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Networking Fundamentals - Part 2. CS 1 Rick Graziani Cabrillo College. ISP Internet Service Provider. IP Address =. 24.205.224.36. Sub Mask =. Default Gateway =. Default Gateway 75.140.156.1. DNS Server =. ISP Internet Service Provider. DHCP. IP Address =. 24.205.224.36.

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networking fundamentals part 2

Networking Fundamentals - Part 2

CS 1

Rick Graziani

Cabrillo College

slide2

ISP

Internet

Service

Provider

IP Address =

24.205.224.36

Sub Mask =

Default Gateway =

Default Gateway

75.140.156.1

DNS Server =

Rick Graziani graziani@cabrillo.edu

slide3

ISP

Internet

Service

Provider

DHCP

IP Address =

24.205.224.36

75.140.157.97(Public)

Sub Mask =

255.255.255.252

Default Gateway =

75.140.156.1

Default Gateway

75.140.156.1

DNS Server =

24.205.224.36

Rick Graziani graziani@cabrillo.edu

slide4

DSL/Cable Modem

Router

Rick Graziani graziani@cabrillo.edu

slide8

ISP

Internet

Service

Provider

IP Address =

Sub Mask =

Default Gateway =

24.205.224.36

DNS Server =

IP Address =

Default Gateway

75.140.156.1

Sub Mask =

Default Gateway =

DNS Server =

Public IP Address

75.140.157.97

Router/Default Gateway

IP Address =

Default Gateway: 192.168.1.1

DHCP Server:

Network = 192.168.1.0 (Private)

Sub Mask = 255.255.255.0

First host: 192.168.1.100

Sub Mask =

Default Gateway =

DNS Server =

Network Address Translation

75.140.157.97  192.168.1.host

Rick Graziani graziani@cabrillo.edu

slide9

ISP

Internet

Service

Provider

IP Address =

192.168.1.100

Sub Mask =

255.255.255.0

Default Gateway =

192.168.1.1

24.205.224.36

DNS Server =

24.205.224.36

IP Address =

192.168.1.101

Default Gateway

75.140.156.1

DHCP

Sub Mask =

255.255.255.0

Default Gateway =

192.168.1.1

DNS Server =

Public IP Address

75.140.157.97

24.205.224.36

Router/Default Gateway

IP Address =

192.168.1.102

Default Gateway: 192.168.1.1

DHCP Server:

Network = 192.168.1.0

Sub Mask = 255.255.255.0

First host: 192.168.1.100

Sub Mask =

255.255.255.0

Default Gateway =

192.168.1.1

DNS Server =

Network Address Translation

75.140.157.97  192.168.1.host

24.205.224.36

Rick Graziani graziani@cabrillo.edu

slide12

IP Address =

192.168.1.100

I need an IP address www.bayfed.com

Sub Mask =

255.255.255.0

Default Gateway =

192.168.1.1

24.205.224.36

DNS Server =

www.bayfed.com is at 65.64.172.199

24.205.224.36

ISP

Internet

Service

Provider

Default Gateway

75.140.156.1

Public IP Address

75.140.157.97

Bay Federal

65.74.172.199

Router/Default Gateway

Rick Graziani graziani@cabrillo.edu

slide13

IP Address =

192.168.1.100

Sub Mask =

255.255.255.0

Default Gateway =

192.168.1.1

24.205.224.36

DNS Server =

85.255.112.1

ISP

Internet

Service

Provider

Default Gateway

75.140.156.1

I need an IP address www.bayfed.com

Public IP Address

75.140.157.97

Bay Federal

65.74.172.199

Router/Default Gateway

www.bayfed.com is at 85.255.112.99

85.255.112.1

85.255.112.99

Rick Graziani graziani@cabrillo.edu

1981 primitive internet report on kron
1981 primitive Internet report on KRON

http://www.youtube.com/watch?v=5WCTn4FljUQ&feature=player_embedded

Rick Graziani graziani@cabrillo.edu

circuit switched
Circuit Switched
  • Circuit Switching:A form of data communication which establishes a single connection or circuit between source and destination to carry the data stream.
  • Like a conventional telephone system.
  • When a subscriber makes a telephone call the dialed number is used to set switches in the exchanges along the route of the call so that there is a continuous circuit from the originating caller to that of the called party.

