Summary

Firewalls provide a wide variety of capabilities to administrators. From simple packet filtering to deep packet inspection, modern firewalls enable administrators to significantly improve the security of their network. Many of the previously "high-end" capabilities such as stateful packet inspection have been slowly making their way into the lower-end firewalls, such as the Linksys BEFSX41 and the PIX 501. Additionally, these higher-end capabilities have been making their way into the open source firewall codes, a fact that allows all administrators to secure their systems at very low cost.