title: Using SAM modules for storing secure keys
body: <p>As i understand SAM modules are kind of SMART Cards which connect to the MCU via ISO 7816 protocol.</p>
  
  <ol>
  <li>Is there any other application for them except storing secure
  keys?</li>
  <li>Can I used usual mobile sim-cards instead of SAM module to storing
  keys?</li>
  <li>As i know when we store keys in the SAM module ,it is almost
  impossible to retrieve the keys, &amp; SAM used a sequence of random
  challenge &amp; polyphase authentication to verify the card.Then how SAM
  send this verification to MCU?is there direct access between SAM &amp;
  Reader ? or they connected via MCU?which command used to store keys
  in the SAM?</li>
  <li>Is there any special standard protocol for this secure
  transmission? (storing key in SAM/ Authentication between
  CARD-SAM-MCU/ verifying process &amp; ...)</li>
  <li>Why chip manufacturer does not equipped their MCU to this secure
  Element internally?</li>
  </ol>