steganography

04/08/23 1

Encryption, Cryptography, and Steganography:

An introduction to coded communications

04/08/23 2

Agenda

• Introduction to Encryption• Cryptography• Steganography• Surveillance• Summary

04/08/23 3

Encryption

• The translation of information into a secret code

• Typically utilizes secret keys or passwords

• Security that is exercised heavily in E-Commerce transactions and authentication

04/08/23 4

Cryptography

• The science of information security

• Includes analog methods: ex. microdots, merging words with images

• Scrambling plaintext into ciphertext

04/08/23 5

Example of microdots...

From this

.

To this...

Example magnified 300X

04/08/23 6

Cryptography

Plaintext encryption---------> ciphertext

decryption--------->

Plaintext

04/08/23 7

Types of Cryptography

• Hash Functions: no key, “digital fingerprint” of a larger document

• Secret Key Cryptography (symmetric encryption): one key

• Public Key Cryptography: two keys - public & private

04/08/23 8

Use of Cryptography

• Security for corporate and government information.

• Privacy• Digital signatures

and authentication

• Currently no restrictions on use in the United States

• Possible criminal use: impede investigation

• Rumored to be used in recent terrorist attacks

04/08/23 9

Steganography

• Steganography is the art of hiding a secret message inside another message.

• Digital watermarking and fingerprinting of audio and video.

• Not intended to replace cryptography, but supplement it.

04/08/23 10

Steganography: an example...

• Computer files

contain unused

or insignificant

areas of data

• Hard to detect

• Special

software to

read

04/08/23 11

Steganography: Other Examples

04/08/23 12

FBI Methods of Policing Encryption

Carnivore (DCS1000)

“Magic Lantern”

04/08/23 13

Carnivore

• File “sniffer”• Detects IP

Packets• Imperfect

against many encryption methods

• Controversial

04/08/23 14

“Magic Lantern”

• Based on Carnivore• Trojan Horse program• Installs on a suspect’s machine

and obtains encryption keys

• Reads keystrokes• Ethics and implementation

debated

04/08/23 15

Conclusion

• Encryption currently has many

legitimate and necessary uses

• Government has become more

concerned about its applications

• Future…?

04/08/23 16

Questions & Answers

This presentation is also on the Web at:

Turbokinetic.com/files.html