7 Solve both questions :[7 x 2 = 14]

  1. Define Internet Protocol. Is the size of the ARP packet fixed? Explain.

  2. An IP datagram must go through router 128.46.10.5. There are no other restrictions on the routers to be visited. Draw the IP options with their values.

Q.8 Solve both questions :[7 x 2 = 14]

  1. Discuss Digital Signatures. Explain Secret-key signature and Public-key signature.

  2. The Diffie-Hellman key exchange is being used to establish a secret key between Alice and Bob. Alice send Bob (719, 3, 191). Bob respond with (543). Alice’s secret key, x, is 16. Explain the secret key with the help of above example.

Q.9 Write short notes on any two of the following:[7 x 2 = 14]

  1. Token Bucket algorithm

  2. File Transfer Protocol

  3. Secure Socket Layer and Transport layer Security

  4. Error control protocols

Related Official Syllabus

Linear Control System

104501

Official BEU curriculum units & topics for this examination subject.

Unit 1.0: Basics of Control Systems (6 hrs.)

Concepts of Control Systems • Open Loop and closed loop control systems and their differences • Different examples of control systems • Effects of feedback

Unit 2.0: Mathematical Modeling & Transfer Function (6 hrs.)

Transfer Function Representation • Block diagram representation of systems considering electrical systems as examples • Block diagram Reduction • Representation of Block diagram by Signal flow graph • Reduction using Mason’s gain formula

Unit 3.0: Time Response Analysis (8 hrs.)

Standard test signals • Time response of first order systems • Characteristic Equation of Feedback control systems • Transient response of second order systems • Time domain specifications • Steady state response • Steady state errors and error constants • Effects of proportional derivative, proportional integral systems

Unit 4.0: Stability Analysis (8 hrs.)

The concept of stability • Routh’s stability criterion • Qualitative stability and conditional stability • Limitations of Routh’s stability • Root Locus Technique: The root locus concept • Construction of root loci • Effects of adding poles and zeros to G(s) H(s) on the root loci

Unit 5.0: Frequency Response Analysis (10 hrs.)

Frequency domain specifications • Bode diagrams • Determination of Frequency domain specifications and Phase margin and Gain margin • Stability Analysis from Bode Plots • Polar Plots, Nyquist Plots Stability Analysis • Compensation techniques — Lag, Lead, and Lead-Lag Compensators • Compensation Using P, PI, PD, PID Controllers

View Complete 5th Semester Syllabus

Prepare Better with BEU Connect

  • Download papers for 100% offline study
  • Ask AI for step-by-step problem breakdown
  • Attempt official GATE CBT mock tests
  • Calculate SGPA and track attendance
Download Android App