Cyber Security chapter4
Data Protection Techniques
.Cryptography: Cryptography means secrete writing
mechanisms: - symmetric-key ciphering, asymmetric-key ciphering, and
.hashing
.Steganography: Steganography means covered writing
:Objective of Steganography
It hides information either for secrecy or to protect copyright, prevent
.tampering or add extra information
Power and limitations of cryptography
-.It hides the meaning of data, but does not hide the data itself
-The task of encryption methods is to start with plain, readable data
.and scramble it so it becomes an unreadable ciphertext )plaintext(
Encryption method must specify how the ciphertext can be -
.decrypted back into the plaintext it came from
.Cryptography is a useful tool in achieving confidentiality-
Even the strongest cryptographic methods cannot prevent a virus-
.from damaging data or deleting files, and DoS attacks
,Three Components of the Security System
A security-related transformation of information to be sent. -1
:Examples include
.Encryption of a message to be unreadable by opponent -
.Addition of a code to verify the identity of the sender -
Some secret information shared by the two principals and unknown -2
.to the opponent
.An example is an encryption key-
A trusted third party for distributing secret information to the two -3
.principals
, Four Basic Security Tasks
Design an algorithm for performing the security-related -1
.transformation
.Generate the secret information to be used with the algorithm -2
Develop methods for the distribution and sharing of the secret -3
.information
Specify a protocol for principals to use security algorithm and secret -4
.information to achieve security service
Data Protection Techniques
.Cryptography: Cryptography means secrete writing
mechanisms: - symmetric-key ciphering, asymmetric-key ciphering, and
.hashing
.Steganography: Steganography means covered writing
:Objective of Steganography
It hides information either for secrecy or to protect copyright, prevent
.tampering or add extra information
Power and limitations of cryptography
-.It hides the meaning of data, but does not hide the data itself
-The task of encryption methods is to start with plain, readable data
.and scramble it so it becomes an unreadable ciphertext )plaintext(
Encryption method must specify how the ciphertext can be -
.decrypted back into the plaintext it came from
.Cryptography is a useful tool in achieving confidentiality-
Even the strongest cryptographic methods cannot prevent a virus-
.from damaging data or deleting files, and DoS attacks
,Three Components of the Security System
A security-related transformation of information to be sent. -1
:Examples include
.Encryption of a message to be unreadable by opponent -
.Addition of a code to verify the identity of the sender -
Some secret information shared by the two principals and unknown -2
.to the opponent
.An example is an encryption key-
A trusted third party for distributing secret information to the two -3
.principals
, Four Basic Security Tasks
Design an algorithm for performing the security-related -1
.transformation
.Generate the secret information to be used with the algorithm -2
Develop methods for the distribution and sharing of the secret -3
.information
Specify a protocol for principals to use security algorithm and secret -4
.information to achieve security service
