Cryptography
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Network security is important for business organizations and educational institutes to protect email communications, data distributions, stock trading, and distance learning from various threats like content theft, manipulation, masquerading, replay attacks, and denial of services. Cryptography provides security services like authentication, confidentiality, integrity, and access control through techniques like encryption, digital signatures, digital envelopes, and digital certificates to embed confidence in online activities like banking, trading, and purchases. Popular applications that use cryptography include PGP, IPsec, and SET, which aim to securely transmit information over the internet.
Cryptography
- 1. Network Security- A Need Business Organizations Educational Institutes E-mailing, Data Distributions Stock Trading Distance Learning
- 2. THREATS 1) Stealing out confidential content by third party. 2) Inter or Intra-organizational manipulations. 3) Masquerading threats. 4) Replay attacks. 5) Denial of services.
- 3. To understand the concept of cryptography and its security services. To bring out solution in the form of applications to uproot security threats. To understand working of various cryptography based applications. OBJECTIVE
- 4. Cryptography is a technology of hiding actual content in some form which is unintelligible. In other words, Cryptography is a method to enlock and unlock a document using a personal key. What is Cryptography?
- 5. Embed confidence in people: 1) to do online banking 2) to do online trading 3) to make online purchases with their credit cards. How ? With a assurance that account information or any critical information is secured through cryptographical services. Cryptography- The Back Bone
- 6. EXAMPLE Suppose you have a message as: “ I HAVE SENT YOU THREE CRORES” with a key = 3. Assign Numerical equivalent to each letter: N O P Q R S T U V W X Y Z 13 14 15 16 17 18 19 20 21 22 23 24 25 A B C D E F G H I J K L M 0 1 2 3 4 5 6 7 8 9 10 11 12
- 7. Now add your key to your message from assigned numerical values from table Key T =>19 + 3 = 11 => W (Converted letter) Entire converted message would appear as: “ I HAVE SENT YOU THREE CRORES” “ L KDYH VHQW BRX WKUHH FURUHV” Encrypted Message
- 8. SECURITY By CRYPTOGRAPHY Authentication Confidentiality Integrity Access Control Availability
- 9. PUBLIC KEY PRIVATE KEY Difference PRIVATE KEYS PUBLIC KEYS 1)Only one key is used for 1)Two keys are used,one for encryption & decryption. Encryption and another is used for decryption. 2)Private keys are shared. 2)Public key pair is only generated, not shared. 3)Known to only 3)One is publicly exposed communicating parties. & other is kept secret. TYPES OF KEYS
- 10. Model for Private key Algorithms Message Encrypting Procedure INETERNET DECRYPTING PROCEDURE Recovered Message Private Key Private Key Shared keys by sender and receiver At sender side At Receiver side
- 11. Model for pubic key algorithms Message Encryption Procedure INTERNET Decryption Procedure Recovered Message Key Pair Source Receiver’s Public key Exposed to public Receiver’s private key
- 12. It is a stream of bits appended to a document with the objective of providing: Integrity Origin assurance Parties Involved in the transaction process. Signer Verifier Arbitrator DIGITAL SIGNATURE
- 13. DIGITAL ENVELOPE An application to seal sender’s message in such a way that intended recipient can only open & read the message. Components: 1) Encrypted data 2) Encrypted key DIGITAL CERTIFICATES An application in which a central authority signs a sender’s message and receiver can verify it after receipt. It contains following information: 1)User Name 2)User’s Public key 3)Signature Algorithm Digital Signature Applications
- 14. PGP (Pretty Good Privacy) What is PGP? PGP is an open source freely available software package for e-mail security. Explosive Growth and Usage 1)Available free worldwide for different platforms. 2)Make organisational’s mailing system more secure. 3)Well acclaimed with strong encrypting algorithms & key management system. APPLICATIONS
- 15. What is IPSEC ? Capability that can be added to Internet protocol to enhace network security. Provides the capability to secure communication across a LAN or WAN users. IPsec encompasses mainly on authentication, confidentiality, and key management. IPSEC Security Service:
- 16. Usage of IPSec: Secure branch office connectivity over the Internet. Secure remote access over the Internet. Establishing extranet and intranet connectivity with partners. Enhancing electronic commerce security.
- 17. What is SET ? A open encryption and security specification designed to protect credit card transactions on the Internet. Key Features of SET: Confidentiality of Information Integrity of data Cardholder account authentication Merchant authentications Secure Electronic Transactions (SET)
- 18. SET PARTICIPANTS
- 19. Steps in Online Transaction The customer 1)Opens an credit card account. 2)Receives a certificate. 3) Verifies merchant. 4) Places an order. 5) Sends order & payment. 6)Requests payment authorization. 7)Confirms the order. 8)Provides the goods or service. 9)Requests payment. The Merchant
- 20. E-business dimensions are expanding day by day Its only cryptography which can provide immunity to those transactions which are likely to toll hundreds of billions of dollars per year. CONCLUSION