Rick Graziani graziani@cabrillo.edu

packet switching
Packet Switching
  • Packet Switching: A form of data communications which breaks a data stream into small sections, sends them separately by the best available channels and reassembles the original data stream at its destination.
  • An alternative is to allocate the capacity to the traffic only when it is needed, and share the available capacity between many users.

Rick Graziani graziani@cabrillo.edu

wireless access point
Wireless Access Point
  • A wireless access point is a device that connects wireless devices (laptops, etc.) to a wired network, usually an Ethernet LAN.

Rick Graziani graziani@cabrillo.edu

wireless access point1
Wireless Access Point
  • In our example the wireless access point (AP) will include a Router.

Rick Graziani graziani@cabrillo.edu

putting it together
Putting it together
  • Exactly the same as connecting a router without an AP.

Rick Graziani graziani@cabrillo.edu

configuring the ap and router
Configuring the AP and Router

Wireless Settings:

  • SSID (Service Set Identifier) – Name of your network
  • Security: WPA2, WPA, WEP, or none

SSID

Rick Graziani graziani@cabrillo.edu

slide22

Configuring the AP and Router

Wireless Settings:

  • Security: WPA2, WPA, WEP, or none

WPA2

Rick Graziani graziani@cabrillo.edu

slide23
SSID
  • The SSID is what will be displayed when people with wireless computers are looking for a wireless LAN.

Rick Graziani graziani@cabrillo.edu

linksys wrt54g
Linksys WRT54G

Router Information

  • IP Address from ISP
  • Connects to your DSL/Cable Modem
  • NAT (Network Address Translation)

Local Network

  • Ethernet Switch
  • Connect “wired” computers
  • DHCP Server (optional)

Wireless

  • SSID: MyHomeNetwork
  • DHCP Server: (optional)
  • Channel: 11
  • Encryption Function: WPA

Rick Graziani graziani@cabrillo.edu

you choose
You choose…
  • There are many resources to discuss the possible health risks or wireless LANs.
  • As a networking and WLAN user and instructor I have my own thoughts which I will share.
  • If you are concerned, then research the information and come to your own conclusions.
  • The following information is from my own research and experience.

Rick Graziani graziani@cabrillo.edu

wireless frequency
Wireless Frequency
  • Wireless APs operate at:
    • 2.4 GHz
    • 5 GHz
  • 2 GHZ! That’s the same as my microwave oven, isn’t that dangerous?
  • Answer: No.
    • Electromagnetic waves happen naturally.
      • Light is an electromagnetic wave
    • It is not the frequency, but the wattage, the power.
      • Any electromagnetic wave can be dangerous with too much power.
      • A 25 watt light bulb is safe, but it wouldn’t be safe at 250,000 watts
    • Wireless access points generate signals at 1/10th of a watt.
      • Like all electromagnetic waves, the signal does not fade in a linear manner, but inversely as the square of the distance.

Rick Graziani graziani@cabrillo.edu

slide27

www.britishlibrary.net

Rick Graziani graziani@cabrillo.edu

inverse square law
Inverse square law

10

20

30

40

50

100

  • Double the distance of the wireless link, we receive only ¼ of the original power.
  • Triple the distance of the wireless link, we receive only 1/9 the original power.
  • Move 5 times the distance, signal decreases by 1/25.

Point A

10 times the distance 1/100 the power of A

3 times the distance 1/9 the power of Point A

2 times the distance ¼ the power of Point A

5 times the distance 1/25 the power of Point A

Rick Graziani graziani@cabrillo.edu

putting it in some perspective
Putting it in some perspective
  • Measurements from an antenna transmitting 100mW at 1 inch
  • Remember a milliwatt is 1/1,000th of a Watt
  • Microwave oven typically operates at 1,000 watts in a confined space.

