Wiretapping and Encryption More Week 5 cont.

Early Forms of Wiretapping Party Lines Human Operators

Wiretapping Today Federal and state law enforcement Businesses Private Detectives Political Candidates ......

Cellular Phones Can be tapped with over-the-counter devices

Standard Phones Easily tapped if signal travels by microwave or satellite Government has secured phones

Legal Mandates 1937 - Supreme Court rules that wiretapping is illegal 1968 - Congress explicitly allowed it by law enforcement agencies needs court order Electronic Communications Privacy Act includes new technologies

Cryptography - Making and breaking of ciphers Translation of the original message into a new incomprehensible one by a mathematical algorithm using a specific KEY Plaintext - a message or data Ciphertext - encrypted text Decryption - decipher back to plaintext

Encryption Includes: Coding scheme or cryptographic algorithm Specific sequence of characters key used by the algorithm

Examples Cereal box codes Substitution cipher Cryptoquip in newspaper

Variations - Symmetric Use the same key to encrypt and decrypt (secret key) Requires a more secure system to send the key than the system itself

Variation - Asymmetric Use a key (public key) to encrypt a message Another (private key) to decrypt the message

Who Uses Encryption? Banks Industry Professionals National ID cards Criminals Government .....

Industrial Espionage Knowledge of a company’s cost and price structure Market research Strategic plans Order and customer lists Insider information

Professionals Cellular telephones and electronic mail unencrypted data on machines

Criminals Cryptography allows criminals to keep their identities a secret Provides security to law breakers Allows anonymity Don’t use systems that leave trails

Reliability The longer the key has remained unbroken, the stronger it is likely to be The longer the key is in use, the more likely someone will be able to discover it larger amount of info will be compromised change key frequently

Algorithms available DES - Data Encryption Standard Developed by IBM in the 1970’s Adopted as a Federal Information Processing Standard Uses a 56 bit key Has been broken easily To extend life - extend key to 128 bits or triple DES

RSA algorithm Used in public key cryptography Patented in US Based on multiplication of large prime numbers

PGP - Pretty Good Privacy Based on RSA Used for protecting E-Mail And Online Credit Card transactions

New Controversies 1991 - Senate Bill - Government wants to be able to intercept any message and be able to decode it as well - not passed FBI and wiretapping - Telephony bills FBI and Clipper Chip

Benefits of Government Intervention Aid law enforcement in protecting us from criminals and terrorists

Problems Threats to privacy global competitiveness civil liberties

Communications Assistance for Law Enforcement Act 1994 to and from Requires that telecommunications equipment be designed so govt. can: intercept all wire and electronic communic. Intercept comms from mobile users Obtain call-identifying info phone numbers Have info transmitted to a specific location Government will help foot the bill

Arguments for... Protection from terrorists and criminals FBI wants no new privileges BUT Necessity has not been justified Expense and other problems outweigh the benefits There has never been a guarantee of interception of private messages before

NEED? Wiretaps are less useful than informants, witnesses, etc. BUT 90% of terrorist cases used wiretaps Industry claims full compliance with FBI Continued cooperation is not guaranteed

COST? A lot more than government is giving Will save money in fines, forfeitures, prevented economic loss Used only in a subset of investigations Could use the money on other technologies

Innovation and global competitiveness Stifle or delay new technologies economic costs prevent new technologies’ implementation Damage to US competitiveness in global markets due to reduced security and privacy

Protection from Dossier Society Digital cash made possible by public key encryption Secure financial transactions without a credit card or checking account number

E-Cash (like PayPal) No link between payer and recipient Convenience of credit card Anonymity of cash Use on Internet for ordinary shopping Can transfer credentials Can prevent duplicate cash files Back up at home in case card is lost or stolen

E-Cash continued Not easy to form a consumer profile or dossier Prevent fraud and forgery Protect privacy from mailing lists More control over personal information

History of Encryption Secret - NSA National Security Agency can do anything has powerful computers - break ciphers and create ciphers monitors all communications between US and other countries

Government Interception NSA censored research controlled researchers Export restrictions munitions can’t export secure systems