AL-602 Computer Networks - Jun 2026 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
   aDefine Computer Network. Explain its goals, components, and applications.
   How to answer

   • Definition of computer network as interconnection of autonomous computers for resource sharing
   • Goals: resource sharing, reliability, cost saving, communication, scalability
   • Components: nodes, links, NIC, switches, routers, protocols, transmission media
   • Applications: email, file sharing, WWW, e-commerce, remote access
2. 7 Marks
   bCompare the OSI Reference Model and TCP/IP Model with suitable diagrams.
   How to answer

   • Draw 7-layer OSI and 4-layer TCP/IP models side by side
   • Explain function of each layer in both models
   • Compare on basis of layers, approach, reliability, protocols
   • Merits/demerits and usage conclusion
3. 7 Marks
   aDiscuss design issues in computer networks and explain the concepts of connection-oriented and connectionless services.
   How to answer

   • List design issues: addressing, routing, error control, flow control, multiplexing, scalability
   • Explain reliability, naming, service primitives, connection management
   • Define connection-oriented service with example TCP
   • Define connectionless service with example UDP and comparison
4. 7 Marks
   bExplain the principles of Physical media, bandwidth, data rate, and data modulation.
   How to answer

   • Define guided/unguided physical media with examples
   • Define bandwidth vs data rate and Nyquist/Shannon relation
   • Explain data modulation need and AM, FM, PM/digital techniques
   • Relation of bandwidth, data rate and channel capacity
5. 7 Marks
   aExplain the functions of the Data Link Layer. Discuss framing techniques in detail.
   How to answer

   • Functions: framing, error control, flow control, access control, addressing
   • Character count, byte stuffing/flag bytes
   • Bit stuffing and physical layer coding violations
   • Example framing for each technique
6. 7 Marks
   bExplain Go-Back-N ARQ and Selective Repeat ARQ protocols with suitable examples.
   How to answer

   • Principle of sliding window with cumulative ACK and selective ACK
   • Go-Back-N operation: window, timeout, retransmit all from error with example
   • Selective Repeat operation: buffering, NAK, individual retransmission with example
   • Efficiency and comparison summary
7. 7 Marks
   aDescribe flow control techniques. Compare Stop-and Wait and Sliding Window Protocols.
   How to answer

   • Need for flow control and feedback vs rate-based techniques
   • Stop-and-Wait operation, efficiency and diagram
   • Sliding Window operation with sender/receiver windows
   • Comparison table on utilization, complexity, implementation
8. 7 Marks
   bExplain MAC addressing and Binary Exponential Backoff (BEB) algorithm.
   How to answer

   • MAC address format: 48-bit OUI and NIC specific, unicast/multicast/broadcast
   • Need for MAC addressing in LAN delivery
   • BEB steps: sense, transmit, collision detect, random backoff doubling
   • Example of backoff after i-th collision
9. 7 Marks
   aCompare CSMA/CD and CSMA/CA protocols.
   How to answer

   • Principle of carrier sensing and persistence
   • CSMA/CD: collision detection, jam, backoff, wired LAN use
   • CSMA/CA: RTS/CTS, NAV, collision avoidance for wireless
   • Comparison on detection vs avoidance, efficiency, application
10. 7 Marks
    bDescribe IEEE 802 LAN standards and explain the architecture of Local Area Networks.
    How to answer

    • Overview of IEEE 802 family: 802.3 Ethernet, 802.11 WLAN, 802.15 etc.
    • LLC and MAC sublayers role
    • LAN architecture: topology, medium, access method
    • Frame format and services example
11. 7 Marks
    aExplain the functions of the Network Layer and discuss different switching techniques.
    How to answer

    • Network layer services: routing, addressing, packetizing, congestion control
    • Circuit vs packet switching and datagram vs virtual circuit
    • Message switching characteristics
    • Comparison of delay, cost, suitability
12. 7 Marks
    bDescribe Bellman-Ford routing algorithm and compare it with Dijkstra's algorithm.
    How to answer

    • Bellman-Ford distance-vector steps and relaxation formula
    • Dijkstra greedy shortest path steps
    • Comparison on negative weights, complexity, distributed vs centralized
    • Example iteration and count-to-infinity issue
13. 7 Marks
    aCompare IPv4 and IPv6 protocols highlighting their advantages and limitations.
    How to answer

    • IPv4 header, 32-bit addressing and exhaustion issue
    • IPv6 header, 128-bit addressing, extension headers
    • Comparison table: address size, header, QoS, security, fragmentation
    • Advantages/limitations of each
14. 7 Marks
    bExplain the services and functions of the Transport Layer.
    How to answer

    • End-to-end services: multiplexing, connection management, reliability
    • Functions: segmentation, flow/error control, addressing ports
    • TCP vs UDP service models
    • Relation to application and network layers
15. 7 Marks
    aDiscuss congestion control and flow control mechanisms used in TCP.
    How to answer

    • Flow control via sliding window and receiver advertised window
    • Congestion control phases: slow start, congestion avoidance, fast retransmit/recovery
    • Difference between flow vs congestion control
    • cwnd vs rwnd and Tahoe/Reno behavior
16. 7 Marks
    bExplain the architecture and working of the Simple Network Management Protocol (SNMP).
    How to answer

    • Components: manager, agent, MIB, SMI
    • SNMP operations: Get, Set, Trap, Inform
    • Architecture diagram manager-agent interaction over UDP
    • Versions and working example polling