EC-603-A Data Communication - May 2023 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aList the three techniques in serial transmission and explain the transmission in detail.
   How to answer

   • Define serial transmission and list three techniques: asynchronous, synchronous, isochronous
   • Explain start/stop bits, gaps and timing in asynchronous
   • Explain framing, synchronization and clocking in synchronous/isochronous
   • Compare efficiency, cost and applications with examples
2. 7 Marks
   bWhat is Data Communications? What are its characteristics? Explain.
   How to answer

   • Define data communications as exchange of data between devices
   • List five characteristics: delivery, accuracy, timeliness, jitter
   • Explain each characteristic briefly
   • Give example of data communication system components
3. 7 Marks
   aExplain OSI Reference model with neat figure.
   How to answer

   • List seven layers of OSI model in order
   • Draw neat labelled diagram of layers with peer-to-peer communication
   • Explain function of each layer in brief
   • Mention encapsulation and data flow through layers
4. 7 Marks
   bWhat is Switching? Write the different types of Switching Techniques.
   How to answer

   • Define switching in communication networks
   • List three types: circuit switching, message switching, packet switching
   • Explain principle, phases and resource allocation of each
   • Compare delay, efficiency and applications
5. 7 Marks
   aExplain CRC with an example. How does single bit error differ from a burst error?
   How to answer

   • Define CRC and generator polynomial with modulo-2 division steps
   • Work out example codeword generation and checking at receiver
   • Define single-bit error vs burst error with length concept
   • Explain CRC detection capability for both error types
6. 7 Marks
   bWrite about:

   1. i)Stop and wait protocol
   2. ii)Framing
   3. iii)HDLC
   4. iv)ARQ
   How to answer

   • Explain stop-and-wait protocol operation with ACK and timeout
   • Explain framing need and methods
   • Explain HDLC frame structure, modes and operation
   • Explain ARQ types: Stop-and-Wait, Go-Back-N, Selective Repeat
7. 7 Marks
   aExplain the concept of Token ring (IEEE 802.5).
   How to answer

   • Define token ring and IEEE 802.5 standard scope
   • Explain token passing, frame format and access control
   • Explain ring operation: token capture, data transmission, release
   • Mention monitoring, priority and fault handling
8. 7 Marks
   bExplain LAN with its architecture.
   How to answer

   • Define LAN and its scope/characteristics
   • Describe LAN architecture: topologies, access methods, layers
   • Draw schematic of LAN architecture
   • Give examples and advantages of LAN
9. 7 Marks
   aExplain the structure of TCP/IP protocol.
   How to answer

   • List TCP/IP layers: Network Access, Internet, Transport, Application
   • Draw structure showing protocols at each layer
   • Explain function of each layer briefly
   • Compare with OSI model
10. 7 Marks
    bWrite about Repeaters, Gateway, Bridges.
    How to answer

    • Define repeater function at physical layer
    • Define bridge function and filtering/forwarding
    • Define gateway function for protocol conversion
    • Compare OSI layer of operation and uses
11. 7 Marks
    aExplain different types of Networks.
    How to answer

    • Define network classification criteria
    • Explain LAN, MAN, WAN with range and ownership
    • Give examples and characteristics of each
    • Compare speed, cost and topology
12. 7 Marks
    bWrite about Guided media and Unguided media.
    How to answer

    • Define transmission media and guided vs unguided
    • Explain twisted pair, coaxial, fiber optic with pros/cons
    • Explain radio, microwave, infrared and satellite
    • Compare guided and unguided on key parameters
13. 7 Marks
    aWhat is an Error? Explain the types of errors.
    How to answer

    • Define error in data communication
    • Explain single-bit, multiple-bit and burst errors
    • Give causes: noise, attenuation, interference
    • Mention error detection relevance
14. 7 Marks
    bWrite a short note on X.25 and Frame relay.
    How to answer

    • Define X.25 standard, layers and virtual circuits
    • Explain frame relay principle and frame format
    • Compare speed, error control and overhead
    • Mention applications of both
15. 14 Marks
    Write short notes on:

    1. i)Link state routing
    2. ii)Sliding window
    3. iii)Ethernet
    4. iv)Line encoding
    How to answer

    • Explain link state routing with Dijkstra steps
    • Explain sliding window with sender/receiver windows
    • Explain Ethernet standard, frame and CSMA/CD
    • Explain line encoding need and schemes