Cryptography in computer network | Cryptography in Information Security

Cryptography in computer network | Cryptography in Information Security 

        Hello friends. Welcome to Digital World the subject is cryptography. Cryptography is such a way through that we are able to convert plain text to cipher text. And cipher text is reborn to plain text once more. currently you need to be thinking the that means of plain text and Cipher text. Plain text may be a message, a normal, message that anyone will browse and perceive. That what's written during this message? however cipher text is such a message. We can say a secret message. That anyone will browse however cannot perceive. that means the message may be seen. however what's written, the that means of that. which will ne'er be understood. thus why will we convert from plain text to cipher text. we tend to use cryptography to realize confidentiality. Confidentiality. once we remark network security. there's one vital construct in network security. Of state. Confidentiality, Integrity, and handiness. Integrity, and handiness. currently the C in state is. Confidentiality

Confidentiality suggests that. What we tend to perceive from confidentiality that nobody may take my message. nobody ought to take my message. that means if i'm causing a message from here. to a different receiver let’s say receiver is sitting away. Receiver is sitting kilometre away. currently somebody is taking my message on the method. he's AN attempt|attempting} to hack my message in an unauthorized method. however it doesn't mean that your confidentiality is broken. Confidentiality becomes zero. No. Anyone will take the message. as a result of what's net on net all the devices area unit connected in a very vulnerable manner. Vulnerable implies that a person with some data. If he is aware of the ability of. Hacking He will take your packet. however taking the packet doesn't mean. Taking the info doesn't mean. That he will browse the info. If the person may browse the info. perceive that. Then you'll be able to say confidentiality zero. however if on the method a person trace your packet. Trace doesn't implies that he can perceive what's written within the packet. so is that the that means of confidentiality. currently we tend to area unit talking that the sender needs to send an evident text. Plain text suggests that a traditional message that anyone will browse. it's a traditional message. currently if send that message to receiver. there's no dedicated wire here. we do not have a fanatical wire on net. as an instance I actually have to send a message from place to American state. Send AN email. thus is there a fanatical line from current place to American state. a fanatical link.No.We area unit victimisation net. that means once the message exits our machine.

 On that router, on that node will it go. that means this web log, this medium is unsecure. It is. Unsecure thus AN unsecure medium, unsecure channel. we tend to area unit causing a message on. Any unauthorized person will Take that message. thus there's no drawback of confidentiality here. It will take any. Message however if we tend to send that message as plain text. Anyone will browse that message. comprehend it. however we do not wish this. For that we tend to use cryptography. What will we do? Sender, before causing the plain text use cryptography methodology. In cryptography we tend to use several algorithms. i will be able to tell you this algorithms. What do these algorithms do? The most vital half here is vital. They use a key. Lock, the lock that we tend to place in our house. what's that lock it get locks, and find opened with a key. so is that the key. they're going to lock with this key. once applying the lock. It becomes cipher text. Cipher text may be a secret message that no one will browse. nobody will perceive. once we can send that message on this channel. On this unsecured channel. If we send. Then anyone will take that on the method. however that M isn't That M has become M'.Because we tend to aren't causing M because it is. Not causing plain text because it is. we tend to area unit causing once changing into cipher text. thus M becomes .Let's say M'. that the unauthorized individual that is reading this on the method. He thinks that sender is causing M'. however we tend to area unit causing M. And because the message reaches receiver. Receiver can decipher that message. as a result of once we area unit spoken language that nobody will perceive the message thus however can the receiver comprehend it that the receiver needs to decipher the message. decipher suggests that convert M' to M once more.

Meaning convert cipher text to plain text. thus sender will cryptography Receiver will

Decryption and once decrypting he can browse plain text. thus on the method the unauthorized user can suppose it's M' however it's M. thus cryptography isn't a brand new term. though it's turning into very fashionable. as a result of if we tend to remark network security If we tend to remark network security or cyber security in today's time. it's very fashionable. however it doesn't mean that cryptography is employed in today's time. Cryptography started at the time of Caesar. King of Rome was Caesar. He used a way known as Caesar’s cipher and thru it if he talked to a different king. in order that they wont to write the message in such the simplest way that nobody may write that message. however once assaultive the message carrier.

 Anyone may take the message. however it doesn't mean that they may browse the message they need to decipher to browse that message. And for decrypting we'd like a key and he wouldn't have that key. that's known as cryptography otherwise you will say cryptography. and the way will we reach confidentiality. Through cryptography methodology here we've got a crucial construct that we tend to use cryptography in 2 ways in which. parallel and uneven. parallel and uneven parallel suggests that of same key that means with the key used for cryptography. With constant key it'll decipher Like same, the lock that we tend to use reception with the key we tend to closed the lock. If I take my neighbors key and unlock its anyone will unlock it No.With the key wont to lock. And with some another key we will unlock. We will see about this in detail this is just the introduction of cryptography this is very important for UGC net and GATE exam.Because many questions are asked on cryptography in that. So that is the basic introduction. Then we will see symmetric and asymmetric key.