With a cable modem and an Apple Airport Base Station connected to my
computer, is there any way of preventing outsiders from accessing my
computer via the modem or via the Airport Base that doesn’t require
shutting down the computer when not using it. Are there any other
security risks against which I should protect my computer?

I am currently using a Power Mac G4 running Mac OS X 10.2. It is
connected to the Internet via a cable modem, with an Asante Cable/DSL
router installed between the modem and G4 as a firewall.

To enable my wife to access the Internet wirelessly from other rooms
in our house via the same modem, I have ordered a PowerBook G4 and an
AirPort Base Station for her use. (The PowerBook will have an AirPort
card installed, but the Power Mac doesn’t.)

When not using the Power Mac I have been leaving it in sleep mode
rather than  shutting it down, because restarting takes much longer
than waking it from sleep. I consider this a major convenience, and
hope there is some way I can continue this practice after installing
the Airport Base Station without exposing the computer to serious
security risks.

At present I am the “administrator” and sole “user” on the Power Mac
and do not use a password. I feel no need to restrict my wife’s access
to the computer, nor that of guests in our house. As I understand the
workings of OS X, I could provide security by establishing my wife and
me as separate users with passwords, but achieving security in this
manner would require logging out, which in turn would require
restarting, which I prefer to avoid if possible.

It would be convenient in some ways to establish my wife and me as
separate users on both Macs if it wouldn’t involve logging out and
restarting, but I feel no need to restrict my wife’s access, or that
of guests in our house, to either computer.

Hi khk-ga,

In your setup, you're fairly secured from Internet intrusions, mainly
due to your router.  If you haven't forwarded any unnecessary ports,
your router should not expose you to any unnecessary security risks. 
My only suggestion in that area is to ensure the firmware for your
Asante router at ( http://techinfo.asante.com/su_sw_int.htm ) is
up-to-date, in case any new security vulnerabilities have been
discovered.  If you need instructions on how to do this, please let me
know the model of your Asante router.

Now as for your AirPort base station, there are a few things you can
do to tighten security.  Normally, I would recommend MAC Address
restrictions (known as Access Control on the AirPort), however it
appears that AirPort’s Access Control lists only applies to the wired
portion of AirPort and doesn’t apply to wireless access.  This is
rather unfortunate since it’s highly effective and is one of the
methods I use to secure my wireless network at here at home.

However, encryption is still available and it should be used.  This
will force anyone who wants to use your wireless network to supply a
password before they can access anything.  To enable encryption,
you’ll need to open the AirPort Admin Utility.  Under the AirPort tab,
first change the Network Name if you haven’t already, to something
more discreet such as “SmithFamily” or “SmithWireless”.  Then check
the “Enable encryption (using WEP)” and click the Change Network
Password button.  Here, type in the password you want to use.  Also
from the AirPort tab, check the box beside Network Name, labeled
“Create a closed network”.  This makes your AirPort invisible, unless
a person knows your Network Name exactly.  This adds an additional
layer of security.

Now, all you need to do is configure your PowerBook’s AirPort adapter
with your Network Name and Network Password (also known as WEP key). 
To do this on your PowerBook, you’ll need to click the Settings
triangle in the AirPort application and check “Allow closed networks”.
 Then on the list of available networks in the “Choose Network” popup
menu, select Other.  Here, you’ll need to type in your Network Name
exactly as it is and it is case sensitive.  You’ll be prompted for the
Network Password when you connect to the wireless network.

Now, you should have a fairly secured wireless network.  You will not
need to set a password on your main Mac if you do not not wish to
although I would still recommend it if you have sensitive materials on
it.  If you have any problems with any of the above, please do not
hesitate to request additional clarification.

Good luck,
mrbuzz-ga



Additional information:

802.11 Security
http://www.oreilly.com/catalog/80211security/chapter/ch07.pdf

Re: Couple of things (ways)
http://teachers.net/mentors/apple_classroom/topic571/12.08.02.20.58.45.html

Designing AirPort Networks
http://download.info.apple.com/Apple_Support_Area/Apple_Software_Updates/English-North_American/Macintosh/Networking-Communications/AirPort/Designing_AirPort_Networks.pdf


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