Unit 211: Operating Systems Fundamentals and Advanced Concepts

1. Introduction to Operating Systems

• Definition and purpose of Operating Systems (OS)
• Key functions of OS: resource management, user interface, and system services
• Types of Operating Systems: batch, time-sharing, distributed, real-time, embedded
• Evolution of Operating Systems: from early systems to modern OS

2. Operating System Structures

• Overview of OS architecture
• Monolithic Systems
  • Characteristics
  • Advantages and disadvantages
• Layered Systems
  • Concept and implementation
  • Benefits and challenges
• Microkernel Systems
  • Design principles
  • Communication mechanisms
• Hybrid Systems
  • Combination of microkernel and monolithic features
  • Examples

3. Process Management

• Definition of processes and threads
• Process states and lifecycle
• Process scheduling algorithms
  • First-Come-First-Served (FCFS)
  • Shortest Job Next (SJN)
  • Priority Scheduling
  • Round Robin
  • Multilevel Queue
• Process synchronization
  • Critical section problem
  • Semaphores and mutexes
  • Classic synchronization problems (e.g., Producer-Consumer)
• Deadlock
  • Conditions for deadlock
  • Deadlock prevention, avoidance, detection, and recovery

4. Memory Management

• Memory hierarchy overview
• Contiguous memory allocation
• Paging
  • Concept and structure
  • Page tables and address translation
• Segmentation
  • Segments and segment tables
• Virtual Memory
  • Principles and benefits
  • Page replacement algorithms (FIFO, LRU, Optimal)
• Memory allocation strategies
  • Fixed and dynamic partitioning
  • Buddy system
  • Slab allocation

5. File Systems

• File concepts and attributes
• File operations (create, delete, read, write, append)
• Directory structures
  • Single-level, two-level, tree-structured directories
  • Access paths
• File system mounting and unmounting
• File access methods
• Access control mechanisms
  • Permissions and protection
  • Access Control Lists (ACL)

6. Input/Output Management

• I/O devices and their characteristics
• Device drivers
• I/O techniques
  • Programmed I/O
  • Interrupt-driven I/O
  • Direct Memory Access (DMA)
• Buffering
  • Single and double buffering
• Error detection and handling in I/O

7. Security and Protection

• Importance of security in OS
• Access control models
• Authentication techniques
• Encryption basics
• Common security threats
  • Viruses, worms, trojans
  • Denial of Service attacks
  • Privilege escalation

8. Distributed Operating Systems

• Definition and characteristics
• Network protocols relevant to distributed OS
• Distributed file systems
• Communication models
  • Message passing
  • Remote Procedure Calls (RPC)
• Synchronization and consistency in distributed systems

9. Real-time Operating Systems (RTOS)

• Features of RTOS
• Types: hard vs soft real-time
• Scheduling algorithms in RTOS
  • Rate Monotonic Scheduling (RMS)
  • Earliest Deadline First (EDF)
• Applications in embedded systems and critical environments

10. Case Studies and Modern Trends

• Case studies
  • Windows OS architecture overview
  • Unix/Linux OS design and features
  • macOS overview
• Emerging trends
  • Virtualization technologies
  • Containerization (Docker, Kubernetes)
  • Cloud computing and OS role
  • Mobile OS developments