Technology in Action Overview of Chapter 7 & 9
By Harbakshish Singh
Fundamentals of Networking
A computer network has two or more computers
They are connected via software and
hardware
Any device connected to
network is called node
There are two categories of
networks (LANs and
WANs)
Advantages of NetworksShare an Internet
connection
Share printers and other peripheral
devices
Share files and communicate
with computers
Avoid file duplication and
corruptionLower cost licensing
Centralized Administration
Conserve Resources
Disadvantages of Networks
Viruses Hacking Network failure
Slow serviceCostExpert
support required
Ways to classify Networks
PAN (A personal area
network)
LAN (A local area network)
HAN (A home area network)
MAN (A metropolitan area network)
WAN (A wide area network)
What are LayersPhysical
Layer
Data Link Layer
Network Layer
Transport Layer
Session Layer
Presentation Layer
Application Layer
Types of Layers and their use
Function of Layers
TCP/IP Model Consists of four layers
Link/Network Interface
Internet
Transport
Application
Example of TCP/IP
Types Home Networks
Ethernet networks are the most common networks used in home
networking.
Most Ethernet networks use a combination of wired and
wireless connections, depending on the data throughput required.
Wired connections usually achieve higher throughput than
wireless connections.
Wired Ethernet home networks use the gigabit Ethernet
standard.
Wireless Ethernet networks are identified by a protocol standard: 802.11 a/b/g/n.• 802.11n is the most current standard.
Connection-oriented vs. Connectionless Communication
• POP (Popular Post Office Protocol) used for sending email messages require email client and server verification
• VoIP (Voice over IP) used to make call without verifying first whether another device is there.
Example of Connection between e-mail client and server
Example of Connectionless communication
Components of Network
• A means of connecting the nodes on the net work (cables or wireless technology)• Special hardware devices that allow the
nodes to communicate with each other and to send data• Software that allows the network to run
Ways to Connect to Internet• Cable transmits data over coaxial cable that is also used
for cable television.• DSL uses twisted-pair wire, similar to that used for
telephones.• Fiber-optic cable uses glass or plastic strands to transmit
data via light signals.• Satellite is a connection option for those who do not
have access to faster broadband technologies. • WiFi allows users to connect to the Internet wire lessly
but is not as fast as a wired connection.• Mobile broadband is a 3G or 4G service delivered by
cell-phone networks.
Securing WirelessChange your
network name (SSID)
Disable SSID broadcast
Change the default password on your
router
Turn on security protocols
Create a passphrase
Implement media access control
Limit your signal range
Apply firmware upgrade
Some networking factsA network with computers acting as both clients and servers is a peer-to-peer
network
Ethernet is the standard
A hub repeats frames down every attached network
cable
A router connects LANs and directs packets to the
correct LAN
Connection-oriented communication requires the client and server to
acknowledge the transmission
Cybercrime and Identity TheftBy Harbakshish Singh
Cybercrime
The computer as a target- attacking the computers of others
The computer as a weapon- using a
computer to commit crime
The computer as an accessory- using
computer as a fancy filing cabinet to store
illegal or stolen information
Examples of Cybercrime
• Identity theft• Credit Card theft• Computer viruses• Illegal access of computer systems• Auction fraud
Example Cybercrime in current news
Six arrested in $45 million global cybercrime scheme
Worldwide ATM heist that stole $45 million from two
Middle East banks
The six arrested Monday were "cashers" in the scheme, withdrawing
approximately $2.8 million from more than 140 ATMs in
New York City
Cybercrime news article
Types of Viruses
Boot sector viruses
Logic bombs
and time bombs
Worms
Scripts and
macro viruses
E-mail viruses
Encryption viruses
What is social engineering, and how do I avoid falling prey to phishing?
Social engineering schemes use human interaction, deception, and trickery to fool people into revealing sensitive information such as credit card numbers and passwords.
Phishing schemes usually involve e-mails that direct the unwary to a website that appears to be legitimate, such as a bank site, but that is specifically designed to capture personal information for committing fraud. To avoid phishing scams, you should never reply directly to any e-mail asking you for personal information and never click on a link in an e-mail to go to a website.
Don't fall for scareware scams that attempt to frighten you by pretending there is something wrong with your computer.
Protect Physical Computer Assets
Computing devices should be kept in clean environments
You should protect all electronic devices from power surges by hooking them up through surge protectors
Mobile devices can be protected from theft by installing software that will (1) set off an alarm if the computer is moved; (2) help recover the computer, if stolen, by reporting the computer's whereabouts when it is connected to the Internet; and/or (3) allow you to lock or wipe the contents of the digital device remotely.
The EndPresentation By Harbakshish Singh