using System;
using System.Security;
using System.Security.Permissions;
using System.Security.Cryptography.X509Certificates;

public class Dog
{
	public void Barking()
	{
		try
		{
			X509Certificate cert=X509Certificate.CreateFromCertFile("sample.cer");
			PublisherIdentityPermission pidentity=
				new PublisherIdentityPermission(cert);
			pidentity.Demand();
			Console.WriteLine("Dog barking...");
		}
		catch(SecurityException)
		{
			Console.WriteLine("This dog does not bark");
		}
	}
}