CSCU Module 04 Data Encryption

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Data Encryption

Simplifying

Security.

Module 4

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Roughly

Roughly 4040 percentpercent of of ITIT workersworkers believebelieve theythey couldcould holdhold anan employer’semployer’s networknetwork hostagehostage — even— even afterafter leaving

leaving thethe companycompany —— by bywithholdingwithholdingororhidinghidingencryptionencryptionkeyskeys,, accordingaccording toto aa recentrecent surveysurvey of of 500500 IT

IT securitysecurity specialists.specialists. The

The study,study, releasedreleased Monday,Monday, MayMay 23,23, alsoalso revealedrevealed thatthat aa thirdthird of of surveysurvey respondentsrespondents werewere confidentconfident that

that theirtheirknowledgeknowledgeandandaccessaccesstotoencryptionencryptionkeyskeysandandcertificatescertificatescouldcouldbringbringaacompanycompanytotoaahalthalt

with

with littlelittle effort.effort. ConductedConducted inin AprilApril 2011,2011, thethe surveysurvey waswas sanctionedsanctioned byby Venafi,Venafi, aa networknetwork keykey andand encryption

encryption provider.provider.

40

40 Percent

Percent

of

IT

Workers

Could

Hold

Employer

Networks

Hostage,

Survey

Finds

“It’s

“It’s aa shameshame thatthat soso manymany peoplepeople havehave beenbeen soldsold encryption

encryption butbut notnot thethe meansmeans oror knowledgeknowledge toto manage

manage it,”it,” saidsaid Jeff Jeff Hudson,Hudson, CEOCEO of of Venafi,Venafi, inin aa statement.

statement. “IT“IT departmentsdepartments mustmust tracktrack wherewhere thethe keys

keys areare andand monitormonitor andand managemanage whowho hashas accessaccess toto them.them. ... It’sIt’s nono longerlonger rocketrocket science.science. YYetet recent,recent, costly

costly breachesbreaches atat Sony,Sony, EpsilonEpsilon andand elsewhereelsewhere reinforcereinforce thethe needneed forfor bothboth moremore encryptionencryption andand effective

effective management.”management.”

May May 23,23, 20112011

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Module Objectives

Common Terminologies

What Is Encryption?

Objectives of Encryption

Types of Encryption

Encryption Standards

Symmetric vs. Asymmetric

Encryption

Usage of Encryption

Digital Certificates

Working of Digital Certificates

Digital Signature

How Digital Signature Works?

Cryptography Tools

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Cipher Text

Cipher text is encrypted and unreadable until it is decrypted to

plaintext with a key

Encryption Key

An encryption key is a piece of information that is used to

encrypt and decrypt data

Common Terminologies

Plaintext

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What Is Encryption?

Plain text (‘Morpheus’)

Bob

Alice

Encryption is the process of

converting data into a cipher text that cannot be

understood by the unauthorized people

To read an encrypted file, you must have

access to a secret key or password that

enables you to decrypt it

Encryption is used to

protect sensitive information during transmission and storage

Encrypted DATA is received by Alice

Alice receives the plain data after

decryption Encrypted DATA

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Data Integrity

Authentication

Non

_‐

repudiation

The receiver of a message can check whether the

message

was modified during transmission

, either accidentally or deliberately

The receiver of a message can verify the origin of the message No other user should be able to send a message to the

recipient as the original sender (data origin authentication)

The sender of a message

cannot deny

that he/she has sent the message

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Usage of Encryption

It helps tosafely store sensitive information on a computer or external storage media

Encryption is usedto protect user credentials such as user name and passwords

Encryption provides assurance of a sender’s identity

It is also used as a resource for web

_‐

based information exchange toprotect

important information such as credit card numbers Encryption provides asecure

medium for users to connect to their friends’ or employees’ network from outside of the home or office

It provides ahigher level of trust when receiving files from other users by ensuring that the source and contents of the message are trusted

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Types of Encryption

Symmetric Encryption

Symmetric encryption (secret

_‐

key, shared

_‐

key, and private

_‐

key) uses the same key for

encryption and decryption

Asymmetric Encryption

Asymmetric encryption (public key) uses different encryption keys for encryption and decryption. These keys are known as public and private keys

Hash Function

Hash function (message digests or one

_‐

way encryption) uses no key for encryption and decryption Dear John, This is my A/C number 7974392830 Dear John, This is my A/C number 7974392830 Guuihifhofn kbifkfnnfk Nklclmlm #^*&(*)_(_ Encryption Decryption

Plain text Cipher text Plain text

Symmetric Encryption Asymmetric Encryption Dear John, This is my A/C number 7974392830 Dear John, This is my A/C number 7974392830 Guuihifhofn kbifkfnnfk Nklclmlm #^*&(*)_(_

