Jawaharlal Nehru Technological University Hyderabad B.Tech IV Year DISTRIBUTED SYSTEMS Previous Question Paper (September - 2022 - R18)

Modern distributed systems are evolving rapidly to meet the demands of global connectivity and massive data processing. The key trends shaping this domain include:

• Ubiquitous Networking and Wireless Connectivity: The proliferation of high-speed mobile networks (5G) and IoT devices has transformed distributed systems from static, wired environments to highly dynamic, mobile-first architectures.
• Cloud Computing and Virtualization: The shift toward Infrastructure as a Service (IaaS) and Platform as a Service (PaaS) allows for elastic resource provisioning. Virtualization and containerization (e.g., Docker, Kubernetes) have become standard for deploying microservices, enabling efficient resource utilization and isolation.
• Edge and Fog Computing: To reduce latency and bandwidth consumption, processing is moving closer to the data source. Edge computing processes data at the network edge, while Fog computing extends cloud capabilities to the local network level.
• Big Data and Distributed Analytics: Systems are designed to handle massive datasets using frameworks like Apache Spark and Hadoop, which rely on distributed storage (HDFS) and parallel processing models.
• Serverless Computing: This trend abstracts away server management entirely, where developers focus on function-level code execution triggered by events, leading to highly cost-effective and scalable architectures.

The architectural model of a distributed system defines how components are organized and how they interact to achieve system goals. The primary models are:

• Software Architecture: This focuses on how software components are structured. Common styles include:
  1. Layered Architecture: Components are organized into layers, where each layer provides services to the one above it.
  2. Object-based Architecture: The system is viewed as a collection of objects that interact through method invocations.
  3. Data-centered Architecture: Components communicate through a shared repository or database.
  4. Event-based Architecture: Components communicate via the propagation of events, promoting loose coupling.
• System Architecture: This describes the placement of software components on physical hardware. Key models include:
  1. Client-Server Model: The most common model where clients request services and servers provide them. It can be extended to multi-tier architectures (e.g., 3-tier: presentation, application, and data layers).
  2. Peer-to-Peer (P2P) Model: All nodes act as both clients and servers, distributing the workload and eliminating single points of failure.
• Fundamental Interaction Model: This considers the communication patterns, specifically:
  Synchronous vs. Asynchronous Communication

  Synchronous systems assume bounded delays for processing and message delivery, whereas asynchronous systems make no such assumptions, which is more realistic for wide-area networks.