Chapter 2 Deploying Your Device
This chapter introduces how a firewall works and its most commonly used scenarios. Understanding the system structure, basic elements and flow chart will help you in better organizing your network and making the most of the firewall product.
A firewall has more than one deployment scenario. Each scenario applies to one environment requirement. The usual deployment modes are:
- Deploying Transparent Mode
Transparent mode is a situation when the IT administrator does not wish to change his/her existing network settings. In transparent mode, the firewall is invisible to the network. Because no IP address configuration is needed, the firewall only provides security features.
- Deploying Routing Mode
Routing mode applies when the firewall offers both routing and NAT functions. In routing mode, the firewall connects two networks typically, an internal network and the Internet, and the firewall interfaces are configured with IP addresses.
- Deploying Mix Mode
If a firewall has Layer-2 interfaces and Layer-3 interfaces, it is in mix mode.
- Deploying Tap Mode
When an IT administrator only wants the monitor, IPS or statistic function of a firewall, while not a gateway device, using tap mode is the right choice. In tap mode, the firewall is not directly connected within the network.