PBNJ is a network tool that can be used to give an overview of an machine or multiple machines by identifying the details about the services running on them. PBNJ is different from other tools because it is based on using a scan from nmap parsed to amap. PBNJ parses the data from a scan and outputs to a CSV format file for each ip address scanned.

However, PBNJ is able to handle additional scans and parse the data while only looking for changes. For example, if a machine was updated with a newer version of OpenSSH than was running when the first scan was performed, the CSV file would contain the difference of the scan. Very useful for vulnerability assessment and penetration testing.

It is included in Backtrack http://www.remote-exploit.org/index.php/BackTrack

Depending on what you need, PBNJ can do various things. It is able to give a layout of a class network. It can also be run as an automated scanning tool parsing the data to CSV format files and growing an in-depth view of a network over time.