Introduction to hardware and networking Module hardware and networking1.1

What is a computer? A programmable electronic device that can process, store and retrieve data Module hardware and networking1.2

Types of computer Microcomputers (or personal computers) – Desktop (single location) – Laptop or Notebook (mobile) – Tablet (mobile, touch screen, stylus) – Netbook (smaller mobile) – Personal Digital Assistant/Smart Phones (handheld) Module hardware and networking1.3

Functional classification Server – Primary task is storing and retrieving large quantities of data (network) Web server, servers in each office Workstation – High end-computer designed to be used by one person Office desktops Module hardware and networking1..4

About Hardware Hardware is any physical piece of equipment, called a device, that is both connected to your computer and controlled by your computer Comprehensive term for all of the physical parts of the computer. Refers to objects you can touch, like disks, disk drives, display screens, keyboard, printers and chips. Internal devices are placed inside the case of the computer External devices remain outside the case of the computer Module hardware and networking1.5

About software Exists as ideas, concepts, and symbols Provides instructions for the hardware to accomplish tasks. Can not be touched like the hardware. All parts are inside the computer. Module hardware and networking1.6

System unit power supply ports drive bays processor memory sound card video card modem card network card Module hardware and networking1.7

Interface between computers and devices Module hardware and networking1.8

Inside the PC processor chip adapter cards memory chips memory slots motherboard Expansion slots for adapter cards Module hardware and networking1.9

Printers Types of printer – Laser, inkjet (ink dispersion), solid ink, thermal printers, and impact printers Module hardware and networking1.10

Laser printer Uses mechanical, electrical, and optical technologies Capable of handling and printing large volumes quickly and continuously Module hardware and networking1.11

Dot matrix printers Overview of dot matrix printer technology: – Lesser quality of other printers – A print head moves across the width of the paper – Pins are used to print a matrix of dots on the page Can print multicopy documents and Last Forever Pins shoot against a cloth ribbon. Ribbon is used for ink and to lubricate Ribbon impacts the paper, depositing the ink Module hardware and networking1.12

Inkjet printers Overview of inkjet printer technology: – With Inkjet, ink is applied to paper using a matrix of small dots Plates with magnetic charge direct path to the page – Older inkjets have lower resolution, but today’s are photo quality – Images smudge on inexpensive paper Especially with higher resolution (wet paper) – Usually cost less Print color inexpensively Module hardware and networking1.13

Thermal printers Overview of thermal printer technology – Nonimpact printers that use heat to produce output – Popular in retail for bar codes and price tags – Wax-based ink heated by heat pins – Print head is as wide as paper, so does not move – Heat pins melt ink onto paper Module hardware and networking1.14

Networking - Basics Network defined The difference between Standalone and networked Systems Advantages of networking Disadvantages of networking Why use network – To share information – To Share hardware and software – Centralizing administration Module hardware and networking1.15

Types of networks Classification based on geographical area – LAN – WAN Module hardware and networking1.16

Network configuration Classification based on how computers behave in a network Two classifications are – Peer-to-Peer network – Server based network Module hardware and networking1.17

Server based network Designated computer to administer Resources centralized Supports larger networks Strong security Expensive Module hardware and networking1.18

Topologies - Physical Refers to physical arrangement of – Computers – Cables – Other components Module hardware and networking1.19

Star topology Connected to a central hub Easier administration Difficult to install High cable cost Hub failure fails the network Module hardware and networking1.20

Star bus topology Combination of several stars Augments systems in network Failure of hub/s fails the network Module hardware and networking1.21

Network hardware Hub Cables Connectors Switches Routers Module hardware and networking1.22

Hub Standard component in Star topology Types – Active, Passive – Manageable Easier administration Centralized monitoring of network Module hardware and networking1.23

Cables Wires the LAN, usually Transmit signals through network Different cable considerations according to need Types – Co-axial – Twisted Pair – Fiber-optic Module hardware and networking1.24

Twisted pair Pair of insulated copper wires Types – Shielded(STP) – Unshielded(UTP) UTP common in LAN Max. cable length – 100 meters Module hardware and networking1.25

Connectors for UTP RJ – 11 and RJ – 45 RJ11 in telephone cables – 4 cable connections RJ45 in LAN cables – 8 cable connections Module hardware and networking1.26

Cable connection method Used to connect a system to hub or switch in LAN Module hardware and networking1.27

Network operating systems Co-ordinates hardware and software Ties together all computers and peripherals Provides security by controlling access to resources and peripherals shared Manages users Example – Windows 2003 and Windows 2008 server operating systems Module hardware and networking1.28

Postmaster’s role in managing windows network Ensure that the administrator’s account is not known to all users in the office Ensure that ordinary users are not logging in with administrative rights Ensure that one user with account operator right in the server is created for PM or one of the supervisors – helps in creating users in the absence of administrator Ensure that server is protected physically Module hardware and networking1.29

Password Security Do not allow blank passwords Assign a Password for the Administrator Account Determine who has Control over Passwords Educate Users on How to Use Passwords – Avoid obvious associations, such as a family name – Use long passwords – Use a combination of uppercase and lowercase characters Module hardware and networking1.30

User level security in domain Module hardware and networking1..31 Set logon hours according to requirements Set expiration for User accounts Specify the Computers from Which a User Can Log On – Domain users can log on at any computer in the domain, by default – Domain users can be restricted to specific computers to increase security

Database management and SQL Server Overview of Databases – Data is a collection of raw facts – Database is a collection of data stored inside tables – Provides centralized control of data – Relational database management Advantages – Reduces data redundancy – Can be shared among many users – Security around access can be implemented Examples – SQL 2000 and SQL 2005 Module hardware and networking1.32

Administrative tasks in SQL Server SQL Server enterprise manager (SQL 2000) and SQL Server management studio (SQL 2005 /2008) are used to perform admin tasks The admin tasks involved are – Manage security – Manage databases – Manage backups – Follow up events Module hardware and networking1.33

Backup of database - Overview Backup is a copy Stores copy in another media like – Local Hard disk – Tape disk, DVD, CD, external hard disk – Network drive Helps recover data in case of failure and also to recall past data for investigation or auditing Module hardware and networking1.34

Backup types Full or complete Differential Transaction log Module hardware and networking1.35

Backup strategy Good strategy helps restore data with minimum down time Minimizes permanent loss of data A good plan should involve minimum shut down of operations for backup Good strategy should put the system back to what it was before failure Good protection should exist for the backup media – preferably stored offsite Module hardware and networking1.36

Security in SQL Server Strong password for sa Password for the sa secured by divisional head Postmaster to ensure that unauthorised administrative access to admin tools is prevented Module hardware and networking1.37