| 8.2 |  | The Cisco PIX Security Appliance |
| 8.2.1 |  | Introduction to the PIX Security Appliance |

| The PIX Security Appliance is a dedicated hardware and software security solution that delivers high-level security without impacting network performance. It is a hybrid system because it features packet filtering, proxy server, VPN, and intrusion detection technologies.

The PIX Security Appliance is a closed system by default. The default PIX Security Appliance settings allow all connections from the inside interface access to the outside interface, and they block all connections from the outside interface to the inside interface.

PIX Security Appliance features
The PIX Security Appliance features the following technologies and benefits:

- Finesse OS - Finesse is a non-UNIX, secure, real-time, embedded system. Unlike typical CPU-intensive proxy servers that perform extensive processing on each data packet at the application layer, the PIX Security Appliance uses a secure, real-time, embedded system, which enhances the security of the network.
- Adaptive Security Algorithm (ASA) - Implements stateful connection control through the PIX Security Appliance.
- Cut-through proxy - A user-based authentication method of both inbound and outbound connections that provides improved performance in comparison to that of a proxy server.
- Stateful packet filtering - A secure method of analyzing data packets that places extensive information about a data packet into a table. For a session to be established, information about the connection must match the information in the table.

Additional features and capabilities of the PIX are shown in Figure . There are several methods to access the PIX .