FortiGate Zone

Zones are a group of one or more physical or virtual FortiGate interfaces that you can apply firewall policies to for controlling inbound and outbound traffic. Grouping interfaces and VLAN subinterfaces into zones simplifies creating firewall policies where a number of network segments can use the same policy settings and protection profiles.

In firewall terminology, an "interface zone" refers to a grouping of interfaces based on their security profiles and trust levels. Interface zones play a crucial role in defining security policies and controlling traffic flow between different parts of the network. Here's a closer look at interface zones:

• Definition: An interface zone is a logical construct that categorizes interfaces based on their security requirements and the level of trust associated with the traffic passing through them. Each interface is assigned to a specific zone, which helps determine how traffic is allowed or denied between interfaces within the same zone and across different zones.

• Purpose: Interface zones provide a simplified way to manage security policies by grouping interfaces with similar security requirements together. For example, interfaces belonging to the internal network (LAN) might be grouped into a "trusted" zone, while interfaces connecting to the Internet (WAN) or hosting publicly accessible services might be categorized into a "untrusted" or "DMZ" zone.

• Security Policies: Firewall administrators define security policies that govern traffic between interfaces belonging to different zones. These policies specify which types of traffic are allowed, denied, or subjected to further inspection based on criteria such as source/destination IP addresses, ports, protocols, and application types. For example, traffic from the trusted zone to the untrusted zone might be allowed for web browsing but blocked for certain sensitive services.

• Traffic Control: Interface zones facilitate granular control over traffic flow within the network. Traffic between interfaces within the same zone (intra-zone traffic) may have less restrictive policies compared to traffic between interfaces in different zones (inter-zone traffic), reflecting the varying levels of trust between different parts of the network.

• Examples of Interface Zones:

  • Trusted Zone: Contains interfaces representing the internal LAN, where organizational resources and sensitive data are located.

  • Untrusted Zone: Includes interfaces connecting to the external network, such as the Internet, where potential threats originate.

  • DMZ (Demilitarized Zone): Hosts publicly accessible servers, such as web servers, email servers, or FTP servers, and acts as a buffer between the trusted and untrusted zones.

  • VPN Zone: Comprises interfaces used for VPN connections, allowing remote users or branch offices to securely access the internal network.

• Configuration and Management: Firewall administrators configure interface zones and associated security policies according to the organization's security policies and network architecture. They ensure that traffic between zones is appropriately controlled to mitigate security risks and comply with regulatory requirements.

In summary, interface zones in firewalls provide a structured approach to managing network security by grouping interfaces with similar security profiles together and defining policies to control traffic between them. This helps organizations enforce access control, protect sensitive data, and mitigate security threats effectively.