Transcript Intro to the AS/400 - Florida State College

Intro to Info Tech
Systems S/W
This presentation can be viewed on line at:
http://web.fscj.edu/Janson/cgs1060/wk01.SystemsSW.ppt
Copyright 2003
by Janson Industries
1
Objectives

Explain 2 types
 Operating
Systems
 The
general purpose of
 Specific tasks of
 Utility
Programs
 Types
of
2
Copyright 2014 by Janson Industries
Operating System

Set of programs that:
 Enable
h/w to function
 Provide a user interface
 Manage system resources
 Configure
devices
 Schedule jobs
 Monitor:
• Performance
• Memory
• Applications
 Provide
security
3
Copyright 2014 by Janson Industries
Operating System

Set of programs that:
 Enable
users to run applications
 Provide
common functions for
applications
 Printing
 Saving
and retrieving files
• This is how OS came about
 Establish
Internet connections
4
Copyright 2014 by Janson Industries
Operating Systems

PCs use Windows, Linux, or OSX
(Macs)
 Some



computers can run multiple
Midrange and mainframes use
different OS
OS also called a platform:
Applications written for specific
platforms
 Must
buy correct application for
your platform
5
Copyright 2014 by Janson Industries
OS Functions

Booting: starting the computer
 Cold
boot: powering on the computer
 Warm boot: restarting

When installing new applications,
often must reboot (warm boot)

OS programs stored on hard drive

When booting:
 Kernel
loaded into main memory
 Kernel
comprised of those programs
that provide basic OS functions
 Remains in MM
6
Copyright 2014 by Janson Industries
OS Interfaces


Interface is the way users can enter
data and instructions and how
information is displayed
Two types:
 Command
Line Interface (CLI)
 Graphical User Interface (GUI)


Command line requires commands
and syntax
GUI is point and click
7
Copyright 2014 by Janson Industries
Command line
Entered command
and pressed Enter
Copyright 2014 by Janson Industries
GUI
Clicked on icons
8
OS Categories


Identified by how many tasks and
users it can support simultaneously
Single user/single task
 Smaller
devices only allow one user
to run one application at a time

Single user/multi-tasking
 Can
run many apps at the same time
 Only one app is active
9
Copyright 2014 by Janson Industries
OS Categories

Multi-user
 Many
users can run many apps at
the same time
 Larger
computers
 Networks

Multi-processor
 Supports
many CPUs and many
active jobs
 Many
apps can be running
simultaneously
10
Copyright 2014 by Janson Industries
OS

Manages MM
 OS
assigns memory to applications
 When apps done, releases memory

Sometimes apps too big for RAM

Solution: Virtual Memory
 App
broken up into pages (pieces)
 Pages loaded into MM as needed
 Removed when not needed
11
Copyright 2014 by Janson Industries
OS

Also sets up and manages buffers
 Memory

that acts as a waiting area
Classic example: print buffer
 Printer
slow compared to CPU
 Instead of CPU waiting for printer to
accept next print job
 Output sent to buffer
 When printer ready
 Output retrieved from buffer and sent
to printer

This process is called SPOOLing
 Simultaneous
On Line
Copyright 2014 by Janson Industries
Peripheral Operations
12
13
Copyright 2014 by Janson Industries

Set up date/time to run an app
Where to store
What to store
When to store
14
Copyright 2014 by Janson Industries
Scheduling Jobs

In multi-user environment OS will
allow priorities to be assigned
 By
user
 CEO
 By
has highest priority
type of job
 Print
job higher than browsing web
 Availability
 External
of resources
storage busy
15
Copyright 2014 by Janson Industries
Configuring Devices




Each device has its own commands
OS contains "drivers" (programs) to
communicate with the most common
devices
Drivers loaded into MM when
computer started
If OS doesn't have driver, you may
have to install the driver
 Usually
comes with device or easily
downloaded from the Web
16
Copyright 2014 by Janson Industries
Monitor Performance

