How many firewalls are typically required to set up a sandwich DMZ?

To establish a sandwich DMZ, two firewalls are typically required. The sandwich DMZ architecture leverages a configuration where the DMZ is situated between two firewalls.

The primary purpose of this setup is to enhance security by creating multiple layers of defense. The outer firewall acts as the first line of defense, controlling incoming and outgoing traffic to and from the external network (such as the internet). The inner firewall protects the internal network by controlling traffic between the DMZ and the private network.

By having two firewalls, the configuration ensures that even if one firewall is compromised, the other can still provide a barrier to protect critical internal resources. This arrangement significantly reduces the risk of unauthorized access and enhances the overall security posture of the network.

Using only one firewall would not provide a sandwich configuration and would not achieve the layered security benefits that come with a two-firewall solution. Therefore, two firewalls are essential for setting up a sandwich DMZ effectively.