1” 100 mW 1/10th watt

2” 25 mW 1/40th watt

4” 6.25 mW 1/166th watt

8” 1.56 mW 1/1000th watt

16” 0.39 mW 4/10,000th watt

32” 0.097 mW 1/10,000th watt

64” (5.3 ft) 0.024 mW 2/100,000th watt

128” (10.6 ft) 0.006 mW 6/1,000,000th watt

256” (21.3 ft) 0.0015 mW 15/10,000,000th watt

  • Light bulbs would also be dangerous the were 10,000 to 1,000,000,000,000 stronger.
  • A 250,000 watt up to a 250,000,000,000,000 watt light bulb would also be dangerous.

Rick Graziani graziani@cabrillo.edu

wireless n
Wireless N
  • Wireless N provides better speeds (bandwidth) and better range by utilizing multiple antennas.
  • Backwards compatible with 802.11 b and g.

Rick Graziani graziani@cabrillo.edu

wireless security everyone can hear
Wireless Security – Everyone can hear
  • Others can “hear” or capture your information.
  • Wireless signals are propagated, sent, similar to our voice sound waves.

Rick Graziani graziani@cabrillo.edu

wireless security everyone can hear1
Wireless Security – Everyone can hear
  • If we don’t want them to understand what they hear, we can encrypt or code the information.
  • As long a our wireless computer and access point are using the same encryption algorithm, such as WEP or WPA.

Rick Graziani graziani@cabrillo.edu

wireless security
Wireless Security
  • Without any security, anyone can:
    • Use your wireless access point to access your network and the Internet.
    • Capture your information from your wireless computer.

Rick Graziani graziani@cabrillo.edu

wireless security1
Wireless Security

CommView

DriftNet

Rick Graziani graziani@cabrillo.edu

wireless security2
Wireless Security
  • Your web browsing or email access should already be secured.
  • Look for the lock

Rick Graziani graziani@cabrillo.edu

wireless security3
Wireless Security
  • Why you should protect your wireless network with WPA
    • http://www.youtube.com/watch?v=A88XB7_Jz7s
  • Wireless Hacking
    • http://www.youtube.com/watch?v=qP1BOZqrp5g&feature=related

Rick Graziani graziani@cabrillo.edu

mac cloning
MAC Cloning

Rick Graziani graziani@cabrillo.edu

cell phones do not cause explosions
Cell Phones do not cause explosions
  • http://www.youtube.com/watch?v=OQ0aTMMITp8
  • http://www.youtube.com/watch?v=NRGrFLRs9xE&feature=related

Rick Graziani graziani@cabrillo.edu

careers in information technology
Careers in Information Technology

Rick Graziani graziani@cabrillo.edu

computer support specialist
Computer Support Specialist
  • Installing computer hardware and software.
  • Troubleshooting
  • Maintenance and upgrades

Rick Graziani graziani@cabrillo.edu

networking system administrator
Networking: System Administrator
  • Installing, configuring, and maintaining network servers
  • UNIX, LINUX, Microsoft
  • Web, DNS, DHCP, Mail Servers
  • Backup and recovery, user administration
  • Security

Rick Graziani graziani@cabrillo.edu

networking network technician analyst
Networking: Network Technician/Analyst
  • Install, manage, troubleshoot network infrastructure:
    • Routers, Switches, Cables, Wireless Access Points
  • Issues: Security, Quality of Service, Video On Demand, Voice over IP

Rick Graziani graziani@cabrillo.edu

keeping up on technology
Keeping up on technology
  • Wireless
  • Security

Rick Graziani graziani@cabrillo.edu

safe surfing
Safe Surfing
  • Adware
    • Pop-ups
    • Spyware
    • Blocking Pop-ups
  • Java Traps or Pop-Up Hell
  • Spyware
    • Blocking Spyware
  • Cookies
  • Virus Protection
  • Spam
    • Blocking Spam

Rick Graziani graziani@cabrillo.edu

adware
Adware
  • Adware or advertising-supported software is any software application in which advertisements are displayed while the program is running.
  • Adware helps recover programming development costs, and helps to hold down the price of the application for the user (even making it free of charge)—and, of course, it can give programmers a profit, which helps to motivate them to write, maintain, and upgrade valuable software.

