Week 3 Flashcards
Operating Systems
Secure Shell (SSH)
A protocol implemented by other programs to securely access one computer from another
Virtual Private Network (VPN)
Allows you to connect to a private network, like your work network, over the internet.
PuTTY
A free, open source software that you can use to make remote connections through several network protocols, including SSH.
Operating System
The whole package that manages our computer’s resources and lets us interact with it.
Two major components of an OS
Kernel space - the main core of an OS that talks to computer hardware and manages computer’s resources
User space - the stuff users interact with
What are three common Linux distributions?
Unintuitive, Debian, and Red Hat
Process Scheduler
Part of the kernel that allows for multitasking between multiple programs running at once
What does the I/O allow the kernel to do?
To talk to external components of the computer such as discs, keyboards, audio devices, etc.
What are the four main managements of the kernel of an OS?
File, process, memory, and I/O management
Block storage
Improves faster handling of data because the data isn’t stored as one long piece and can be accessed quicker.
Process
A program that’s executing, like our internet browser or text editor.
Time Slice
A very short interval of time that gets allocated to a process for CPU execution
The kernel and processes
Creates processes, efficiently schedules them, and manages how processes are terminated.
Virtual memory
The combination of hard drive space and RAM that acts like memory that our processes can use.
I/O Device
Devices that perform input and output
What is the usual issue with a slow machine?
Usually it’s some sort of hardware resource deficiency.
Shell
A program that interprets text commands and sends them to the OS to execute
Logs
Files that record system events on our computer, just like a system’s diary. Ex: They look like the event log in Analyst
BIOS /UEFI
A low-level software that initializes our computer’s hardware to make sure everything is good to go.
POST
Power On Self Test
Series of diagnostic tests the BIOS/UEFI does during the boot process to make sure computer is working okay.
Explain the boot process.
Power on -> POST -> Boot devices (hard drive, disc drives, USB drives) in order that is configured in the BIOS/UEFI -> Within the drive a bootloader is found -> Executes the bootloader to load the OS-> Kernel is loaded -> kernel loads drivers, resources, etc. -> system processes and the user space is launched
Bootloader
Small program that loads the operating system.
