title: RNGCryptoServiceProvider in .Net Core
body: <p>I cannot find the System.Security.Cryptography.RNGCryptoServiceProvider class in .NetCore.</p>
  
  <p>It is essential to the application I am trying to port from .Net Framework, as it is being used to generate an initialisation vector for encryption.</p>
  
  <p>Does it exist under a different name, or is there another way of achieving this functionality?</p>