22 April

1. 22 April Final Deliverables and Presentations Privacy and Security

2. Final Deliverables:due at start of final

3. On your home page In a single easily visible box, links/directions Not in the box means not there Documentation Functional spec Design document User manuals • Project • Executable • Code • Presentation

4. Project Executable • Access • Desktop: instructions for download and install • These should be the instructions for any user, not just for me • Web-based: url and supported browsers • Log-ins • Login name and password if needed • If there is an administrator or super-user, I need an id with that privilege • Hardware needed to run • Give it to me after presentation or • Where in Sitterson I can get it

5. Project code • Where I can find it • If I need to be given access to it, do it • pozefsky@gmail.com or pozefsky@cs.unc.edu • How I can view it • Do I need to install any software? • Is there a preferred IDE or tool? • General description of who wrote which pieces

6. Documentation • List of user manuals • If they are part of your program (e.g., on-line help), explain how I find it • SINGLE web page or document that incorporates each of • Functional spec • Design document • Each user manual

7. Retrospective • Final essay • Team evaluation

8. Final Presentations:A Celebration of Your Achievement

9. The Plan • Final is 4-7 on Thursday, May 1 • Pizza dinner to be provided at 7 • Pot luck dessert • Each team has 20 minutes including set-up • Clients will be invited • Scheduling based on client availability and preference • Open to the public

10. Presentation Content • What the project is • Why it is important • How it was built • Platform • Architecture • (Interesting development aspects) • Process lessons: NOT personal • Most important piece: demo

11. Privacy

12. Aspects of Privacy • Freedom from surveillance • Control of our own information • Freedom from intrusion

13. Historical Basis of Privacy • Justice of Peace Act (England 1361) • Provides for arrest of Peeping Toms and eavesdroppers • Universal Declaration of Human Rights (1948) • No one shall be subjected to arbitrary interference with his privacy, family, home or correspondence, nor to attacks upon his honour and reputation. • European Convention on Human Rights (1970) • Everyone has the right to respect for his private and family life, his home and his correspondence.

14. Legal Realities of Privacy • Self-regulation approach in US, Japan • Comprehensive laws in Europe, Canada, Australia • European Union • Limits data collection • Requires comprehensive disclosures • Prohibits data export to unsafe countries • Or any country for some types of data

15. Implementing Privacy • Anonymity • Security • Transparency and Control: knowing what is being collected

16. Privacy and Trust • Right of individuals to determine if, when, how, and to what extent data about themselves will be collected, stored, transmitted, used, and shared with others • Includes • right to browse the Internet or use applications without being tracked unless permission is granted in advanced • right to be left alone • True privacy implies invisibility • Without invisibility, we require trust

17. Technologies • privacy aware technologies (reactive) • non-privacy-related solutions that enable users to protect their privacy • Examples • password and file-access security programs • unsubscribe • encryption • access control • privacy enhancing technologies (proactive) • solutions that help consumers and companies protect their privacy, identity, data and actions • Examples • popup blockers • anonymizers • Internet history clearing tools • anti-spyware software

18. Impediments to Privacy • Data collection and sharing • Cookies • Web site last year was discovered capturing cookies that it retained for 5 years • Sniffing, Snarfing, Snorting • All are forms of capturing packets as they pass through the network • Differ by how much information is captured and what is done with it

19. P3P • Platform for Privacy Preference • World Wide Web Consortium (W3C) project • Voluntary standard published as a “note” • Web site • Policy machine readable, structured • Browsers • Understand policy • Behave according to user’s preferences

20. Privacy and Wireless • “Wardriver” program: scans for broadcast SSIDs • broadcasting improves network access, but at a cost • once the program finds the SSID • obtains the IP address • obtains the MAC address • … • Lowe’s was penetrated this way • Stole credit card numbers

21. Security

22. Network Security “Using encryption on the Internet is the equivalent of arranging an armored car to deliver credit card information from someone living in a cardboard box to someone living on a park bench” – Gene Spafford (Purdue)

23. Attacks • Information Transmission • Information Systems

24. Message Message Secure Message Secure Message Information Transmission Attack Trusted Third Party arbiter, distributor of secret information Sender Receiver Secret Information Secret Information Security related transformation Information channel Opponent

25. Information Systems Attack Gate Keeper Data Software Opponent - hackers - software Access Channel Internal Security Control Gatekeeper – firewall or equivalent, password-based login Internal Security Control – Access control, logs, audits, virus scans etc.

