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what is a public key encryption?? In public key encryption we have two keys: - one is public and another is private.We use these keys for secure communicating with each outher.Public key is used by sender to encrypt his message and private key is used by receiver to decript this message. Example :- Suppose I want to get message from many resources so  I will distribute public key to all the user who want to send me message and I keep private key to decrypt the message which user send to me.

what is PGP (Pretty Good Privacy) ??  Father of PGP :- Phil Zimmerman PGP is a encryption program that provides cryptographic privacy and authentication for data communication.It is the most popular standard for email encryption.

what is a RSA encryption ?? RSA : - Rivest-Shamir-Adleman (these are the name of RSA inventors.) RSA is a encryption algorithm which is used to send message securely in the internet.RSA is a public key algorithm widely used for secure data transmission.In public key algorithm we used two keys for data transmission : one is public and another is private key.We use public key for data encryption and private key for data decryption .  RSA is based on the principle that it is easy to multiply large numbers, but factoring large numbers is very difficult. In RSA, the public key is generated by multiplying two large prime numbers and  together, and the private key is generated through a different process involving  and . A user can then distribute his public key , and anyone wishing to send the user a message would encrypt their message using the public key. Algorithm of RSA :- Choose two large prime numbers P and Q such that P is not equals of Q. Calculate ...

what is Data Encryption Standard (DES)? Data Encryption Standard (DES) is a symmetric-key algorithm for the encryption of data.It is a outdated method for encrypting data.It uses a single private key for encryption and decryption of data.Data Encryption Standard (DES) is published by the National Institute of Standards and Technology (NIST).Data Encryption Standard (DES) is a block cipher it means that the data we do encrypt is encrypted in form of blocks. In DES we have a 64 bit plane text which converts into 64 bits cipher text after do DES encryption.

what is layer 2 tuning protocall(L2TP)?? L2TP is  a tuning protocall which is used to support VPN(virtual private network). L2TP is often employed by ISPs to allow VPN operations. It was devlop by two companies : -  Microsoft and Cisco and it was published in 1999. It was designed as a sort of successor to PPTP.

What is point to point tuning protocall(PPTP)? PPTP is a technique which is used to create a virtual private network(VPN) in which data can be transfer between one node to another safely.In PPTP we transfer data from one node to another with the help of tunnel so that no one can view or read the data. Example :- If a person is accessing the wifi then he also use the VPN PPTP .In this process the all online activity of user is encrypted.If a unknown person cracks the connection and wants to retrieve user data then it is not possible because all the data of the user is in tunnel.

what is Ciphertext ? The text which comes after the encryption of the plain text is called cipher text. Cipertext is that text which cames after the encryption of the plain text.The encrypted text is called cipher text. We can get back plain text to decrypt the cipher text which is the reverse of encryption.

Symmetric  key cryptography ?  Symmetric key cryptography is oldest method of encrypting the message.It is a simplest method that involves only one secret key.This secret key is a simple text like number,string,letter,etc. A simple example of symmetric key encryption is that suppose I want to send " hello " to someone then to encrypt it I will replace every text of this message into third text like for 'h' I will replace it with 'k' and 'e' with 'h' . so.. our message is : ----   Hello Encrypted message is :---khoor so if the unauthorised person read the encrypted message the he is not able to understand it .So our message is always be secure from unauthorized acess. Example :-  RC4, FISH, Py, QUAD, SNOW etc . Asymmetric key cryptography? Asymmetric encryption is also called public key cryptography.This is new technique instead of symmetric key cryptography.Asymmetric key cryptography uses two keys to encrypt the message .one is p...

What is Encryption?? Encryption is the process of converting plain text into secret formet.We use encryption to hide our data from unauthenticated persons.We use different cryptographic algorithm to encrypt out data such as SSH,MD5,etc.Generally we use encryption in sender side. What is Decryption? Decrytion is the process of converting encrypt code into plane text . It is the reverse process of encryption.We use decryption in receiver side. Difference between Encryption and Encryption :- Encryption is used to convert plain text into secret format whereas decryption is used to convert secret format into plain text. We use encryption and decryption to securely transmission of data.Sometimes we use a key which is used to encrypt and decript our data.Only that person use the data which has the key.

what is cryptography?? Cryptography is a method of converting or protecting our data or message into secret form so that it could not be in wrong hands.The only person which has the key only can read the message. The cryptography word is made of two words : - crypt and graphy . Crypt means hidden or vault and graphy means writing so that cryptography means that's the writing or message which is in hidden form. In cryptography we encrypt(convert our message into secret form) our message in secret form using different cryptography algorithm so that unautorised person could not read the message. After doing encryption we send data to receiver and in receiver already have a decription key so receiver decrypt(retrieve encrypt data in real form ) the message so that only receiver can read that message. Objectives of Cryptography :- 1 : Confidentiality :  Confidentiality means that the message will not be reached in hands of unauthorized person.Only the a...

What is Cyber Ethics ? Cyber ethics is the study of ethics related to computers, covering user's behavior and what computers are programmed to do, and how this affects individuals and society. With the increase of young children using the internet, it is now very essential than ever to tell children about how to properly operate the internet and its dangers. It is especially hard to talk to teens because they do not want to be lectured about what is right and wrong. They seem to think they have it all sorts out. That is why is it is important to instill appropriate cyber etiquette at an early age but if you haven’t there is still time to tell to your child. Issues in Cyber Ethics :- Copyrighting and downloading another's content:-  Downloading the copyright product from the internet is came into the cyber crime.We don't know that how much illegal is this product is that we only have to use it though it will present in any place . Hacking :- Stealin...