4. Contd…..
• Network Security
What is Network?
About Network Security
Security Goals
Objective Of Security
Data Security
Problems & Attacks
Threats
Conclusion
5. CRYPTOGRAPHY
It is derived from the Greek word that meant for secret
writing.
Cryptography is a Software or hardware programs use
Mathematical Functions , Formulas(Algorithms) to
change text from one from to another.
Cryptography is the science and art of transforming
messages to make them secure and immune to attacks.
It provides Confidentiality, Integrity, Accuracy.
Applications of cryptography includes ATM cards,
Computer passwords .
It’s very useful to our Army & Police network to transfer
confidential data
6. TECHNIQUES
The data is transferred by applying two
techniques
1. Encryption
2. Decryption
Encryption: The way of converting the plain text
to the Cipher text by the means of few keys is
called as the” Encryption”.
Decryption: The way of converting the Cipher text
to the Plain text by the use of keys that are
suitable to it is called as ”Decryption”.
9. SYMMETRIC KEY CRYPTOGRAPHY
The implementation of a simple
cryptography using single key is done by
the Secret-key algorithms.
Also known as SECRET KEY
CRYPTOGRAPHY. Sender & Receiver
uses same key and an Encryption/
Decryption Algorithm to Encrypt /
Decrypt data.( i.e ) The Key is shared
This can be done by p-box, s-box and
product cipher
12. SUBSTITUTION CIPHER
Replacing of each letter
or group of letter or group of letters of
plain text into cipher text
by another letter is called
as “Substitution cipher”.
The substitution may be:
Monalphabetic Substitution
Polyalphabetic Substitution
13. TRANSPOSITION CIPHER
The change offered in
The position of the text
i.e. By jumbling the
Words is called as
” Transposition Cipher”.
And the technique used
here is termed as ”Mass
Technique”.
14. ASYMMETRIC KEY CRYPTOGRAPHY
Also known as PUBLIC KEY
CRYPTOGRAPHY . Sender & Receiver uses
different keys for Encryption & Decryption
namely PUBLIC & PRIVATE respectively.
15. RSA ALGORITHM
RSA is derived from the names of the
discoverers named Rivest, Shamir, Adleman.
The RSA algorithm is one of the widely used in
the key algorithms.
1. The main function of this algorithm is providing
approach to public key cryptography &
Encryption
2. In this the CIPHER TEXT are the integer’s
between 0 and n-1
16.
17. APPLICATIONS
• Defense Services
• Secure Data Manipulation
• E- Commerce
• Business Transactions
• Internet Payment Systems
• User Identification Systems
• Access Control
• Data Security
18. WHAT IS NETWORK ?
A network is an interconnection
or a media between two or
more systems to share
information among them.
The various threats caused to
network are:
* Remote login
* Operating System Bugs
*Spams & viruses etc.
19. NETWORK SECURITY
• The security provided to the
network is called network
security which at present is
looming on horizon as a
massive problem.
• There are two kinds of Network Security mainly
as:
Transit security : It just encrypts the packets to
be transferred
Traffic Security: It acts just as a screen between
hosts & remote sites
21. OBJECTIVE OF SECURITY
To avoid data threats
To avoid denial of services
To secure our data from masquerades
To safeguard our data’s from traffic
analyzer
To not to make message for the third
person available
22. PASSWORD AUDITING
Should not be in uppercase
Must have at least 8 characters
Must include alphabets, numeric keys & special
characters
Password should not be the name of the user,
dictionary word etc.,
It must be updated at least once a month
23. DATA SECURITY
• To monitor the user’s
ACCESS CONTROLS
• System that are connected in network
must be protected with firewalls
• To protect the integrity & availability of
the institution’s information asset’s
24. PROBLEMS & ATTACKS
There are few intertwined areas in network
security as:
Secrecy
Authentication
Non-Repudiation
Integrity control etc.
The threats are classified into two categories:
Passive Attacks: A passive attack is one in
which the attacker eavesdrops and listens to the
message but can’t modify the message.
25. • Active Attacks: An active attack is one in
which the attacker modifies, deletes,
replay or introduce new messages into the
stream of message.
THREATS
26. CONCLUSION
However, through this Cryptography &
Network Security We Successfully
hiding and secure the data with the help
of Encryption & Decryption.
27. “ For every lock there is a key…..
It is better to keep safe your lock than
the key”