Hosts
Hosts is a dropdown menu always reachable from the top toolbar that contains a bunch of links to host- related information pages. The dropdown is as follows:

The Hosts Dropdown Menu
Host-related information pages available have the following content
Hosts page shows all hosts seen
Networks page lists all networks — both local and remote — any seen host belongs to
Host Pools page has the list of the defined Host Pools
Autonomous Systems page presents all Autonomous Systems (AS) any seen host belongs to
Countries page shows hosts countries based on the information provided by MaxMind databases
Operating Systems page lists all host operating systems that have been detected. Detection is done using passive fingerprinting techniques
HTTP Servers (Local) page shows monitored HTTP servers, limited to local hosts only
Top Hosts Traffic page presents traffic of top hosts in order to typology selected;
All Hosts
All hosts that have been seen monitoring network interfaces are show here. Column headers can be clicked to sort results in descending (ascending) order of the clicked header. Additional sort options are available in the top right corner of the table. The table shown has several columns, including
IP address, with optional country flag and OS logo (if detected)
Location, either Local (the host belongs to a local network) or Remote (the host belongs to a remote network) — please note that this is not a geographical location
Alerts, with the number of alerts associated to the host
Name, having the resolved hostname (or a custom name, if set in any Host Details page)
Seen Since, with the amount of time it has lapsed since the first packet sent/received by the host has been observed
ASN, with the AS number (if available)
Breakdown, showing a bar that gives visual insights in the use of both traffic directions
Throughput, with the overall actual throughput of the host
Traffic, with the total traffic exchanged by the host

The All Hosts Page
Any host can be clicked to be redirected to its ‘Host Details’ page, which is discussed below.
Host Pools
Host Pools are logical groups of hosts that are described in detail in the “Network Interfaces” section of this document. This page show the list of defined and currently active Host Pools.

The Host Pools List Hosts Page
Each row of the table shows, for each pool, the following information:
The Pool Name as defined by the user during Host Pool creation
A Chart icon to access historical pool traffic timeseries. Historical pool traffic charts must be enabled from the preferences page and are a feature that is only supported in the Professional version.
The number of active hosts in the pool
The number of alerts detected as the sum of host alerts for each host in the pool
Seen Since, with the amount of time it has lapsed since the first packet sent/received by any of the hosts in the pool has been observed
Breakdown, showing a bar that gives visual insights in the use of both pool traffic directions
Throughput, with the overall actual throughput of the pool
Traffic, with the total traffic exchanged by the pool
Host pools can be configured from the network interface page.
Networks
Networks shows all networks discovered by ntopng.

The Networks Summary Page
For each network discovered ntopng provides the number of hosts, alerts triggered, date of discovery, breakdown, throughput and traffic. Network names can be clicked to display the hosts lists inside the network selected.
Autonomous Systems
Autonomous Systems shows all autonomous systems discovered by ntopng. Autonomous Systems require Geolocation enabled.

The Hosts Autonomous Systems Summary Page
Ntopng uses a Maxmind database to gather information about Autonomous Systems (AS) and based on this it groups hosts belonging to the same AS. AS number 0 contains all hosts having private IP addresses.
Countries
Countries page provides all countries discovered by ntopng. Any country can be clicked to be redirected to a page containing the full list of hosts localised in that country. Countries require Geolocation enabled.

The Hosts Countries Summary Page
Operating Systems
Operating Systems page shows a list of all OS detected by ntopng. OSes can be clicked to see the detailed list of hosts.

The Hosts Operating Systems Summary Page
HTTP Servers (Local)
HTTP Servers page lists all local HTTP Servers. Multiple distinct virtual hosts may refer to the same HTTP server IP, which is specified in the second column. Additional information such as bytes sent and received are available for each HTTP virtual host. By clicking on the magnifying lens icon near to the HTTP virtual host, it is possible to display all active flows involving it.

The Local HTTP Servers Summary Page
Top Hosts (Local)
Top hosts page provides hosts activity on time basis. The page should be kept open in order to allow the graph to dynamical update itself with real-time freshly collected data for each host. The time axis is divided in 5-minute bars and goes backwards in time in a right-to-left fashion, starting from the present.

The Top Hosts Summary Page