When I found the Shields Up! website last week, I wondered which of the more popular firewall software is actually more secure than the rest. This curiosity led to this article. By now, it is clear who the winner is. While the concept of shielding a PC is the same, ZoneLabs has been able to put this concept to use in the most elegant way. While the free version of ZoneAlarm is sufficient for home use, professionals and business users find the more aggressive protection of ZoneAlarm pro more appealing.