Cisco FirePOWER ASA 5500 series User Manual

15-12
Cisco Security Appliance Command Line Configuration Guide
OL-10088-01
Chapter 15 Firewall Mode Overview
Transparent Mode Overview
This section describes how data moves through the security appliance, and includes the following topics:
• An Inside User Visits a Web Server, page 15-12
• An Outside User Visits a Web Server on the Inside Network, page 15-13
• An Outside User Attempts to Access an Inside Host, page 15-14
An Inside User Visits a Web Server
Figure 15-9 shows an inside user accessing an outside web server.
Figure 15-9 Inside to Outside
The following steps describe how data moves through the security appliance (see Figure 15-9):
1. The user on the inside network requests a web page from www.example.com.
2. The security appliance receives the packet and adds the source MAC address to the MAC address
table, if required. Because it is a new session, it verifies that the packet is allowed according to the
terms of the security policy (access lists, filters, AAA).
For multiple context mode, the security appliance first classifies the packet according to a unique
interface.
3. The security appliance and records that a session is established.
4. If the destination MAC address is in its table, the security appliance forwards the packet out of the
outside interface. The destination MAC address is that of the upstream router, 209.186.201.2.
If the destination MAC address is not in the security appliance table, the security appliance attempts
to discover the MAC address by sending an ARP request and a ping. The first packet is dropped.
Management IP
209.165.201.6
www.example.com
209.165.201.2
Host
209.165.201.3
Internet
92408

Cisco FirePOWER ASA 5500 series Specifications

General

Brand	Cisco
Model	FirePOWER ASA 5500 series
Category	Firewall
Language	English