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 include 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 Substitute 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 it

Requires both keys

Who Uses Encryption?

Banks Industry Professionals National ID cards Criminals .....

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 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

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 BUT

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

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

munitionscan’t export secure systems