title: Two-phase commit vs Paxos
body: <p>I am quite confused with these two technologies.</p>
  
  <ol>
  <li><p>Are there any relationship between these two technologies</p></li>
  <li><p>Are there any existing popular open source software implements these technologies? I know zookeeper implements Paxos but what about Two-phase commit?</p></li>
  </ol>