org.openqa.selenium.SessionNotCreatedException: Unable to create new remote session

Question

I am trying to setup selenium grid. and follow the following steps:-

1) Start hub on Windows 10 (32 bit) :- java -jar "path to standalone jar" -role hub -port 4444

2) Start node on Ubuntu14.04 (64 bit) :- java -jar "path to standalone jar" -role webdriver -port 5555 -hub "http:// ip of windows PC:4444/grid/hub"

The node and hub started successfully. But the problem is when I am trying to execute the following script it throws exception " org.openqa.selenium.SessionNotCreatedException: Unable to create new remote session" Please look at the following code:-

public class gridclass
{
    public static void main(String[] args)
  {
    System.setProperty("webdriver.gecko.driver","Path to/geckodriver");
    WebDriver wd=null;
    try
    {   
        DesiredCapabilities desire = DesiredCapabilities.firefox();
        wd = new RemoteWebDriver( new URL("http://path to hub URL/grid/hub"), desire);
    } 
    catch (MalformedURLException e)
    {
        e.printStackTrace();
    }
    wd.get("http://www.google.com");
    wd.close();
    wd.quit();
 }
}

The above code I have written on Windows 10 (i.e on hub machine). Is that the correct way?

If it the correct and code is correct then how to solve org.openqa.selenium.SessionNotCreatedException. Please help me in this case.