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COSC1078 Introduction to Information Technology Lecture 21 Internet Security

James Harland james.harland@rmit.edu.au. COSC1078 Introduction to Information Technology Lecture 21 Internet Security. Introduction to IT. 1 Introduction 2 Images 3 Audio 4 Video WebLearnTest 1 5 Binary Representation Assignment 1 6 Data Storage 7 Machine Processing

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COSC1078 Introduction to Information Technology Lecture 21 Internet Security

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  1. Intro to IT James Harland james.harland@rmit.edu.au COSC1078 Introduction to Information TechnologyLecture 21Internet Security

  2. Intro to IT Introduction to IT 1 Introduction 2Images 3Audio 4Video WebLearnTest 1 5 Binary Representation Assignment 1 6 Data Storage 7Machine Processing 8 Operating Systems WebLearn Test 2 9 Processes Assignment 2 10 Internet 11Internet Security WebLearn Test 3 12Future of IT Assignment 3, Peer and Self Assessment

  3. Intro to IT Overview • Questions? • Assignment 3 • Peer and Self Assessment • Internet Security • Questions?

  4. Assignment 3 Reflect Answer reflection questions from tutorials See last lecture for ideas Research Write about a particular IT topic of your choice (5-6 paragraphs) electronic voting, information security, 3D user interfaces, digital music, digital video, electronic commerce, natural language processing, DNA computing, quantum computing, cryptography, malware detection and removal, Moore's Law, green computing, … Lecture 21: Internet Security Intro to IT

  5. SE Fundamentals Self and Peer Assessment • How well has each person contributed to the group? • Evaluated over the entire semester • Assessed on process, not product • Work out a grade for each person (CR, DI etc) • Then convert this to a mark out of 20 • Submit list of marks to tutor with justifications • Repeat previous step until the tutor is satisfied • See guidelines in Blackboard material

  6. Internet Hi Dad! Listen! Hi Dad! Listen! Lisa? Lisa? Lecture 19: Internet: Images Intro to IT

  7. Internet Structure 2 1 3 4 Application Mordor sucks! Mordor sucks! Application 1Mor 2dor 1Mor 2dor Transport Transport 3suc 4ks! 3suc 4ks! 1 2 3 4 Network 3 1 Network 2 4 9 5 6 2 9 5 6 2 Link Link 3 2 4 1 Lecture 21: Internet Security Intro to IT

  8. Internet Structure 1 1Mor 6 6 Lecture 21: Internet Security Intro to IT

  9. Internet addresses Unique 32-bit identifier (up to 4,294,967,296) Soon to become 128-bit identifier Managed by Internet Corporation for Assigned Names and Numbers (ICANN) ISPs get “blocks” of addresses 32-bit string represented as N1.N2.N3.N4 where Ni is in the range 0..255 17.12.25.0 means 00010001000011000001100100000000 Lecture 21: Internet Security Intro to IT

  10. Internet addresses Dotted decimal notation is still not very kind to humans … www.sludgefacethemovie.com -> ??.??.??.?? Translation done by name servers which look up the Domain Name System (DNS) Domains such as rmit.edu.au can be structured by the domain owner (eg goanna.cs.rmit.edu.au) Lecture 21: Internet Security Intro to IT

  11. IPv4 vs IPv6 Internet Protocol version 4 (used since 1981) 32-bit addresses Can handle “only’’ 4,294,967,296 unique addresses Exhausted in February 2011 IPv6 uses 128-bits addresses IPv6 can handle “only” 3.4×1038addresses IPv5 didn’t change the IPv4 address space and wasn’t successful for other reasons … Lecture 21: Internet Intro to IT

  12. Intro to IT Internet Security pass word fire spam wall patch key logger war virus driving Trojan horse worm phishing proxy

  13. Security vs access It is always atrade-off(a balance between two competing forces) More security means less access More access means less security Redundancy can be either fatal or vital Nothing is perfect!

  14. Freedom vs security `Everything which is not forbidden is allowed’ -- Principle of English Law `Everything which is not allowed is forbidden’ -- Common security principle `Anything not mandatory is forbidden’ -- “military policy” `Anything not forbidden is compulsory’(??) — T.H. White (The Once and Future King)

  15. Passwords Should be: Long (8 characters or more) Not obvious or from a dictionary Contain capitals, numerals and non-alphanumeric characters (!&^*$@.,’[]{}? …) Recorded securely somewhere Transmitted in encrypted form only Older programs such as FTP, Telnet transmit this in plaintext … Lecture 21: Internet Security Intro to IT

  16. Firewalls Device which limits internet connections Limit network uses to only approved ones Prevent malicious software reporting information Prevent outside attacks May need to have ports opened to allow applications to work Only work on applications, not on content Lecture 21: Internet Security Intro to IT

  17. Proxy servers All internet traffic routed via proxy server Acts as an internet gateway Once proxy is secure, so is network Can filter content Can cache content Often used with a firewall in a corporate environment Lecture 21: Internet Security Intro to IT

  18. Wardriving Driving around to find a vulnerable wireless signal Find a wireless connection that doesn’t require a password(so add one to yours if you haven’t!) Attack systems that use a default admin login name and password (change yours!) Snoop on transmissions which are not encrypted (encrypt yours!) Using a MAC address whitelist means only specified devices can connect to your router Lecture 21: Internet Security Intro to IT

  19. Viruses,Worms,Trojans Virus:self-replicating program that attaches itself to files and is spread when they are transferred Worm:self-replicating program that pro-actively spreads itself Trojan horse:a program that appears legitimate but is in fact malicious Lecture 21: Internet Security Intro to IT

  20. Malware and Spyware Malicioussoftware: Hidden mail server Key logging (to capture passwords) Enable machine takeover Direct traffic to particular web sites Analyse behaviour Act as a proxy … Lecture 21: Internet Security Intro to IT

  21. Denial of service Prevent network from working normally Flood a server with ‘invalid’ inputs Use a network of compromised machines to generate an overwhelming number of requests (Conficker?) Such zombie machines can form a botnet, which then attack a particular server Lecture 21: Internet Security Intro to IT

  22. Tricking the user Users are often the weakest link in security Email attachments containing trojan horses ‘Phishing’ Malicious web pages Malicious documents (macros in spreadsheets) Account stealing (via key logging) Scams (‘I have $10 million to import’, ‘You have just won the lottery’, …) Lecture 21: Internet Security Intro to IT

  23. Protecting your system Keep up to date with patches (Windows update, Software update) Use a firewall Use anti-virus software and keep it up to date Use anti-spyware tools Filter email for spam and suspicious messages Be aware of ‘fake alerts’ Lecture 21: Internet Security Intro to IT

  24. Intro to IT Conclusion • Work on Assignment 3 • Check whether your security defenses are up to date

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