How Does Rsa Cryptography Work

Oxford Sedleian Professor of Natural Philosophy Jon Keating explains the RSA Cryptography Algorithm. Get 25% off Blinkist premium and enjoy 2 memberships for the price of 1! Start your 7-day free trial by clicking here https://www.blinkist.com/tomrocksmaths . . RSA encryption is used everyday to secure information online, but how does it work? And why is it referred to as a type of public key cryptography? Professor Jon Keating worked alongside the UK intelligence agency GCHQ for many years, and therefore knows a thing or two about encrypting secret messages. Here, he explains how the RSA algorithm works in general, and goes through 2 worked examples with small prime numbers. . . The algorithm relies on the idea that whilst it is very easy to multiply two prime numbers together, it is extremely difficult to break up a large number (with several hundred digits) back into its prime factors. Using some clever results from Number Theory – including Fermat’s Little Theorem and the Euler Totient Function – the message can be decrypted only if you know the original prime factors. This means advertising the product of the primes, or ‘public key’, enables people to send you a message without compromising the security of the encryption system. Even if the message is intercepted, it can only be decoded with knowledge of the prime factors – and these are incredibly difficult to obtain. . . This video is sponsored by Blinkist.. . Additional images and footage are used under a creative commons licence – links below.. . Blockchain Travel: https://www.youtube.com/watch?v=_Ui3s-Vp8_k . . Produced by Dr Tom Crawford at the University of Oxford. Tom is an Early-Career Teaching and Outreach Fellow at St Edmund Hall: https://www.seh.ox.ac.uk/people/tom-crawford . . For more maths content check out Tom’s website https://tomrocksmaths.com/ . . You can also follow Tom on Facebook, Twitter and Instagram @tomrocksmaths.. https://www.facebook.com/tomrocksmaths/ . https://twitter.com/tomrocksmaths . https://www.instagram.com/tomrocksmaths/ . . Get your Tom Rocks Maths merchandise here:. https://beautifulequations.net/collections/tom-rocks-maths