title: Is System.Security.Cryptography namespace supported by the Portable Class Library
body: <p>I am converting an existing multi-target Silverlight/.NET project to a Portable Class Library project in order to reduce the number of projects that are required to support multiple Microsoft platforms.</p>
  
  <p>I have an error in one class that is using the System.Security.Cryptography namespace </p>
  
  <blockquote>
    <p>The type or namespace name 'Cryptography' does not exist in the namespace 'System.Security' (are you missing an assembly reference?)</p>
  </blockquote>
  
  <p>This namespace is available in Silverlight and I am wondering why the Portable Class Library does not support it?</p>
  
  <p>One reason could be that this behaviour is by design: any cryptography related code should not be present in a client side API.</p>