Cisco PIX Firewalls deliver a broad range of advanced firewall services that protect enterprise networks from the threats lurking on the Internet and in today's network environments. The state-of-the-art Cisco Adaptive Security Algorithm (ASA) provides rich stateful inspection firewall services, tracking the state of all authorized network communications and preventing unauthorized network access. Cisco PIX Firewalls deliver an additional layer of security through intelligent, "application-aware" security services that examine packet streams at Layers 4 through 7, using inspection engines specialized for many of today's popular applications. Administrators can easily create custom security policies that will be enforced on network traffic traversing the firewall by leveraging more than 100 pre-defined applications, services, and protocols within Cisco PIX Firewalls, and the flexible access control capabilities that Cisco PIX Firewalls provide. Access to network resources can also be strongly authenticated via the Cisco PIX Firewall's seamless integration with enterprise databases, either directly using TACACS+/RADIUS or indirectly via Cisco Secure Access Control Server (ACS). In addition to these services, Cisco PIX Firewalls provide extensive logging, URL filtering, content filtering, and more in concert with Cisco AVVID (Architecture for Voice, Video and Integrated Data) partner solutions.