There is an authentication and authorization for SignalR hubs example available here:
Authentication and Authorization for SignalR Hubs: http://www.asp.net/signalr/overview/security/hub-authorization
The article describes how to use various authentication options for .NET clients including Windows authentication, certificates and custom tokens.
But if you have any further questions related to SignalR, you should asked them at
http://forums.asp.net/1254.aspx/1?ASP+NET+SignalR and not here in the WPF forum.
Hope that helps.
Please remember to close your threads by marking helpful posts as answer and then start a new thread if you have a new question. Please don't ask several questions in the same thread.