26. Firewall Techniques • Filtering • Doesn’t allow unauthorized messages through • Can be used for both sending and receiving • Most common method • Proxy • The firewall actually sends and receives the information • Sets up separate sessions and controls what passes in the secure part of the network

27. DMZ: Demilitarized Zone • Arrangement of firewalls to form a buffer or transition environment between networks with different trust levels Fire wall Fire wall Internal resources Internet

28. Fire wall Fire wall Fire wall Internal resources Internet Three Tier DMZ Web Server App Server

29. Issues in Network Security • Physical and logical placement of security mechanisms • Effect of communication protocols • Encryption (cryptography) can provide several of the security services • Private key vs. public key • Distribution of secret information to enable secure exchange of information is important

30. Key Technologies • Encryption • Authentication

31. Encryption • All encryption algorithms from BC till 1976 were secret key algorithms • Also called private key algorithms or symmetric key algorithms • Julius Caesar used a substitution cipher • Widespread use in World War II (enigma) • Public key algorithms were introduced in 1976 by Whitfield Diffie and Martin Hellman

32. Security Level of Encrypted Data • Unconditionally Secure • Unlimited resources + unlimited time • Still the plaintext CANNOT be recovered from the ciphertext • Computationally Secure • Cost of breaking a ciphertext exceeds the value of the hidden information • The time taken to break the ciphertext exceeds the useful lifetime of the information

33. Private Key

34. Caesar Cipher • Substitute the letter 3 ahead for each one • Example: • Et tu, Brute • Hw wx, Euxwh • Quite sufficient for its time • High illiteracy • New idea

35. Enigma Machine(Germany, World War II) • Simple Caesar cipher through each rotor • But rotors shifted at different rates • Roller 1 rotated one position after every encryption • Roller 2 rotated every 26 times… http://www.trincoll.edu/depts/cpsc/cryptography/enigma.html

36. Types of Attacks • Ciphertext only • adversary has only ciphertext • goal is to find plaintext, possibly key • Known plaintext • adversary has plaintext and ciphertext • goal is to find key • Chosen plaintext • adversary can get a specific plaintext enciphered • goal is to find key

37. Attack Mechanisms • Brute force • Statistical analysis • Knowledge of natural language • Examples: • All English words have vowels • There are only 2 1-letter words in English • High probability that u follows q • …

38. Private Key Cryptography • Sender, receiver share common key • Keys may be the same, or trivial to derive from one another • Sometimes called symmetric cryptography or classical cryptography • Two basic types • Transposition ciphers (rearrange bits) • Substitution ciphers • Product ciphers • Combinations of the two basic types

39. DES (Data Encryption Standard) • A block cipher: • encrypts blocks of 64 bits using a 64 bit key • outputs 64 bits of ciphertext • A product cipher • performs both transposition (permutation) and substitution on the bits • Considered weak • Susceptible to brute force attack • http://www.tropsoft.com/strongenc/des.htm

40. History of DES • IBM develops Lucifer for banking systems (1970’s ) NIST and NSA evaluate and modify Lucifer (1974) • Modified Lucifer adopted as federal standard (1976) • Name changed to Data Encryption Standard (DES) • Defined in FIPS (46-3) and ANSI standard X9.32 • NIST defines Triple DES (3DES) (1999) • Single DES use deprecated - only legacy systems. • NIST approves Advanced Encryption Std. (AES) (2001) • AES which will replaces DES and 3DES.

41. Cracking DES • 1998: Electronic Frontier Foundation cracked DES in 56 hrs using a supercomputer • 1999: Distributed.net cracked DES in 22 hrs • For an investment of $1 million for specialized hardware, DES can be cracked in less than an hour.

42. Public key

43. Public Key Cryptography • Two keys • Private key known only to individual • Public key available to anyone • Public key, private key inverses • Confidentiality • encipher using public key • decipher using private key • Integrity/authentication • encipher using private key • decipher using public one

44. Public Key Requirements • Computationally easy to encipher or decipher a message given the appropriate key • Computationally infeasible to derive the private key from the public key • Computationally infeasible to determine the private key using a chosen plaintext attack

45. RSA • Public key algorithm described in 1977 by Rivest, Shamir, and Adelman • Exponentiation cipher • Relies on the difficulty of factoring a large integer • RSA Labs FAQ document http://www.rsasecurity.com/rsalabs/node.asp?id=2152

46. Summary • Private key (classical) cryptosystems • encipher and decipher using the same key • Public key cryptosystems • encipher and decipher using different keys • computationally infeasible to derive one from the other

47. Authentication • Assurance of the identity of the party that you’re talking to • Primary technologies • Digital Signature • Kerberos

48. Digital Signature • Authenticates origin, contents of message in a manner provable to a disinterested third party (“judge”) • Sender cannot deny having sent message (service is “nonrepudiation”) • Limited to technical proofs • Inability to deny one’s cryptographic key was used to sign • One could claim the cryptographic key was stolen or compromised • Legal proofs, etc., probably required • Protocols based on both public and private key technologies

49. RSA for Digital Signature • Private key to sign • Public key to validate

50. Kerberos • Authentication system • Central server plays role of trusted third party • Ticket (credential) • Issuer vouches for identity of requester of service • Authenticator • Identifies sender • User must • Authenticate to the system • Obtain ticket to use server S • Problems • Relies on synchronized clocks • Vulnerable to attack