why session id different in laravel 5.1 on reload?

I'm having a problem with session id in Laravel 5.1 (in 4.2 version is fine)

Every time I reload the page, Session::getId() returns a different value. So, whats wrong?

EDIT:

its some code in route.php:

print_r(\Session::getId()); // this show different value on reload page

via Chebli Mohamed