2: Operating SystemsNetworking for Home & Small Business

Purpose of the OS

• Allows components to work together

• Write a report & print– Enter on keyboard– Stored in RAM– Processed by CPU– Displayed on monitor– Printed on printer

• All computerized device require an OS

How the OS Works• Loads OS into RAM from disk drive • Shell

– Interface with the applications & user– Provides access to the OS

• Interact with the shell using– Command Line Interface (CLI) – Graphical User Interface (GUI)

• Kernel– OS code that interacts with the computer hardware is

known as the– Manages communication between hardware &

software

The OS

CLI

GUI

The OS

• Manage one user at a time

• Multitask– OS keeps track of resources used

• Some resources are not directly connected to the PC– Examples???

Redirector & NOS

• Redirector (OS driver or Network Client software)• Now becomes a NOS

– Allows device to be shared– Acts as though it were directly connected

Review so far…

• Which interface has a command prompt?– CLI

• After powering up, the OS gets loaded into where?– RAM

• What interfaces with the user & application?– Shell

OS License

• Commercial License• Windows, Mac, UNIX

• GNU Public License (GPL)– FREE

• Linux

Comparing Licenses

Commercial License

GPL

Access Restricts/limits access to code

Access to code & can enhance it

Cost Expensive $$$

Windows, Mac, Unix; license each PC

Free

Development Cycle

Structured; changes aren’t avail quickly

Ongoing, changes distributed quickly

Support Avail for a fee usually

Mostly community support

OS Requirements

• Amount of RAM

• Hard disk space required

• Processor type and speed

• Video resolution

• Minimum– Poor performance

• Recommended

Activity- Commercial or GPL

Choosing An OS

• Must meet requirements of user– Support applications– Security sufficient

• Is the hardware supported by the OS?

• Will the company support the new OS?

• At home, will support be available readily?

• Total Cost of Ownership (TCO)– Buying, installing, supporting

Review

1. Which type of OS provides full access to the source code?

– GPL

2. Which type of OS is costly?– Commercial

3. Which type of OS provides support through its users?

– GPL

Review

1. Name 4 specifications for OS install requirements.

– HD– Processor– RAM– Video Resolution

2. Describe a network redirector.3. What are the 2 ways you can interact with

the shell?– CLI & GUI

Lab 2.2

• Specifications of OS

Installing the OS- Clean Install

• Deletes all data on install path• Applications need to be reinstalled• When would you do a clean install?

Installing the OS- Upgrade

• System config settings, applications and data are preserved

• Replaces old OS files with new ones

Installing the OS- Multi-boot

• Can install more than one OS to a drive• Why?• Each has its own partition

– Own files & config settings

• On start, user chooses which OS• Only one OS runs at a time

Activity

Pre-Installation Checklist1. Verify all hardware is certified to work with the OS.

2. Verify the hardware resources meet or exceed the minimum requirements.

3. Confirm the appropriate installation medium is available. Do you have CD or DVD & the correct drive?

4. If the OS is to be installed on a system that already contains data: (a) Use system diagnostic tools and utilities to ensure the current OS installation is in good condition, free of malicious or damaging files and codes; (b) Complete a full backup of all important files.

5. If performing a clean-install, verify that all application software is available for installation.

Partitions

• On clean install, some techs…– Partition 1 for OS– Partition 2 for data

• When upgrade OS, data will not be deleted

Review so far…

1. What is a partition?

2. What happens to data on a HD during a clean install?

3. How many OS’s are running in a multiboot system?

4. What happens to applications during an upgrade?

Configure for Network• What is a network?

– Group of devices connected to each other to share info & resources

• NIC• IP Address

– Id’s computer UNIQUE• Subnet Mask

– Id’s the network it is on• Default Gateway

– the way out of the network

Network Communication

Configuring the IP

• Manual (static) or Dynamic (automatic) pool

Computer Naming

• Manually assigned

• For easy sharing

• Admin designs naming scheme

• PRT-CL-Eng-01 represents the 1st color laser printer in the Engineering Department

Planning Names & Addresses

• The larger the network gets, you MUST be organized & documented!

• Come up with guidelines

Review

1. A DHCP server assigns address how?– Automatically/Dynamically

2. What are 3 settings you need to connect to a network?

– IP, Subnet Mask, Default Gateway

3. What is a default gateway?– Address to get out of the network so it can

communicate with other networks

4. Describe a partition.

Review

1. Which install method requires applications to be reinstalled?

– Clean Install

2. Before upgrading the OS, what should you do with your data?

– Back it up

3. To be on a network, what 2 things need to be unique?

– IP address & computer name

When to Apply Patches

• What’s a patch?– Piece of program code

that can correct a problem or enhance the functionality of an application program or OS

• Update computers often BUT make sure you understand the patch first!

Applying the OS Patch

• Automatic installation

• Prompt for Permission

• Manual

Auto, Manual, or Prompt?

Applying the Application Patch

• Browsers, Office, other programs

• Repair a detected vulnerability or other problem

• Found on manufacturer’s site

Lab 2.3.3

Review

1. What’s a patch?

2. Where can you find a patch?• Manufacturer’s web site

3. What are the 3 methods for getting OS updates?

• Auto, Manual, With Permission

4. What user interface has icons?• GUI

Review

1. Where do devices get IP addresses from dynamically?

– A DHCP server

2. What is needed to install two OS’s on a PC?

– Multiple partitions

3. What letter grade will you get on this test?– A or B, hopefully

2: Operating SystemsNetworking for Home & Small Business