Rick Graziani graziani@cabrillo.edu

what are pop ups wikipedia org
What are Pop-ups? (Wikipedia.org)
  • Pop-up ads are a form of online advertising on the Web where certain websites open a new web browser window to display advertisements.
  • Usually generated by JavaScript
  • A less intrusive variation on the pop-up window is the pop-under advertisement.
    • This opens a new browser window, but in the background, so as not to interrupt the user's page-view.

Rick Graziani graziani@cabrillo.edu

slide50

From Gain Publishing: www.gainpublishing.com/ about/

Rick Graziani graziani@cabrillo.edu

slide51
For early advertising-supported websites, banner ads were sufficient revenue generators.
  • But in the wake of the dot com crash, prices paid for banner advertising clickthroughs decreased and many vendors began to investigate more effective advertising methods.
  • Pop-up ads by their nature are difficult to ignore or overlook, and are claimed to be more effective than static banner ads.
  • Pop-ups have a much higher click rate than web banner ads do.
    • What are Pop-ups? (Wikipedia.org)

Rick Graziani graziani@cabrillo.edu

what are pop ups wikipedia org1
What are Pop-ups? (Wikipedia.org)
  • Most users regard pop-ups as a nuisance.
  • In the early 2000s, all major web browsers except Internet Explorer allowed the user to block pop-ups almost completely.
  • In 2004, Microsoft released Windows XP SP2, which added pop-up blocking to Internet Explorer.
  • Many of the latest pop-ups are created using Flash and have extensive animation and trickery.

Ultimate irony!

Rick Graziani graziani@cabrillo.edu

pop up looks real
Pop-up, looks real…

http://www.news3insider.com/finance/google-hiring-you.html

Rick Graziani graziani@cabrillo.edu

block pop up windows with internet explorer
Block Pop-up Windows with Internet Explorer

Rick Graziani graziani@cabrillo.edu

c net pop ups mean more
C/NET – Pop-ups mean more $$$
  • Publishers willingly allow pop-ups or pop-unders because they command higher prices, and they're in high demand by advertisers.

Rick Graziani graziani@cabrillo.edu

java trap or pop up hell
“Java Trap” or “Pop-up Hell”
  • Pornographic websites are among the most common users of pop-up ads.
  • Some particularly vicious types of pop-up ads have been specifically designed to "hijack" a user's Internet session.
  • As each window is closed by the user it activates another window -- sometimes indefinitely.
  • Usually the only way to stop this is to close the browser.
  • Mouse Trapping: Another variation of pop-up fills an entire screen with an ad or Web page, removing any menu bars or other on-screen icons by which the user can close the window.

Rick Graziani graziani@cabrillo.edu

spyware wikipedia org
Spyware (Wikipedia.org)
  • Spyware is computer software that gathers and reports information about a computer user without the user's knowledge or consent.
  • May perform many different functions, including:
    • Delivery of unrequested advertising (pop-up ads in particular),
    • Harvesting private information
    • Re-routing page requests to illegally claim commercial site referral fees
  • Spyware or Malware Can include:
    • keystroke loggers
    • denial-of-service (DoS) attack agents

Rick Graziani graziani@cabrillo.edu

fighting spyware
Fighting Spyware
  • Spybot (www.safer-networking.org)
  • PestPatrol (www.pestpatrol.com)

Rick Graziani graziani@cabrillo.edu

cookies
Cookies
  • A cookie is information sent by a server to a browser and then sent back to the server each time it accesses that server.
  • Amongst other uses, cookies enable websites to be customized for individual users once browsing patterns have been established.
  • Cookies only store information that you provide.

