1. OS - System security 시스템 보안

1. Operating System

1.OS : Throughput, Realiability, Availability, Turn around time

(1) Main function of operating system

   ① Process management
   ② Primary memory management
   ③ Auxiliary memory management
   ④ Input / Output System Management
   ⑤ File System  Management
   ⑥ Error Detection & Response

(2) Structure of Operating System

   Hardware - Processor - Memory - Process - Peripheral Equipment - File Management

(3) Technology Development Flow of Operating System

   Batch Processing System 

   Multi-Programming System, Time Sharing System, Multi-Processing System, Real Time Processing System

   Multi-Model Processing

   Distributed Processing System

2. The main construction techniques of OS

(1) Process Management

   Process, Thread

   PCB(process control block)

   New - Ready - Run - Wait - Exit

   Code, Data, Stack, Heap

   Process Scheduling

   Utilization, Throughput, Turnaround Time, Waiting Time, Response Time

   Preemptive Scheduling Policy, Non-Preemptive Scheduling Policy

   FIFO, SJF, Priority Scheduling, SRT, RR, Feedback

   Deadlock - Mutual Exclusion, Wait, Non-Preemption, Circular wait

      Solution - Prevention, Evasion, Detetion, Recovery

(2) Memory Management

   Type of memory

      Main Memory(Real Memory) - ROM, RAM, Fixed Partition, Variable Partition

      Virtual Memory - Paging, Segmentation, FIFO, LRU, OPT, Clock

      Auxiliary Memory(Secondary Memory)

   Method of Main memory management

      Fetch, Placement, Replacement, 

   Fragmentation

      Internal Fragmentation, External Fragmentation

      Solution - Compacting, Paging

(3) File System Management

   FAT(File Allocation Table), NTFS(NT file System), EXT2 - FSCK, EXT3 - Journaling

(4) Distributed System

   Transparency

3. The main functions and features of a case-by-case basis of the operating system

(1) Unix, Linux system

   Kernel, Shell(Bourne, C, Korn), File system(Tree, Boot, Super, Inode, Data)

(2) The feature of security operating system

   Authorization = Authentication + Access control