Transcript Kentucky 2010 CTE Summer Program

Kentucky 2010 CTE Summer Program
BASIC COMPUTER “HOME” NETWORKING
– Teaching and Troubleshooting
Elaine Horn, [email protected]
Cisco Academy Main Contact
BASIC COMPUTER “HOME” NETWORKING –
Teaching and Troubleshooting
Session length:
• 90 minutes
Target audience:
• Anyone who wants to learn about
home networking
Session description:
• Our classrooms and homes are no longer complete without an
Internet connection. This session will discuss general networking
concepts that could be taught in any class. It will equip teachers
with skills to troubleshoot simple Internet problems. Terminology
needed to understand buying home networking gear including
wireless gear will be defined and activities for teaching computer
networking will also be shared.
Need for…
Internet Service Provider (ISP)
• Company that provides the connections and
support to access the Internet.
• Can also provide additional services such as
Email and web hosting.
• No one gets on the Internet without a host
computer, and no one gets on the Internet
without going through an ISP.
• Teach your students to be wise consumers!
HOME INTERNET CONNECTIONS
Choices to be made -
First decide on type of network technology used
to make connections to the “Internet Cloud”
HOME INTERNET CONNECTIONS
ISP Choices
http://isp1.us/state/kentucky/
Security, storage and email accounts
24/7 support, email, web space
HOME INTERNET CONNECTIONS
ISP Choices
http://isp1.us/state/kentucky/
Speed = 12Mbps, Speed,
Photo Center, Games
Speed = 7Mbps +,
Security, Email
HOME INTERNET CONNECTIONS
ISP Choices
http://isp1.us/find/
Costs can vary greatly from company to company!
Considerations when choosing an ISP
Considerations when choosing an ISP
Services:
 NEED FOR SPEED
Reliability
Security
Email Accounts
 Storage Space
 Support
Need For Speed
Prices Dependent On Services
SPEED TEST terms!
• Download Speed: The speed at which data is sent
from the testing server to your computer.
• Upload Speed: The speed at which data is sent from
your computer to the testing server.
• Latency: The time it takes for data to be sent from
your computer to the testing server and back (the
"round trip time").
• Jitter: The variability in the delay between your
computer and the testing server.
SPEED TEST!
Dslreports.com Speed Tests
http://reviews.cnet.c
om/internet-speedtest/
SPEED TEST!
• http://video.about.com/compnetworking/CableVersus-DSL.htm
HOME INTERNET CONNECTIONS
Equipment to be purchased
HOME INTERNET CONNECTIONS
Equipment to be purchased
Definitions
• Modems:
– use modems to send and receive
information over telephone or cable
lines
• Network cables (Ethernet):
– connect computers to each other
and to other related hardware, such
as hubs and routers
– for normal connections, straightthrough cables needed
– RJ45 end
Definitions
• Network adapters
– also called network interface cards, or NICs
– connect computers to a network so that they
can communicate
– network adapter can be connected to the
USB port on your computer or installed inside
– support different speeds –
• Ethernet – 10 Mbps
• Fast Ethernet - 100 Mbps
• Gigabit Ethernet peak performance up to
1000 Mbps
– in new computers, NICs are pre-installed by
the manufacturer and show a speed rating
which suggests the general performance of
the unit
RJ45 vs RJ11
Definitions
NETWORK ADAPTERS!
Definitions
• Access Point
– connects wireless clients to a wired network
– sends out wireless signals
– If you want to connect your computers wirelessly and you have a router that
provides wireless capability, you don't need an access point
– must plug an access point into a router or a modem with a built-in router or
buy an ISR
• Hubs/Switches
– connect two or more computers to an Ethernet network.
– a switch costs a little more than a hub, but it speeds up the transfer rate of
information
• Router
– enable computers to communicate and they can pass information between
two networks—such as between your home network and the Internet
– capability to direct network traffic is what gives the router its name
– can be wired or wireless
– typically provide built-in security, such as a firewall
HOME INTERNET CONNECTIONS
Equipment to be purchased -
Integrated Services Router (ISR) - Provide
functionality of a switch, router, wireless access
point in one device
Need for IP
DHCP Server –
hands out IP
address
Services - Applications
Services - Applications
Troubleshooting
• Check the physical layer
Troubleshooting
• Check the physical layer
Video – Home Connections - Wireless
• http://video.about.com/compnetworking/Wir
eless-Network-Setup.htm
Wireless Standards
802.11a – 5 GHz RF Spectrum
•transfers data at a maximum rate of 54 megabits per second (Mbps). Downloading a
10 megabyte (MB) photo from the Internet under optimal conditions takes about 1.5
seconds.
