Port 79 - finger

Nmap

nmap -n -sV -Pn -p- 192.168.0.102
...
79/tcp    open  finger     Linux fingerd 
...

Check if any user is logged on

finger @192.168.0.102

Other options

finger root@192.168.0.102
finger szalek@192.168.0.102
finger user@192.168.0.102