Plain text Cipher text Plain text Encryption Decryption

Hash function

Plain text Cipher text

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Symmetric vs. Asymmetric Encryption

Symmetric Encryption

Asymmetric Encryption

Symmetric encryption

uses only one key

for both encryption and decryption

The key

cannot be shared freely

Symmetric encryption requires that both

the sender and the receiver know the

secret key

Using symmetric encryption, data can

be encrypted faster

This algorithm is less complex and faster

Symmetric encryption

ensures

confidentiality and integrity

Asymmetric Encryption uses a

public key

for encryption and a

private key for

decryption

In asymmetric encryption, the public key

can be

freely shared, which eliminates the

risk of compromising the secret key

The encryption process using Asymmetric

Encryption is

slower and more complex

Asymmetric encryption

ensures

confidentiality, integrity, authentication,

and non

_‐

repudiation

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Encryption Standards

Data Encryption

Standard (DES)

Advanced Encryption

Standard (AES)

Data Encryption Standard (DES) is the name of the Federal information Processing Standard (FIPS) 46

_‐

3, which describes the data encryption algorithm (DEA)

The DEA is a symmetric cryptosystem originally designed for implementation in hardware

DEA is also used for single

_‐

user encryption, such as to store files on a hard disk in encrypted form

Advanced Encryption Standard (AES) is a

symmetric

_‐

key encryption

standard adopted by the U.S. government It has a

128 _‐

bit

block size, with key sizes of 128, 192 and 256 bits,

respectively, for AES

_‐

128, AES

_‐

192 and AES

_‐

256

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Digital Certificates

Details of owner’s public key

Digital signature of the

CA (issuer)

Serial number of digital

signature

Owner’s name

Expiration date of

public key

Name of the Certificate

Authority (CA) who issued the

digital certificate

A digital certificate is an electronic card that provides credential information while

performing online transactions

It acts as an electronic counterpart to a drivers license, passport, or membership

card and verifies the identity of all users involved in online transactions

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Private Key

Public Key  Validation of electronic signature

 Inquires about public key certificate validity to validation authority

Determined Result Public Key

Certificate

Message in public key certificate signed with digital signature

User

Public Key Certificate

Updates Information

User Applies for Certificate

Registration Authority (RA)

Request for Issuing Certificate

Validation

Authority (VA)

Certification

Authority (CA)

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Digital Signature

Digital signature implements asymmetric cryptography to simulate the security

properties of a signature in digital, rather than written form

Digital signature schemes involve two encryption keys: a private key for signing the

message and a public key for verifying signatures

Digital standards follow the open standards as they are not tied to an individual or

manufacturer

It is often used to implement electronic signatures and can be used by any type of

message

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How Digital Signature Works

SIGN SEAL DELIVER ACCEPT OPEN VERIFY

Encrypt message using one‐time symmetric key

Encrypt the symmetric key using recipient’s PUBLIC key

Mail electronic envelopes to the recipient Confidential Information Rehash the message and compare it with the hash value attached with the mail Recipient decrypt one‐time symmetric

key using his PRIVATE key

Decrypt message using one‐time symmetric key

Hash value Sender signs hash code using his PRIVATE key

Append the signed hash code to message

Unlock the hash value using sender’s PUBLIC key

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Module Flow

Encryption

Types of

Encryption

Standards

Digital

Certificates

Digital

Signature

Cryptography

Tools

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Cryptography Tool: TrueCrypt

http://www.truecrypt.org

TrueCrypt creates avirtual encrypted disk within a file and mounts it as a real disk

Encrypts anentire partition or storage device such as USB flash drive or hard drive

Encrypts apartition or drive where Windows is installed (pre

_‐

boot authentication)

Encryption is automatic, real

_‐

time (on

_‐

the

_‐

fly), and transparent

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PixelCryptor

http://www.codegazer.com

Folder Lock

http://www.newsoftwares.net

EncryptOnClick

http://www.2brightsparks.com

Cryptainer LE

http://www.cypherix.co.uk

SafeHouse Explorer

http://www.safehousesoftware.com

Advanced Encryption Package

http://www.intercrypto.com

AxCrypt

http://www.axantum.com

Kruptos 2 Professional

http://www.kruptos2.co.uk

Cryptography Tools

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Module Summary



Encryption is the process of converting data into a cipher text that cannot be understood

by the unauthorized people



Symmetric encryption uses only one key for both encryption and decryption, whereas

asymmetric encryption uses a public key for encryption and a private key for decryption



Encryption provides a higher level of trust when receiving files from other users by

ensuring that the source and contents of the message are trusted



A digital certificate is an electronic card that provides credential information when

performing online transactions