CPU utilization
17
Copyright 2014 by Janson Industries
Can see multiple
resources at a time
Copyright 2014 by Janson Industries
18
Monitor Performance

Disk space used/available
19
Copyright 2014 by Janson Industries
Monitor Performance

App/process
monitoring
20
Copyright 2014 by Janson Industries
Monitor Performance


Disk fragmentation
Analyses first, then, if needed, defrag
21
Copyright 2014 by Janson Industries
File Management

Organize in folders

Copy

Delete

Search
Search particularly helpful when
you forgot where you saved it or
what you named it
Copyright 2014 by Janson Industries
22
File Management

Disk scanner
 Looks
for unused/temp files
 Looks
for uncompressed files
 Lets
you easily delete and
compress them
23
Copyright 2014 by Janson Industries

Uninstaller
 Easily
remove an app
24
Copyright 2014 by Janson Industries
Security

Create Userids and Passwords
 Force
users to log on to the computer
 Enforce

at file and application level
Keeps track of incorrect log on
attempts
 May
disable Userid after a certain
number of incorrect attempts

Keeps track of unauthorized attempts
to access files and apps
25
Copyright 2014 by Janson Industries
Security

Most provide some firewall
 Protects
computer from unauthorized
access
 I.e.
you download a web page that
contains a program that looks through
hard drive and email for
• Credit Card numbers
• SSN
• Bank Statements


Copyright 2014 by Janson Industries
Some anti-virus protection
Usually need utility programs for
better/most up to date security
26
Lots of OS

Handheld – Palm, Symbian
(Nokia), Blackberry OS, Android,
iPhone, Windows Phone 7

PC – Windows, OS X, Linux

Midrange – Solaris, IBM i, Linux

Mainframe – MVS, VM, Unix, Linux

Most are proprietary, Linux and
Android are open source
 Said
another way: most you must
pay for, open source is free
Copyright 2014 by Janson Industries
27
Open Source vs. Closed Source

Open source price is better - pro

But if everyone can see source code
 Greater
security risk - con
 More eyes to catch errors - pro
 More programmers can work on to
improve - pro

But if not paid for it, what's the
incentive to build/maintain open
source s/w? - con
28
Copyright 2014 by Janson Industries
Utility Programs

S/W that enables the computer to
work better
 Example:
www.inksaver.com
 Potential
75% decrease in ink used
 Would you pay $32 for that?


MS continually crams more into OS
that was handled by stand alone utils
However, stand alones usually do a
better job than those utilities included
in Windows
 Can
buy
 Often a free version available online
Copyright 2014 by Janson Industries
29
Utility Programs Types

Antivirus
 Virus:
s/w that will harm or impede
your computers applications and data
 Some
harmless: Yankee Doodle
 Some not: Michaelangelo

Two types:
– replicate themselves
 Trojan horse – hidden in other s/w,
email, etc.
 Worms
30
Copyright 2014 by Janson Industries
Utility Programs Types

Spyware and Spyware removers
 You
may want to install
 Websites will install without permission
 Spyware
removers usually also remove
adware

Internet filters
 Antispam:
usually included in email app
(MS Outlook) or by email provider
 Web filter: usually included in browser
(MS IE, Firefox, Chrome, etc.)
 Pop up blocker: usually included in
browser
31
Copyright 2014 by Janson Industries
Utility Programs Types

File compression: zip and unzip files to
save space on drives
 OS
will often do automatically
 PKZIP, WinZip

File conversion
 WAV
to MP3, Word to PDF, Access to
Excel

Media Players
 Why
not just use Media Player?
 Can it access your iPod?
 Need iTunes
Copyright 2014 by Janson Industries
32
Points to Remember
Operating Systems enable the
computer hardware to work

Provides a GUI and commands to
perform system functions

Enable the h/w and applications to
function

For classroom based classes:
Bring your thumb drive to the next class
33
Copyright 2014 by Janson Industries