title: Difference between IP address and MAC address?
body: <p>I know they are address schemes used in different layers, and that IPV4 is 32 bits while MAC is 48 bits.</p>
  
  <p>My questions are:</p>
  
  <ul>
  <li><p>Why do we need two different address schemes?</p></li>
  <li><p>What is the problem if we decided to use the same address for both purposes? </p></li>
  <li><p>Is there a reason for the MAC address requiring more memory? </p></li>
  <li><p>Has the introduction of ipv6 changed anything?</p></li>
  </ul>