title: Confused about protobuf-net WCF usage
body: <p>I have been following <a href="http://blog.marcgravell.com/2009/11/controlling-wcf-protobuf-net-at.html" rel="nofollow noreferrer">this tutorial</a> to add <code>protobuf-net</code> to my WCF project. I have a shared DTO library. Both server and Client use those DTO classes. I have attributed all my Service methods with <code>[OperationContract]</code> attributes, but i have not assigned any <code>[DataContract]</code> attributes on my DTO classes.</p>
  
  <p>I added the <code>protobuf-net</code> Nuget package and added the configuration to the <code>web.config</code>.</p>
  
  <p>I am using IIS Express to test my service, and thought that i should be ok with what i had done so far. However, after testing a few calls, i noticed that i forgot to add <code>protobuf-net</code> to my client and yet everything worked as expected (ie. no errors from serialization or deserialization). </p>
  
  <p>I suspect that protobuf is not used in my program at all, and that i am missing something. <a href="https://stackoverflow.com/questions/5921635/is-datacontract-attributes-required-for-wcf">I'd like to avoid using <code>[DataContract]</code> attributes</a> but i could live with adding them, if that is what is need to get <code>protobuf-net</code> working.</p>
  
  <p>What else am i missing? </p>