802.11b – 2.4 GHz Spectrum
•transfers data at a maximum rate of 11 Mbps. Downloading a 10 megabyte (MB)
photo from the Internet under optimal conditions takes about 7 seconds.
802.11g – 2.4 GHz Spectrum
•transfers data at a maximum rate of 54 Mbps. Downloading a 10 megabyte (MB)
photo from the Internet under optimal conditions takes about 1.5 seconds.
802.11n – NEWEST - 2.4 GHz (backwards compatible with g and b)
•depending upon the number of data streams the hardware supports, 802.11n can
theoretically transmit data at up to 150 Mbps, 300 Mbps, 450 Mbps, or 600 Mbps.
Wireless Caution
Note
The transfer times listed are under ideal conditions. They aren't necessarily
achievable under normal circumstances because of differences in hardware, web
servers, network traffic conditions, and so on.
•Wireless is often slower than a wired connection.
•Wireless can be affected by interference from things such as walls, large metal
objects, and pipes. Also, many cordless phones and microwave ovens can interfere
with wireless networks when they're in use.
•Wireless networks are typically about half as fast as their rated speed under all but
ideal conditions.
Wireless Standards
Wireless Security
Wireless Security
• Service Set Identifier (SSID) –
– used to tell wireless devices which WLAN they
belong to and with which other devices they
communicate
– case-sensitive
– do not use defaults
– do not broadcast
• The program can come in handy if you are using a WLAN and you
don't have signal or it is not working properly.
• NetStumbler is a tool for Windows that allows you to detect Wireless
Local Area Networks (WLANs) using 802.11b, 802.11a, 802.11g and
802.11n.
• Here are some key features of "NetStumbler”:
• Verify that your network is set up the way you intended.
• Find locations with poor coverage in your WLAN.
• Detect other networks that might be causing interference with
your network.
• Detect unauthorized "rogue" access points in your workplace.
• Help aim directional antennas for long-haul WLAN links.
• Use it recreationally for WarDriving.
USE Wi-Fi Protected Access (WPA) encryption!
Since there are no distinct boundaries on a wireless network, and all traffic is transmitted
through the air, it is easy for an attacker to intercept, or sniff the wireless frames. Encryption is
the process of transforming data so that even if it is intercepted it is unusable.
SAY NO TO - Wired Equivalency Protocol (WEP) encryption
Secure the ACCESS POINT
TROUBLESHOOTING!
• Sample Diagrams of Home Networks
Effective network security comes from a combination of
products and services. SECURE YOUR PC!
Effective network security comes from a combination of
products and services. SECURE YOUR PC!
• Keep PC Firewall ON!
• Run an AntiVirus software!
• Run Spyware/Malware software!
• Malware, short for malicious software, is software designed to infiltrate a
computer system without the owner's informed consent. The term "computer
virus" is sometimes used as a catch-all phrase to include all types of malware,
including true viruses.
• Software is considered to be malware based on the perceived intent of the
creator rather than any particular features. Malware includes computer viruses,
worms, trojan horses, spyware, dishonest adware, crimeware, most rootkits, and
other malicious and unwanted software.
• Spyware, software that secretly gathers information about a person or
organization. Any malicious software that is designed to take partial or full control
of a computer's operation without the knowledge of its user.
TROUBLESHOOTING!
TROUBLESHOOTING!
• A number of software utility programs are available that
can help identify network problems. Most of these utilities
are provided by the operating system as command line
interface (CLI) commands. The syntax for the commands
may vary between operating systems.
• Some of the available utilities include:
–
–
–
–
–
ipconfig - Displays IP configuration information
ping - Tests connections to other IP hosts
tracert - Displays route taken to destination
netstat - Displays network connections
nslookup - Directly queries the name server for information on a
destination domain
TROUBLESHOOTING!
• ipconfig - Displays IP configuration information
• IP addresses of 169.254.x.y means that your
computer could not reach your DHCP servers
to be assigned an address
• IP address of 127.x.x.x is a loopback address
TROUBLESHOOTING!
Sample Diagrams
Need an ISP (Internet Service Provider)
THE CLOUD!
Kentucky 2010 CTE Summer Program
BASIC COMPUTER “HOME” NETWORKING
– Teaching and Troubleshooting
Elaine Horn, [email protected]
Cisco Academy Main Contact