using System;

public class Program

{

    public static void Main()

    {

        var plainTextBytes = System.Text.Encoding.UTF8.GetBytes("127.0.0.1");

        var temp1 = System.Convert.ToBase64String(plainTextBytes);

        Console.WriteLine(temp1);

        var base64EncodedBytes = System.Convert.FromBase64String(temp1);

        Console.WriteLine(System.Text.Encoding.UTF8.GetString(base64EncodedBytes));

    }

}