using System.ServiceModel;

namespace SimpleService
{
	[ServiceContract]
	public interface ISimpleService
	{
		[OperationContract]
		string Method();
	}
}

using System.ServiceModel;

namespace SimpleService.Host
{
	class SimpleServiceImpl : ISimpleService
	{
		public string Method()
		{
			return OperationContext.Current.ServiceSecurityContext.PrimaryIdentity.Name;
		}
	}
}

using System;
using System.ServiceModel;

namespace SimpleService.Host
{
	class Program
	{
		static void Main(string[] args)
		{
			using (var host = new ServiceHost(typeof (SimpleServiceImpl)))
			{
				var binding = new WSHttpBinding();
				binding.Security.Mode = SecurityMode.Message;
				binding.Security.Message.ClientCredentialType = MessageCredentialType.Windows;

				host.AddServiceEndpoint(typeof(ISimpleService), binding, 
					"http://localhost/Temporary_Listen_Addresses/SimpleService");

				host.Open();
				Console.WriteLine("Service started");
				Console.ReadLine();
				host.Close();
			}
		}
	}
}

using System;
using System.ServiceModel;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace SimpleService.Client
{
	[TestClass]
	public class AuthenticationSample
	{
		WSHttpBinding binding = new WSHttpBinding
			{
				Security =
				{
					Mode = SecurityMode.Message,
					Message = { ClientCredentialType = MessageCredentialType.Windows }
				}
			};

		[TestMethod]
		public void CurrentUserAithentication()
		{
			var factory = new ChannelFactory<ISimpleService>(binding,
				"http://localhost/Temporary_Listen_Addresses/SimpleService");

			var client = factory.CreateChannel();
			Console.WriteLine(client.Method());
		}

		[TestMethod]
		public void DifferentUserAithentication()
		{
			var factory = new ChannelFactory<ISimpleService>(binding,
				"http://localhost/Temporary_Listen_Addresses/SimpleService");
			factory.Credentials.Windows.ClientCredential =
				new System.Net.NetworkCredential("TestUser", "123");

			var client = factory.CreateChannel();
			Console.WriteLine(client.Method());
		}
	}
}