Best setup for privacy?

Question

I have two G5s, running osx 10.4.11. They are each connected a linksys wireless router, along with a printer and the internet connection.
My understanding is that to share, you turn file sharing to on, on both, and let them detect each other.
I would like to leave file sharing between the two computers on all the time so I can go from one to the other. But how can I best protect myself from outside access, without buying any other software? I don't want my neighbors accessing my computer.
Hooking them directly to each other is not an option, because it will cut off internet and printer access.
Thanks in advance.

Answer 1

The default Ethernet network connections are controlled through the
System Preferences> Network panel> where you can look into the
configurations and see what options are check-boxed to appear in
the main appearing selection (where enabled options appear as either
active or inactive) so you can shut off the wireless without removing
wires, from the System Preferences Network panel. Once you have an
option chosen here, you can also make changes to turn off the wi-fi.
Later, you could physically disconnect the wireless device attached to
the internet modem; or leave it attached and learn more about how to
have and maintain a secure wireless network. Perhaps by using the
MAC address of each machine to help more securely use the wi-fi.
And, not broadcast the name of your wireless network can help slow
down those who are simpler-minded about looking into visible networks.
You can also choose to change the DNS address (see ethernet setting
pane in Network) to what may be a more secure one than the ISP has.
I have not done this, but it has been said to help prevent some issues.
OpenDNS - Change your DNS (OS X Tiger)
https://store.opendns.com/setup/operatingsystem/apple-osx-tiger
Mac OS X 10.4 Help: Setting up a network connection
http://docs.info.apple.com/article.html?path=Mac/10.4/en/mh1152.html
Using the OS X Help section in your Finder menu bar, should allow
you access to information on how to change network settings. In
the Networks panel, in the area you can change the default and
choose other options to appear, you can also drag into priority status
what you may wish to have in an order of preference. This is basic.
Of course, an Ethernet cable would have to be attached between the
internet provider's cable/dsl modem and your computer for the default
network connections to be of service, if there isn't already one available.
The security documents cover a wider range of higher level info, if
you should choose to get them and read them over a period of time.
Good luck & happy computing!
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