[SOLVED] Local Network Security

[Guest]

Hey I have a general question about local network security. I have been using a MacBook Pro for a while now as a note-taking tool for school.
Recently I've gotten into VPNs and am currently using Hamachi and running a local Minecraft server on it. Using another computer I am able to access the server not only on the Hamachi VPN, but also just on the LAN. Anyway all this to say, I'm able to access my computer from another computer on the same network.
At home this is no problem as our network is very secure, but at school, where everyone knows the password to the network and many devices are on all the time, I'm a little paranoid about getting a virus.
I have the built-in firewall running, but I'm still not sure exactly what ports are open and exactly how much access other users on the same network have.
I'm sure this sounds like a stupid question to any experienced networker, but is my computer secure? And if not, what steps can I take to secure it?

Cheers,
KAG

 

[wildwell]

You can test what ports your firewall is leaving open using the port pinging service called "Shields Up" by Gibson Research here: https://www.grc.com/x/ne.dll?bh0bkyd2

 

[Ijack]

I'd recommend that any OS X user who is worried about security (i.e. all OS X users) start by reading this article, which covers the basics.