Distributed Systems

Distributed Systems is a field of computer science that studies collections of autonomous computing elements that appear to their users as a single coherent system. These systems, connected by a network, communicate and coordinate their actions by passing messages to achieve a common goal, such as sharing resources, improving performance, or providing fault tolerance. The core challenges in this domain involve managing concurrency, overcoming the lack of a global clock, and handling partial failures, all of which are fundamental to building the scalable and resilient infrastructure that powers the internet, cloud computing, and large-scale data processing.

1. Introduction to Distributed Systems
   1. Defining a Distributed System
      1. Basic Definition
      2. Key Components
      3. System Boundaries
   2. Characteristics of Distributed Systems
      1. Resource Sharing
      2. Openness
      3. Concurrency
      4. Scalability
      5. Fault Tolerance
      6. Transparency
   3. Comparison with Centralized Systems
      1. Architectural Differences
      2. Performance Trade-offs
      3. Complexity Considerations
   4. Examples of Distributed Systems
      1. Internet and World Wide Web
      2. Cloud Computing Platforms
      3. Peer-to-Peer Networks
      4. Distributed Databases
      5. Mobile Computing Systems
   5. Goals of Distributed Systems
      1. Resource Sharing
         1. Hardware Resource Sharing
         2. Software Resource Sharing
         3. Data Sharing
      2. Openness and Extensibility
         1. Open Standards
         2. Interoperability
         3. Extensibility Mechanisms
      3. Scalability
         1. Size Scalability
         2. Geographical Scalability
         3. Administrative Scalability
      4. Transparency
         1. Definition of Transparency
         2. Importance of Transparency
   6. Core Challenges
      1. Heterogeneity
         1. Hardware Heterogeneity
         2. Software Heterogeneity
         3. Network Heterogeneity
         4. Data Format Heterogeneity
      2. Concurrency
         1. Managing Concurrent Access
         2. Synchronization Issues
         3. Race Conditions
      3. Lack of a Global Clock
         1. Implications for Coordination
         2. Event Ordering Challenges
         3. Timing Dependencies
      4. Partial Failures
         1. Types of Partial Failures
         2. Impact on System Reliability
         3. Failure Detection Challenges
      5. Security
         1. Threats in Distributed Systems
         2. Security Requirements
         3. Trust Management
   7. Types of Transparency
      1. Access Transparency
      2. Location Transparency
      3. Migration Transparency
      4. Replication Transparency
      5. Concurrency Transparency
      6. Failure Transparency
      7. Performance Transparency
      8. Scaling Transparency
   8. Historical Context and Evolution
      1. Early Distributed Systems
      2. Evolution of Networking Technologies
      3. Milestones in Distributed Computing
      4. Current Trends
      5. Future Directions