CPT304: Summary Blog Post: Operating Systems Review

 Summary Blog Post: Operating Systems Review

Kenneth Hodges

University of Arizona Global Campus

CPT304: Operating Systems Theory and Design

Dr. Joshua D. Reichard

January 30, 2022


Summary Blog Post: Operating Systems Review

Blog posts are a new concept, especially when this entire course has been formally written papers and discussions from the beginning. Operating systems and how they behave have been a mystery for me during my career in Information Technology, so what is one new thing to learn. This blog summary will entail a review of this course over the past five weeks and my growth within it.

Features of Contemporary Operating Systems and Their Structures

Operating systems vary to perform specific tasks based on the user's needs. However, they have very similar features and structures for the most part. As Silberschatz et al. (2014, p. 6) discussed, there is no universally understood definition of an operating system. Still, it is understood as the one program constantly running on a computer system. The features of an operating system vary by manufacturer, but essentially all operating systems include process management, memory management, storage management, protection, and security (see Appendix A for more detail). Based on the operating system in question, these features are provided to a lesser or greater degree.

Process Management

Process management is the system's method to share and exchange information to enable processes to operate. Process management is responsible for breaking down program requests into requested processes and managing them into the computer's various parts. Those processes are divided into four essential components while in memory: stack, heap, text, and data (Operating System – Processes, 2021). These processes move through different states to execute in the computer system until the program is complete. The cycles the processes move through are new, running, waiting, ready, and terminated (see appendix B for enhanced detail).

Memory Management

            Memory management is also the operating system's responsibility and entails the use of physical memory and virtual memory. Memory management is necessary to track memory spaces used by processes, properly utilize the computer's memory resources, maintain data integrity, and allocate and deallocate memory during execution (Choudhary, 2021). Memory management uses main memory and virtual memory to accommodate the user-mode processes and kernel mode operating system functions (Silberschatz et al. 2014, p. 328). Memory management utilizes several techniques such as static and dynamic loading, static and dynamic linking, and swapping to provide the most efficient use of main memory, cache, and virtual memory. To keep the processor operating at maximum efficiency, the use of virtual memory allows the use of space outside the main memory and cache to keep processes in a ready state to process. This virtual memory is generally in a reserved portion of a physical disk installed on the computer that the operating system creates to accommodate virtual memory space. (see Appendix C for additional detail)

I/O, Files and Mass Storage

In modern computer systems, files, mass storage, and I/O are all one part of two essential roles a computer system is designed to perform (Silberschatz et al., 2014, p. 561). Depending on the reason why you or your organization deploy computer systems, it may be the most critical role. Mass storage (namely disk drives) is considered secondary storage system on most computing systems. There are many various storage types out on the market, such as hard drives, solid-state drives, flash drives, and data tape, to name a few. The modern operating system is tasked with managing communications with all of them. Communication between the computer system and the devices is accomplished mainly by device drivers. The device's manufacturer usually supplies these device drivers, but some can use the drivers provided with the operating system.

These various storage systems communicate along wires called the I/O bus system inside the computer (Silberschatz et al., 2014, p. 443). The bus system communicates directly with the USB, serial, parallel ports, various device controllers inside the computer to send and receive signals from the various storage and I/O devices connected to the computer. (see Appendix D for more detail).

The operating system handles files located on the previously mentioned storages devices with a controlled file system of tree-like directories and subdirectories located from a root (commonly a disk identified with a letter in Windows systems such as C: drive or D: drive). The operating system's role is to track the logical file onto a physical disk by creating and maintaining a volume table (Silberschatz et al., 2014, p. 512).

Protection and Security

The protection and security of computer systems to control the access of programs and users to the resources are multi-dimensional. Protection is a term used to describe the way the computer system regulates who can log on, access files, use I/O devices and determine the level of access in each of these circumstances. The protection of the internal systems to assure that people, devices, systems calls, programs are provided the least access possible to do the tasks they are supposed to is called the principle of least privilege (Silberschatz et al., 2014, p. 602). The operating system uses techniques like segmenting domains, access matrix (capability lists and access lists), and access control to accomplish this protection.

The most common protection is the access matrix to control access to files, processes, programs, devices, and domains. These lists can provide pinpoint access to the smallest of resources or open up the system to widespread usage. These techniques are deployed to follow the common theme with protection; provide the least access possible to accomplish the task. (see appendix E for greater detail)

Security is more concerned with external factors such as access to the computer system, network access, building access, etc. (TechDifferences, 2019). Security systems will be more complex because it deals with all external threats from access via keypad or card swipe to a building or room to the login process to a protected computer system. Security systems manage threats of all types.  

The degree plan I have chosen is Cybersecurity and Data Management, and to me, this course lays the foundation for understanding and comprehension of my future courses. Understanding the operating system is of paramount importance to being competent to discuss future courses and roles in cybersecurity. Even someone in compliance management would need a fundamental understanding of the operating system to fully embrace the role and be a competent advocate for their respective company. My personal experience with operating systems has been limited to Microsoft Windows-based products, but in the future, I endeavor to better understand other operating systems for a complete picture. Thank you, Dr. Reichard.              

             


 

 

References

Choudhary, V. (2021). Memory management in operating system. GeeksforGeeks. Retrieved January 30, 2022, from https://www.geeksforgeeks.org/memory-management-in-operating-system/

Silberschatz, A., Galvin, P. B., & Gagne, G. (2014). Operating system concepts essentials (2nd ed.). Retrieved from https://redshelf.com/

TechDifferences. (2019). Difference between security and protection (with comparison chart). Difference Between Security and Protection. Retrieved January 30, 2022, from https://techdifferences.com/difference-between-security-and-protection.html

tutorialspoint.com. (2021). Operating System - Processes. Operating system - processes. Retrieved January 30, 2022, from https://www.tutorialspoint.com/operating_system/os_processes.htm


 


Appendix A

Operating System Main Features



 

Appendix B

Process States



 

Appendix C

Memory Management


Appendix D

Storage Management

 


Appendix E

Protection Management


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