network & internet security
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Network & Internet Security. Chapter 4. Information Technology. Helps to produce, manipulate, store, communicate, and/or disseminate information Consists of Computers + Communications Most computers today have Internet access. LANS, MANS, and WANS. - PowerPoint PPT PresentationTRANSCRIPT
Network & Internet Security
Chapter 4
Information Technology
• Helps to produce, manipulate, store, communicate, and/or disseminate information
• Consists of Computers + Communications• Most computers today have Internet access
LANS, MANS, and WANS
• Local area network (LAN) - a network of computers and other devices that is confined to a relatively small space, such as one building or even one office.
• Metropolitan area network (MAN) - a network that connects clients and servers in multiple buildings in a region.
• Wide area network (WAN) - a network that connects two or more geographically distinct LANs
LAN (Short distance)
MAN (Usually within a city)
WAN (Large distance)
Seattle
San Diego
Chicago
Dallas
Washington
Boston
From the Analog to the Digital Age
• Tape recorders, voices, and musical instruments are analog.
• CDs are digital.
Going Digital
• Music CD’s• Computers• TVs• Web TV• Telephones• Movies (DVD)• Newspapers
Digital Television
• Clearer picture
• Supports HDTV
HDTV
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Forms of Connectivity
• Videoconferencing• Virtual Private Networks• Telecommuting & virtual offices• Home networks (WiFi)• Cell Phones• Bluetooth
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Videoconferencing
VPNs
• Virtual Private Networks– Private networks that use a public network, usually the
internet, to connect remote sites
VPN (Virtual Private Network)
Node
node
node
Nodenode
node
Node
Internet
Network Concerns and Protection
• Hackers
• Viruses
• Snooping
• Firewalls
Cyberthreats, Hackers, & Safeguards
• Problem: • Initially no security was built into the Internet.• The internet is used by some people who are
not trustworthy.• All it takes is one computer on a LAN that has
been compromised for all computers on it to be vulnerable.
Cybercrime
• Crimes committed with or against computers and networks
• Includes unauthorized access or use• Hacking
– Individual information– Business information– National security information
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Cyberthreats, Hackers, & Safeguards
• Hackers– People who gain unauthorized access to computers or
networks, often for fun or to see if they can (not good)
• Crackers– Malicious hackers who break into computers for malicious
purposes
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Threats to Computers & Communications Systems
• WormsA program that copies itself
repeatedly into a computer’s memory or onto a disk drive
• VirusesA is a “deviant” program, stored
on a computer hard drive, that can cause unexpected and undesirable effects.
Viruses & Worms
• How they spread– Via e-mail attachments– By infected floppies or CDs– By clicking on infiltrated websites– By downloading from infected files from
websites– Through infiltrated Wi-Fi hotspots– From one infected PC on a LAN to
another• What can you do about it?
– Install anti-virus software and subscribe to the automatic anti-virus update service
Cyberthreats, Hackers, & Safeguards
• Trojan Horses – Programs that pretend to be a useful program
such as a free game or screensaver.– Carry viruses or malicious instructions that
damage your computer or install a backdoor or spyware
– Backdoors and spyware allow others to access your computer without your knowledge
Backdoor
• Sometimes installed by a virus• http://www.youtube.com/watch?v=ahcVp8vIicI
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Disgruntled Employees
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Computer Criminals
• Hackers• Crackers• Employees
Protecting Your Computer
• Safeguards– Use antivirus software, and keep it current– Install a firewall to filter out undesirable traffic– Use robust passwords –
• Minimum 8 characters with letters, numbers, characters• 4cats is not a good password, but f0UrK@tTz is
– Install antispyware software– Encrypt financial and personal records – Back up your data, so if your PC is attacked and
must be reformatted, you can restore your data
Protecting Your Computer
• Encryption– The process of altering readable data into
unreadable form to prevent unauthorized access– Two forms:
• Private Key encryption means the same secret key is used by both the sender and receiver to encrypt and decrypt a message
• Public Key encryption means that two keys are used
Encryption
• Scrambles data before transmission• Uses encryption key• Plaintext versus cipher text
Proof of Authenticity
• Certificate Authority• Entity that issues digital certificates• Digital Certificate
– Provided by a Certificate Authority– Has an expiration date
• Digital Signature– Gives a recipient reason to believe that the
message was created by a known sender
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Validation
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Vulnerable Communication
• Home WiFi Networks• Cellular phones• Bluetooth
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Cellular Phones
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Wireless Communications MediaShort-range Wireless
• Wi-Fi (802.11) networks– Wi-Fi b, a, and g correspond to 802.11b, 802.11a, and 802.11g– 802.11 is an IEEE wireless technical specification– 802.11b is older, transmits 11 megabits per second – 802.11a is faster than b but with weaker security than g– 802.11g is 54 megabits per second and transmits 50 ft
• Warning! Security is disabled by default on Wi-Fi
Wireless Communications MediaPersonal Area Wireless
• Bluetooth– Short-range wireless standard to link cellphones, PDAs,
computers, and peripherals at distances up to 30 ft– Named after King Harald Bluetooth, the Viking who unified
Denmark and Norway– Transmits 720 kilobits per second
– Bluetooth can also be used to eavesdrop on networks– Turn it off on your cell phone unless you need it at that time
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SafeguardsIdentification & Access
• What you have– Cards, keys, signatures, badges, RFID,
USB key
• What you know– PINs, passwords, personal information
• Who you are– Physical traits
• Biometrics – fingerprints, iris, face recognition
Joe Smith
Stealing Passwords
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http://www.youtube.com/watch?v=O68zx6xTubs
http://boingboing.net/2011/03/07/nevada-student-charg.html
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Iris Scan
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Safeguards
• Encryption• Protection of software & data
– Access, audit, & people controls• Disaster-recovery plans
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Protection of Software & Data
• Security procedures– Control of access– Audit controls– People controls
• Disaster-recovery plan
What can a business do if there are no disaster-recovery plans in place and a disaster
occurs?
Attacks on Computers and Networks
• Botnet• Denial-of-Service attack• Logic bomb• Trojan Horse• Malware on cell phones• Virus on router• iPod infected during manufacturing
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Identity / Information Theft
• Requests for information• Phishing (spoof E-mail)• Pharming (fake web site)• Auction fraud
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Real Web Site
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Fake Web Site
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Protection at Work
• No floppy / USB use• Secure access
– Physical– Logical
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Recent Problems
• Cyberbullying• Cyberstalking• Pornography• Child predators
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Internet Predators
Legal Protection
• Laws changing due to changing technology
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