Rick Graziani graziani@cabrillo.edu

first time you login
First time you login

HTTP Requests: GET (first time)

HTTP: Response Set-cookie: ID 5551212

HTTP Server

HTTP Requests (GET) now include ID - 5551212

HTTP Client

Web server can now track clients activities on the web site.

Rick Graziani graziani@cabrillo.edu

each time you login
Each time you login…

HTTP: Cookie 5551212 included

HTTP Server

HTTP data customized for Rick Graziani

HTTP Client

Rick Graziani graziani@cabrillo.edu

cookies purpose
Cookies - Purpose
  • Typically this is used to authenticate or identify a registered user of a web site as part of their first login process or initial site registration without requiring them to sign in again every time they access that site.
  • Other uses are maintaining a "shopping basket" of goods selected for purchase during a session at a site, site personalization (presenting different pages to different users), and tracking a particular user's access to a site.

Rick Graziani graziani@cabrillo.edu

cookies permissions
Cookies - Permissions
  • A browser may or may not allow the use of cookies.
  • The user can usually choose a setting.
  • Microsoft Internet Explorer
    • Tools > Internet Options > Privacy Tab
    • Use slider to set options, or use advanced options

Rick Graziani graziani@cabrillo.edu

virus protection
Virus Protection
  • In computer security technology, a virus is a self-replicating program that spreads by inserting copies of itself into other executable code or documents

Rick Graziani graziani@cabrillo.edu

http techguylabs com
http://techguylabs.com/

Rick Graziani graziani@cabrillo.edu

be careful when opening attachments
Be careful when opening attachments!

Rick Graziani graziani@cabrillo.edu

slide68

“According to folks working on the case who talked to us at the HTCIA HighTech Crime Investigation Association international training this fall, the major method used by the Chinese hackers was to identify Google workers through their Facebook pages, trace back through their home town / highschool information, get the yearbook, make fake email / facebook accounts in the names of others from the yearbook, and make friends with the Google workers on the net. Eventually they sent them malware in photos which gave the Chinese the entry into the Google work systems.”

Rick Graziani graziani@cabrillo.edu

computer virus spyware
Computer Virus, Spyware
  • Computer Virus, Spyware
  • http://www.youtube.com/watch?v=uK5ija2gVbY
  • How Computer Viruses Work
  • http://www.youtube.com/watch?v=sxal31zIKdE&feature=related

Rick Graziani graziani@cabrillo.edu

slide70

May 4th, 2009

Rick Graziani graziani@cabrillo.edu

spam wikipedia
Spam (Wikipedia)
  • Spamming is the act of sending unsolicited electronic messages in bulk.

Rick Graziani graziani@cabrillo.edu

anti spam
Anti-Spam
  • Spammers obtain e-mail addresses by a number of means:
    • Web pages
    • guessing common names at known domains
    • "e-pending"
    • searching for e-mail addresses corresponding to specific persons
  • Many e-mail spammers go to great lengths to conceal the origin of their messages.
  • Spoofing e-mail addresses - spammer modifies the e-mail message so it looks like it is coming from another e-mail address.
  • Among the tricks used by spammers to try to circumvent the filters is to intentionally misspell common spam filter trigger words, ie. "viagra" might become "vaigra", or by inserting other symbols within the word, i.e. "v/i/a/g./r/a".

Rick Graziani graziani@cabrillo.edu

the nigerian email spam scam
The Nigerian Email Spam Scam
  • Email SPAM Scam
  • The Nigerian Email Spam Scam
  • http://www.youtube.com/watch?v=kYNi2gVpuig
  • ABC Report on Nigerian Scammers
  • http://www.youtube.com/watch?v=8PQANsFisvU&feature=related
  • http://www.youtube.com/watch?v=7PVK0R01tRw&feature=related
  • http://www.youtube.com/watch?v=puYEUs18MFI&feature=related

Rick Graziani graziani@cabrillo.edu

passwords
Passwords
  • Combine letters, numbers, and symbols.
  • Use words and phrases that are easy for you to remember, but difficult for others to guess.
  • Avoid sequences or repeated characters. "12345678," "222222," "abcdefg,"
  • Avoid using only look-alike substitutions of numbers or symbols.
    • 'i' with a '1'
    • 'a' with '@‘
    • ‘o’ with a 0’
    • as in "M1cr0$0ft" or "P@ssw0rd"
  • At least 8 characters; more than14 characters is even better
  • But these substitutions can be effective when combined with other measures:
    • 1$erf@h00k

Rick Graziani graziani@cabrillo.edu

hoaxes scams and fraud
Hoaxes, Scams, and Fraud
  • This hoax generated thousands of emails with the first day alone.

