RTU Kota B.Tech 6th Semester Distributed Systems Question Paper 2025 (CSE/IT)

RTU Distributed Systems 2025 Paper Review

Preparing for the Rajasthan Technical University B.Tech Distributed Systems exam requires a firm grasp of network coordination, concurrent processing, and fault tolerance. For Computer Science and Information Technology students building microservices or large-scale backend architectures, understanding how independent nodes agree on a shared state without a global clock is essential. You cannot design a highly available database or deploy a load-balanced API without understanding synchronization, data replication, and consistency models.

The 2025 paper tests your capability to trace logical clock timestamps, execute leader election algorithms, and analyze two-phase commit protocols. Publishing this specific 6th-semester paper review directly to exam-support.in provides engineering students exactly what they need to understand how examiners construct algorithmic problems and distribute marks across the network coordination modules. This targeted preparation strategy helps approach the exam confidently, Jaiprakash.

Understanding the Exam Pattern

The RTU theory examination is a three-hour paper worth 70 marks. The paper features three distinct sections designed to evaluate both foundational network definitions and complex synchronization execution.

• Part A: This section contains ten compulsory questions worth two marks each. You must define terms like network partition, state the difference between Remote Procedure Call (RPC) and Remote Method Invocation (RMI), explain access transparency, or define a cut in a global state under 30 words.
• Part B: You will find seven questions here. You must answer five of them. Each question is worth four marks. Your answers require explaining the Bully algorithm for elections, tracing Lamport's logical clock for a sequence of events, or detailing the two-phase locking protocol.
• Part C: This section offers five major questions. You need to answer three. Each question carries ten marks. These require you to calculate vector clock timestamps for a complex message-passing sequence, execute the Ricart-Agrawala mutual exclusion algorithm step-by-step, or design a complete distributed transaction sequence incorporating the atomic commit protocol and failure recovery.

Core Topics Evaluated in the Paper

The 2025 question paper covers several critical modules that establish the mathematical rules for independent node coordination. Focus your study time on these specific areas to maximize your score.

Time and Global States

This module evaluates your understanding of event ordering without a physical global clock. You must master Lamport's Logical Clocks and Vector Clocks. Practice calculating the exact timestamp vectors as messages pass between processes. You must know the mathematical update rule for a receiving process $P_i$ getting a message with timestamp $T_m$:

$$T_i = \max(T_i, T_m) + 1$$

Study the Chandy-Lamport algorithm used for recording a consistent global state or "snapshot" of the system.

Coordination and Agreement

Independent nodes must agree on shared resources and leadership. For distributed mutual exclusion, practice tracing the exact message requirements for the Token Ring algorithm and the Ricart-Agrawala algorithm. For election protocols, you must understand how the Bully algorithm handles a coordinator failure and traces the sequence of "Election," "OK," and "Coordinator" messages. Review the fundamental principles of consensus, specifically how nodes reach an agreement even when some processes fail.

Interprocess Communication and Remote Invocation

This module focuses on how nodes actually talk to each other. Study the mechanics of data marshalling and external data representation. You must understand the step-by-step execution of a Remote Procedure Call (RPC), from the client stub packing the parameters to the server stub unpacking and executing the function. Compare this with Java RMI, which handles distributed objects.

Distributed Transactions and Concurrency Control

When multiple nodes update a shared database, the system must maintain the ACID properties. Study the difference between flat and nested distributed transactions. The 2025 paper heavily features the Two-Phase Commit (2PC) protocol. You must trace the exact sequence of "CanCommit," "Yes/No," and "DoCommit" messages between the transaction coordinator and the participating nodes. Review optimistic concurrency control and timestamp ordering methods.

Distributed Deadlocks and Fault Tolerance

Distributed systems suffer from partial failures. You must know how to detect distributed deadlocks by drawing and analyzing global Wait-For Graphs. Study the edge-chasing algorithm. For fault tolerance, understand the mechanisms of data replication and how quorum-based protocols manage read and write conflicts across replicas.

Answer Writing Strategy for High Marks

RTU evaluators look for clean timing diagrams, explicit message sequences, and clearly calculated clock vectors. Use a blue pen for text explanations and calculation lines. Use a black pen and ruler for drawing process timelines, message arrows, and system architectures.

In Part A, answer directly. If a question asks for the definition of concurrency transparency, state clearly that it enables multiple users or processes to operate concurrently using shared information objects without interference between them.

In Part B, use clear graphical structures. When tracing Lamport's clock, draw horizontal lines for each process ($P_1, P_2, P_3$). Mark the local events clearly, draw diagonal arrows to represent messages sent between processes, and write the calculated integer timestamp directly above every single event dot.

In Part C, precision in execution is critical. When solving a ten-mark Two-Phase Commit problem, draw a vertical sequence diagram. Place the Coordinator on the left and the Participants on the right. Draw every message exchanged, explicitly noting the state changes (e.g., INIT, WAIT, COMMIT, ABORT) at each node as the timeline progresses downward. Draw a box around your final system state conclusion.

Time Management During the Exam

Allocate exactly 20 minutes to Part A. Spend 40 minutes addressing the five short-answer questions in Part B. Reserve the remaining 120 minutes for the three long-answer questions in Part C. Drawing multi-process timing diagrams, calculating large vector clock arrays, and tracing transaction states requires steady focus and significant writing time to prevent tracking mistakes. This distribution guarantees you 40 minutes per major question, giving you time to double-check your $\max()$ function calculations for message receipts. Use the final 10 minutes to verify your question numbering, ensure all message arrows have directional heads, and check that your wait-for graphs accurately reflect the resource locks.