The Unbreakable Cipher: One-Time Pads (2 of 2: Their Weaknesses)

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  • Опубліковано 30 жов 2014

КОМЕНТАРІ • 38

  • @KiwiBeeArt
    @KiwiBeeArt 7 років тому +59

    I wish all teachers were as enthusiastic about teaching as you are.

    • @torswq2637
      @torswq2637 4 роки тому

      He is really cool and good as a professor, you just need to listen and do not talk from the ignorance, cause you made other students answers, opaque or make everyone lose time, the example of what i am saying is when Eddie ask a student to explain Authentication/Integrity, literally, there are no auth methods for this, it is all about respecting the index and the secrecy of the OTP

  • @miaminyze
    @miaminyze 9 років тому +28

    You Sir are a genuis! That has been the best crypto explanation ever!

    • @michael-gary-scott
      @michael-gary-scott 8 років тому +1

      ikr! This guy is soo good!

    • @a2cg2ogle
      @a2cg2ogle 7 років тому

      i dont know who the audience is but that they even think about the problem of punctuation shows that neither he nor the students know how cryptography gets used in out world (https, ssh, etc.)
      if this is a lecture for non software developers (for example some random BA people) it is probably fine.

  • @GoldenWingsLittleBirds
    @GoldenWingsLittleBirds 4 місяці тому

    I love maths. These videos inspire me to love maths more!

  • @marksilen2652
    @marksilen2652 4 роки тому +3

    What a fantastic teacher.........you rock !!!

  • @nasriza7424
    @nasriza7424 3 роки тому +1

    I straight watch part 2 after watching part 1. Really interesting way of teaching. Thanks!

  • @thescarzy
    @thescarzy 9 років тому +7

    Great Eddie! Energetic, enthusiastic ,and engaging even from UA-cam. I wish my maths tutors were like you!
    The authentication point that was made and discarded is a valid one. OTP requires no authentication, just an exchange of keys (OTP). Therefore, Mike could be impersonating Eddie using Eddie's distributed OTP, and Brendan would not know. This is another limitation.

  • @MuhammadMuhaddis
    @MuhammadMuhaddis 3 роки тому +5

    The best teacher I never had in my college

    • @pldoolittle
      @pldoolittle 3 роки тому

      I had a teacher like him. Iason Rusodimos in the Mathematics department at Georgia State University Perimeter College. Fantastic guy.

  • @djjones11
    @djjones11 5 років тому +3

    Great teaching style, thanks

  • @Chris_Hetherington
    @Chris_Hetherington 4 роки тому +3

    The agents would be sent into where ever they were going with a book of pads. The first 5 digits of the encrypted message would be the first 5 digits of the key, that is how you know you are using the same key. As for the randomness, 2 dice were used to generate truly random numbers.

    • @wiktorwektor123
      @wiktorwektor123 4 роки тому +1

      I'm sorry but 2 dice can't generate TRUE random numbers. No number of dices can. Imperfection in manufacturing will favor some numbers more than others.
      ua-cam.com/video/9rIy0xY99a0/v-deo.html (I've recommend watchig all not just from place I put link to)

    • @Chris_Hetherington
      @Chris_Hetherington 4 роки тому +1

      @@wiktorwektor123 even if there are imperfections, and a computer were to figure it out, by that time the message will no longer be relevant.

  • @ladmerc
    @ladmerc 8 років тому +3

    It stopped when the fun began

  • @shrinathbhoslay3014
    @shrinathbhoslay3014 5 років тому +1

    Wish my math teachers were like him

  • @cl9826
    @cl9826 6 років тому +1

    In practice the numbers were printed in groups of 5. The first 5 numbers of the message were not enciphered but were just taken from the OTP as a Key ID so the receiver could verify they were using the correct page of the pad. A new page was used for each message. The codes were typically broadcast on short wave radio and sounded creepy as hell.

    • @jackbogrand4064
      @jackbogrand4064 3 роки тому

      ASA All the Way. 054.2 - Phubai 1963-1964 Ubon 1964-1965

  • @kelinmiao6080
    @kelinmiao6080 4 роки тому

    Another minor weakness, is that if a message did not make it, then one persons decryption would be out of order by at least one page, requiring the next page be used, it can still work after a missed message but its another thing to remember to do when you get a giberish message

  • @kalxite
    @kalxite 5 років тому

    why i never had a teacher like this

  • @KempSanders
    @KempSanders 2 роки тому

    If you lost a page you would look at the remaining page, and figure out how many characters to count forward to continue with decryption. Trial and error if there’s not a uniform number on each page.

  • @jeffreyweaver9854
    @jeffreyweaver9854 2 роки тому

    I'm sorry! I thought that this would involve creating random groups of letters for the key and combining them with the Vigenere grid!

  • @badhbhchadh
    @badhbhchadh 5 років тому +4

    7:16 Has to be 3.141592653

  • @Mortico88
    @Mortico88 Рік тому

    Using wartime communications as a backdrop, if someone breaches the headquarters that is sending messages out, they can then send false or confusing orders. There is no way for the receiving party to know the message was sent from the expected person. I'm sure there's a solution for this, but what it it?

  • @andrewpersaud4144
    @andrewpersaud4144 5 років тому +1

    minus 5 billion points for you. the student who said integrity was spot on and you dismissed him. If someone intercepts the ciphertext and has an idea what a part of the plain text is, they can easily change the ciphertext so that when decrypted it means something totally different. For instance if someone sends a message to someone to buy stocks, and the hacker has an idea of what the buy looks like, he can change the buy to sell without even having the key.

  • @challengepoker
    @challengepoker 9 років тому +2

    Where's the end of the video ??

  • @flamephlegm
    @flamephlegm 5 років тому +1

    where is the rest of this?

  • @farsyoussef1765
    @farsyoussef1765 7 років тому +2

    Exchange problem can be solved using "Diffie-Hellman"

    • @badhbhchadh
      @badhbhchadh 5 років тому

      Or RSA.

    • @steveberglund3933
      @steveberglund3933 4 роки тому +2

      Totally not true. Using any key exchange algorithm that is less secure causes the OTP to become as weak as DH or RSA. The point of the OTP is to be unbreakable infinitely into the future as long as the key is not compromised. Once you use DH or RSA or any other method of key exchange, you lose the benefits of OTP and therefore you may as well use an existing public key cryptosystem.

  • @travelright8150
    @travelright8150 5 років тому

    Entanglement theory crypto