public class Service1 : IService1
    {
        public void DoWork()
        {
            Thread.Sleep( 5000 );
            OperationContext.Current.GetCallbackChannel<ICallback>().Notify("Notify");
        }
    }

            var httpAddress = new Uri("http://localhost/Service1.svc");
            ServiceHost host2 = new ServiceHost(typeof(Service1), httpAddress);
            WSDualHttpBinding wsDualHttpBinding = new WSDualHttpBinding();
            wsDualHttpBinding.TransactionFlow = true;
            wsDualHttpBinding.SendTimeout = new TimeSpan( 0 ,  4 ,  0 ,  0 );
            wsDualHttpBinding.ReceiveTimeout = new TimeSpan( 0 ,  4 ,  0 ,  0 );
            wsDualHttpBinding.OpenTimeout = new TimeSpan( 0 ,  0 ,  10 ,  0 );
            wsDualHttpBinding.CloseTimeout = new TimeSpan( 0 ,  0 ,  10 ,  0 );
            wsDualHttpBinding.Security.Mode = WSDualHttpSecurityMode.None;
            wsDualHttpBinding.Security.Message.ClientCredentialType = MessageCredentialType.None;
            wsDualHttpBinding.MaxReceivedMessageSize =  2147483647 ;
            wsDualHttpBinding.MaxBufferPoolSize =  0 ;
            wsDualHttpBinding.ReaderQuotas.MaxStringContentLength = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxArrayLength = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxBytesPerRead = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxDepth =  32 ;
            wsDualHttpBinding.ReaderQuotas.MaxNameTableCharCount =  16384 ;
            host2.AddServiceEndpoint(typeof(IService1), wsDualHttpBinding, "");

            var bindingElement = new WSHttpBinding();
            var metadataBinding = new CustomBinding(bindingElement);

            host2.Description.Behaviors.Add(new System.ServiceModel.Description.ServiceMetadataBehavior());
            host2.AddServiceEndpoint(typeof(IMetadataExchange), metadataBinding, "MEX");

            host2.Open();

            Console.WriteLine("Press enter to exit");
            Console.ReadLine();

            WSDualHttpBinding wsDualHttpBinding = new WSDualHttpBinding();
            wsDualHttpBinding.TransactionFlow = true;
            wsDualHttpBinding.SendTimeout = new TimeSpan( 0 ,  4 ,  0 ,  0 );
            wsDualHttpBinding.ReceiveTimeout = new TimeSpan( 0 ,  4 ,  0 ,  0 );
            wsDualHttpBinding.OpenTimeout = new TimeSpan( 0 ,  0 ,  1 ,  0 );
            wsDualHttpBinding.CloseTimeout = new TimeSpan( 0 ,  0 ,  10 ,  0 );
            wsDualHttpBinding.Security.Mode = WSDualHttpSecurityMode.None;
            wsDualHttpBinding.Security.Message.ClientCredentialType = MessageCredentialType.None;
            wsDualHttpBinding.MaxReceivedMessageSize =  2147483647 ;
            wsDualHttpBinding.MaxBufferPoolSize =  0 ;
            wsDualHttpBinding.ReaderQuotas.MaxStringContentLength = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxArrayLength = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxBytesPerRead = int.MaxValue;
            wsDualHttpBinding.ReaderQuotas.MaxDepth =  32 ;
            wsDualHttpBinding.ReaderQuotas.MaxNameTableCharCount =  16384 ;

            InstanceContext ic = new InstanceContext(new Callback());
            DuplexChannelFactory<IService1> f = new DuplexChannelFactory<IService1>(ic, wsDualHttpBinding, new EndpointAddress("http://ticserv04/Service1.svc"));
            var s = f.CreateChannel();
            s.DoWork();