Symmetric Key Cryptography: The Rail Fence Cipher

This is the third in a series about cryptography; an extremely important aspect of computer science and cyber security. It covers a transposition cipher called the rail fence cipher, also known as the zig zag cipher. It explains how this method can be used to scramble the letters in a plain text message to generate cipher text. It also explains how the rail fence cipher can be used with different keys. The video includes a examples you can try to encrypt and decrypt yourself.

[@DJAlax909]

Thank you for making an explanation thats short and straight forward.

[@absalomherreraramirez4847]

Your videos are so good. Hope to see something on operating systems soon.

[@muhammedsami3058]

Thank you so much Kevin ! So helpfull.

[@fataz5728]

This was soo useful. I have competition tmrw at school and these are needed. I didntunderstand a thing in the other videos but your video is so clear

[@ComputerScienceLessons]

Glad to help. I hope it went well. :)KD

[@Kurd.zanyari]

Thank you 🙏

[@leooel4650]

Cheers, the first 1.27 mins were more than enough for me, to implement in Python :)

[@smit17xp]

kool profile pic

[@_ILunar]

Hey sir, why in the example at the end of the video the key is 4, do we need to try or is there any way to know that?

[@billchen4923]

Please receive my admiral. I really enjoy watching your teaching video.

[@ComputerScienceLessons]

Thank you :)KD

[@Sigmarequintista]

How do you do this with an offset, on my science olympiad test this method didn't work because there was an unknown offset

[@harsinsinquin4032]

How to improve the cipher: fill in the blanks of the grid to make real sentences even if they come out nonsensical.

[@variblex]

thanks studying crypto and this was quick easy and ...going to be fun to send quick easy messages with friends

[@ComputerScienceLessons]

Glad to help :)KD

[@tryxxsi2275]

Thank you so much that help me a lot ❤

[@ComputerScienceLessons]

You're welcome :)KD

[@kestergideon5359]

With the final example how did u know what the encryption key was ? Is it always based on trial Nd error or is there a way to find it

[@ComputerScienceLessons]

Use a 'brute force' approach (trial and error). In fact, it's an easy one to crack with this approach, so it is normally used in conjunction with other ciphers.

[@lindawalker8998]

With the puzzle Fine words butter no parsnips. I did draw 25 blocks but how do you know it was 4? How do you find that out?

[@ComputerScienceLessons]

Use a 'brute force' approach (trial and error). In fact, it's an easy one to crack with this approach, so it is normally used in conjunction with other ciphers.

[@LucyFur.]

Key 2:
cool = cool

[@ComputerScienceLessons]

:)KD

[@venkatasaisandhyaivaturi2033]

thank you o much sir

[@ComputerScienceLessons]

You're very welcome :)KD

[@smit17xp]

Thanks sir

[@ComputerScienceLessons]

You're welcome :)KD

[@manav9518]

Remember guys your key should not be more than total letters in you sentence or it'll end up in original sentence without any encryption

[@ComputerScienceLessons]

Good point :)KD

[@webskhristi8705]

someone from uk is speaker

[@yigite7034]

Türkçe yok 1 yıldız

[@ComputerScienceLessons]

? :)KD

[@yigite7034]

@@ComputerScienceLessons I am just messing around ^^ Keep up the good work