History of cryptography
b'hello everyone my name is vijay kumar devireddy and i am glad to have you back on my episode 04 well we had\\ndiscussed about cryptography and how it helps us to protect the information in the internet world in this\\xa0\\nepisode we are going to discuss about how it had evolved . for that\\xa0\\nwe will jump into the history to know it briefly .\\n\\nSending secret messages has been a documented human activity for thousands of years. The earliest example I\\xa0\\nam aware of can be found in the bible, from approximately 2600 years ago. it was named as The AT BASH cipher\\xa0\\nwhich we call it as substitution ciper now in this Encryption works by substituting each letter in the alphabet\\xa0\\nby another letter.\\n\\nCaesar\\u2019s Cipher\\nAnother substitution cipher from the ancient world is \\u201cCaesar\\u2019s Cipher\\u201d, named after Julius Caesar who used\\xa0\\nit in his private correspondence, about 500 years after ATBASH cipher. To encrypt a message with\\xa0\\nCaesar\\u2019s cipher, each letter is replaced by a letter 3 places earlier in the alphabet: \\u201cshifting back by 3\\u201d\\xa0\\n- so D becomes A, E becomes B, and wrapping around so A becomes X.\\n\\n\\nFor many centuries cryptography was used quite extensively - as a \\u201cdark art\\u201d, employed by royals, diplomats,\\xa0\\nspies, and the military. It played an important role in many historical events. Probably the most famous in\\n\\xa0modern history is the story of the Enigma cipher used by the Germans in World War 2, and the allied forces\\u2019\\n\\xa0success in breaking that cipher.\\n\\xa0\\nThis all changed in the 1970s. By then important and sensitive electronic communication systems emerged in the\\n\\xa0civilian market - most notably \\u201cAutomatic Teller Machines\\u201d (ATMs) allowing cash withdrawals. Motivated by the\\xa0\\nneed to protect civilian communications from criminals, the US standards body (which is now called NIST),\\xa0\\nrealized that a cipher is needed to protect sensitive (but non-classified) information.\\xa0\\n\\nThe result was the design, and public standardization, of the first civilian cipher, called the Data Encryption\\n\\xa0Standard (DES). DES was designed by IBM in the 1970s and became a US federal standard in 1977.\\nand des was used for 30 years and later found it as vulnerable to protect the sensitive information with the\\xa0\\nmodern technologies we will discuss this later'