Although IPSs are a promising addition to the arsenal of security products, they are relatively new and, therefore, not without problems, As mentioned earlier, deep packet inspection slows overall throughput. In addition, IPSs are prone to false alarms, which results in rejecting legitimate traffic. Nevertheless, a great deal of research is being undertaken to improve the intelligence of IPSs and they are likely to become an important part of an organization’s security toolkit. IPSs will not, however. Replace the need for firewalls. Instead, they are a complementary tool and provide yet another layer of perimeter defense.