Transcript Unit 10- Network Fundamentals

NETWORK
FUNDAMENTALS
Unit 10
Objectives
■ Define communication networks and identify the differences
between public and private networks
■ Describe common hardware and software components in a
computer network
■ Identify network types
■ Identify the benefits of a network
■ Evaluate the risks of network computing
■ Identify and resolve common networking connection
problems
Network
■ 2 or more connected
devices
■ Can transfer data
Public vs. Private Networks
■ PSTN- Public Switched Telephone Network
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Voice-based telephone network
Established one to one connection (circuit-switched)
Includes mobile & landline today
Aka POTS (Plain Old Telephone Network)
■ VPN- Virtual Private Network
– Remote user uses public network (Internet) to access a private
network (home office or work)
– All data is encrypted
– Work at home, travelling employee, remote offices use this
Network Types- LAN
■ Local Area Network
– In a small area
– Office, school, house
■ WLAN
– Wireless
– Need Wi-Fi card
Network Types- WAN
■ Wide Area Network
■ Large geographic area
– Two or more LANs connected by routers
– Big businesses with office around country or world
– Internet is biggest WAN
■ Connected by fiber, satellites, telephone
Network Types- Client-Server
■ Server manages &
provides a service
to client
■ Network OS on
server
– Maintain all
clients centrally
■ Username &
password
Network Types- Peer to Peer
■ No server
– All PCs equal
– Each PC maintained
on its own
■ Small office or house
■ Easy to set up
Network Types- Internet
■ Global network of connected, smaller networks
■ You connect to it through an ISP
■ World Wide Web & email are most popular uses
Network Types- Intranet
■ Web based for internal company use
– Handbooks, manuals, employment forms, work news, etc
– Only can access from within that company
– Through web browser
Network Types- Extranet
■ Similar to Intranet
■ Outside users with user name & password can have
access to internal info
Project
■ Identify the type of network handout
■ Teknimedia:
– C1.1-5
– C1.43-44
– C1.49
IDENTIFYING NETWORK
COMPONENTS
Hardware & Software Components
Modem
■ Modulate-Demodulate

Digital to analog/analog to digital
■ Allows data to be transmitted over a line and changed
from one signal to another
■ Dial-up, DSL, Cable Modems
Dial-up Modem
■ Dial-Up Modem
– Internal or External
– Data over phone lines
■ Dialed into a phone number
– SLOWWWWW
■ Old- 300 bits per second (bps) or
baud rate
■ Now- 56k or kilobits per second
Broadband Cable Modem
■ Data over Coaxial (Coax) cable
■ High speed, always on
– Broadband
– 20Mbps (Megabits per second) & up
Cable Modem Hookup
DSL Modem
■ Digital Subscriber Line
■ High speed, always on
– Broadband
– Through phone lines
– 1.5-3Mbps
■ Can use phone & Internet at
same time
– Filters on phones
DSL Modem Hookup
Other Communication Devices
■ Media
– Coaxial cable, twisted-pair (Ethernet), fiber optic, wireless
– Connects to NIC
■ T-1 Line
– Dedicated fiber line to your business
– Voice & data
– 1.5Mbps is all for you!
■ Hub (OLD)
– Connects PCs together
– Dumb device
Switch, Router, Multipurpose Device
■ Switch
– Better & faster than a hub
– Built into back of these routers
■ Router/Multipurpose Device
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Connects computers
Shares one Internet connection
May allows wireless access
Firewall
■ Wireless Adapters or NIC
How They Connect
Addressing
■ Network devices need an IP Address & MAC Address to
communicate (TCP/IP)
– IP: 192.168.1.120 (assigned logically)
– MAC: 0A-B5-74-C3-1E-FF (physically on NIC)
■ DNS
– Translates names to IP addresses
Communicating
■ Protocols
– Set of rules for communication
– TCP/IP
■ Packet Switching
– Data is split into smaller segments/packets in NIC
– Reassembled by destination NIC
Review- 4Q
■ Which Internet connection sends high speed broadband over
analog phone lines?
– DSL
■ If a coax cable connects to your modem, which Internet service do
you have?
– Cable modem or FiOS
■ Every computer needs an ___ & ____ to communicate on a
network.
– IP address & MAC address
■ The 4 LAN ports on the back of a home router is really what device?
– Switch
Networks Benefits vs. Risks
Benefits
Risks
Why Hack?
■ Theft of services
■ Theft of Information
■ Hatred & vengeance
■ For the thrill of it
Review- 5Q
■ T or F. Hackers invade other people’s computers only for fun.
■ T or F. Software sharing is one of the benefits of networking.
■ When you are on a network, you should assume that your
email is not _____________?
– Private
■ T or F. It is easier for a virus to spread on a network.
Review- 4Q
■ How is the network at school different than your home one?
– How is it the same?
■ Which type of network has an OS & requires a username/password for
access?
– Client-server
■ What are two popular Internet features?
– Email & Web
■ At Starbucks, you can access the Internet with your laptop & no wires.
What type of network is this?
– WLAN
Review- 5Q
■ T or F. A modem converts analog to digital signals.
– True
■ T or F. Hackers invade other people’s computers only for fun.
– False
■ A _______ is confined to a limited geographical area.
– LAN
■ A _______ is made up of several local area networks.
– WAN
■ A _______ is a simple device that connects multiple
computers together.
– Hub
NETWORK
FUNDAMENTALS
Unit 10