$ssh2= Net::SSH2->new();

	my $host = 'serveraddress';
	my $port = 22;
	my $user = 'username';

	$ssh2->connect($host, $port) or $ssh2->die_with_error;

	my $ppk_filepath = 'C:\Users\username\rsa-key-username';

	print "$ppk_filepath exists!\n" if -e $ppk_filepath;

	$ssh2->auth_publickey($user, undef, $ppk_filepath, 'passphrase123' ) or $ssh2->die_with_error;