The arp logger is a script that lives on monitor that every 5 minutes (*/5 * * * * in root's crontab) arping every ip in the 128.237.157.0 range. It then references this information to the switches at 128.237.157.253 and 128.237.157.254 using snmp.
The files consists of the follows on monitor:
- /root/network/scan.py: scans the network and calls snmp on 128.237.157.254
- /root/network/scan-2.py: scans the network and calls snmp on 128.237.157.253
- /var/lib/network.db: the database that stores the log information
There's also a webpage at http://monitor.club.cc.cmu.edu/mrtg/port.php that exposes this information