Rick Graziani graziani@cabrillo.edu

google name or go to snopes com
Google name or go to Snopes.com

Rick Graziani graziani@cabrillo.edu

virus hoax
Virus Hoax
  • While it is true that PowerPoint files are capable of containing computer viruses, there is no evidence that an infected file called "Life Is Beautiful" even exists, let alone is circulating on the Internet.

Rick Graziani graziani@cabrillo.edu

swiffer wetjet
Swiffer Wetjet

Rick Graziani graziani@cabrillo.edu

typical email scam
Typical Email Scam

Subject:    Account Confirmation {Account Expires in 4 days}

Date:       Mon, 15 Sep 2008 06:14:39 -0400

From:       Leboyd, Nichole <nleboyd@msm.edu>

Dear Staff/Student

This message is from the IT Service messaging center to all subscribers/webmail users. We are currently upgrading the webmail data base and e-mail centers due to an unusual activities identified in our email system. We are deleting all unused Webmail Accounts. You are required to verify and update your Webmail by confirming your Webmail identity. This will prevent your Webmail account from been closed during this exercise. In order to confirm your Webmail identity, you are to provide the following data;

Confirm Your WebMail Identity Below;

First Name:

Last Name:

Username/ID:

Password:

Date of Birth:

Warning: Any subscriber/webmail user that refuses to verify and subsequently update his/her Webmail within 4 days of receiving this warning will lose his/her Webmail Account permanently.

We thank you for your prompt attention to this matter. Please understand that this is a security measure intended to help protect your Webmail Account. We apologise for any inconvenience.

Regards,

Leboyd Nichole

Webmail Administrator.

Rick Graziani graziani@cabrillo.edu

wells fargo scam
Wells Fargo (Scam)

Rick Graziani graziani@cabrillo.edu

fake site
Fake Site

Rick Graziani graziani@cabrillo.edu

fake and real sites
Fake and Real Sites

Rick Graziani graziani@cabrillo.edu

wells fargo reporting fraud emails
Wells Fargo – Reporting Fraud Emails

Rick Graziani graziani@cabrillo.edu

paypal
PayPal

Rick Graziani graziani@cabrillo.edu

slide85
USAA

Rick Graziani graziani@cabrillo.edu

changing who from
Changing Who From

Rick Graziani graziani@cabrillo.edu

create fake email
Create Fake Email

Rick Graziani graziani@cabrillo.edu

creating fake link
Creating Fake Link

Rick Graziani graziani@cabrillo.edu

receiver
Receiver

Rick Graziani graziani@cabrillo.edu

looking at options doesn t help
Looking at Options doesn’t help

Rick Graziani graziani@cabrillo.edu

slide91

Click on Link…

Rick Graziani graziani@cabrillo.edu

rickroll d
RickRoll’D

Rick Graziani graziani@cabrillo.edu

killer whale lands on kayak
Killer Whale Lands On Kayak (?)
  • http://www.youtube.com/watch?v=H2KBpauoDNs
  • http://www.youtube.com/watch?v=NjwxAJYKFbE

Rick Graziani graziani@cabrillo.edu

sites to check for hoaxes
Sites to check for hoaxes
  • http://urbanlegends.about.com/od/internet/a/current_netlore.htm
  • http://www.snopes.com/
  • http://www.hoax-slayer.com/

Rick Graziani graziani@cabrillo.edu

internet safe surfing1

Internet: Safe Surfing

CS 1

Rick Graziani