.. _sphx_glr_api_gallery_crypto_one_time_pad:

One-time pad
------------

Vernam's cipher and Shannon's proof of perfect secrecy.


.. raw:: html

  <div id='sg-tag-list' class='sphx-glr-tag-list'></div>


.. raw:: html

    <div class="sphx-glr-thumbnails">

.. thumbnail-parent-div-open

.. raw:: html

    <div class="sphx-glr-thumbcontainer" tooltip="Vernam&#x27;s teleprinter cipher added a key tape to the message, character by character. Shannon later proved that if the key is truly random, as long as the message, and used once, the ciphertext reveals nothing: every plaintext of that length is equally consistent with it.">

.. only:: html

  .. image:: /api/gallery/crypto/one_time_pad/images/thumb/sphx_glr_plot_01_one_time_pad_thumb.png
    :alt:

  :doc:`/api/gallery/crypto/one_time_pad/plot_01_one_time_pad`

.. raw:: html

      <div class="sphx-glr-thumbnail-title">The one-time pad and perfect secrecy (Vernam 1917, Shannon 1949)</div>
    </div>


.. thumbnail-parent-div-close

.. raw:: html

    </div>


.. toctree::
   :hidden:

   /api/gallery/crypto/one_time_pad/plot_01_one_time_pad