Firewall Deployment for Device Visibility
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Focus
IoT Security

Firewall Deployment for Device Visibility

Table of Contents

Firewall Deployment for Device Visibility

Deploy your firewall so it can log network traffic data for DHCP flows and forward the logs to Strata Logging Service.
Where Can I Use This?What Do I Need?
  • NGFW (Managed by PAN-OS or Panorama)
  • IoT Security subscription for an advanced IoT Security product (Enterprise Plus, Industrial OT, or Medical)
The Palo Alto Networks IoT Security app uses machine learning to classify IoT devices based on the network traffic for which these devices are either a source or destination. To accomplish this, it relies on Enhanced Application logs (EALs) generated by the Palo Alto Networks Next-Generation Firewall.
DHCP traffic is of particular importance to the IoT Security solution. DHCP provides a way to create an IP address-to-device mapping (that is, an IP address-to-MAC address mapping) that is required for classification to take place. However, a firewall typically only generates an EAL entry when it receives a unicast DHCP message; for example, when there is centralized Internet Protocol address management (IPAM) and either the firewall or another local device acts as a DHCP relay agent. Below is an example architecture that illustrates a common case where the firewall generates EALs for unicast DHCP traffic.
The firewall generates an EAL entry for broadcast DHCP traffic when the packet is seen on a virtual wire (vWire) interface with multicast firewalling enabled, as shown below.

DHCP Data Collection by Traffic Type

Enhanced Application log (EAL) coverage differs when the firewall receives unicast and broadcast DHCP traffic.
The tables below show Enhanced Application log (EAL) coverage when the firewall interface receiving unicast and broadcast DHCP traffic is in different modes.
Unicast DHCP Traffic
Firewall Interface Deployment ModeDHCP EAL Generated
Virtual WireYes
TapYes
Layer 2Yes
Layer 3Yes
Broadcast DHCP Traffic
Firewall Interface Deployment ModeDHCP EAL Generated
Virtual WireYes
TapNo
Layer 2No
Layer 3No
DHCP server on the firewall (L3, L2 with VLAN interface) Yes*
DHCP relay agent on the firewall (L3, L2 with VLAN interface) Yes
A firewall running a PAN-OS 10.0 release or later natively generates EALs when a DHCP server is configured on an interface, DHCP Broadcast Session is enabled, and there’s a Security policy rule that allows DHCP traffic to reach the server and has EAL forwarding enabled. For more information, see Prepare Your Firewall for IoT Security and Configure Policies for Log Forwarding.