DistributedTransactionPermissionAttribute
Allows security actions for  DistributedTransactionPermission to be applied to code using declarative security. This class cannot be inherited.
                using System.Security;
using System.Security.Permissions;
namespace System.Transactions
{
    [AttributeUsage(AttributeTargets.All, AllowMultiple = true)]
    public sealed class DistributedTransactionPermissionAttribute : CodeAccessSecurityAttribute
    {
        public new bool Unrestricted { get; set; }
        public DistributedTransactionPermissionAttribute(SecurityAction action)
            : base(action)
        {
        }
        public override IPermission CreatePermission()
        {
            return null;
        }
    }
}