Using ntopng with nProbe IPS

ntopng can be used to enforce traffic policies and report them, when ntopng is used in combination with nProbe in IPS mode.


A ntopng Pro or Enterprise license is required.

Traffic policies are automatically exported to nProbe after a change to the policies configuration, or when a new nProbe instance connects to ntopng via ZMQ. In order to publish IPS events (including policies) an additional ZMQ channel is required. This can be configured using the --zmq-publish-events option to configure the ntopng ZMQ endpoint for IPS events. Example:

nprobe --zmq tcp://*:1234 --ips-mode none --zmq-publish-events tcp:// -i nf:0
ntopng -i tcp:// --zmq-publish-events tcp://*:5557

Please refer to the nProbe documentation for more details about the nProbe configuration and working mode.

A different traffic policy can be configured for each pool of hosts (see Host Pools) by clicking on the “key” button in the Pools > Host Pool Members page, after selecting the System interface.

Edit Host Pool Policy

The Host Pool Page

The policies configuration includes a default policy, that can be Pass or Drop (Default Deny), and more specific rules that can be used to configure exceptions with respect to the default policy, including:

  • L7 Application Protocol Rules
  • L7 Category Rules
  • Host Rules to configure hostnames used in TLS and DNS protocols for instance
  • Country Rules
  • Continent Rules
  • Risk Rules to apply policies based on the Flow Risk computed by nDPI
Edit Traffic Policies

The Traffic Policies Page

An Auto Configure functionality is also available to automatically create a recommended configuration for the Traffic Policy by leveraging on the protocols/hosts seen by ntopng for the devices belonging to the Pool (please note ntopng should run for at least 1 day in order to get the best results). Please note that this configuration is a guess and should be manually fine tuned. This feature is particularly useful in case of devices which are supposed to use a limited/static set of services, which is the case of IoT devices for instance. In this case the Default Policy is set to Drop (Default Deny) and the Auto Configure functionality adds those L7 protocols and hostnames which are actually required for the device to work (according to the historical data). In order to populate Host Rules, the Top Visited Sites euristic should be enabled under Settings > Preferences > Applications.

Auto Configure Traffic Policies

The Auto Configure Feature