using wireless internet without security

Some families in my neighbourhood are using wireless internet without any
security.



I know that using security (password or Mac-address filtering) is often
advisable, but I would like to know better what risks are involved by having
an open wireless network:

1) Can virus spread across a wireless network between computers which are
only sharing the internet connection?



2) Is it possible for users sharing an internet connection to gain access to
files on other computers sharing the connection?



Thank you

Erik

"Erik" <erikbach-fjerndette-@stofanet.dk> writes:

> Some families in my neighbourhood are using wireless internet without any
> security.
>
>
>
> I know that using security (password or Mac-address filtering) is often
> advisable

MAC filtering is very easily bypassed by anyone other than casual
snoopers. The same can be said of WEP encryption which can be
broken in minutes using freely available tools.

>, but I would like to know better what risks are involved by having
> an open wireless network:
>
> 1) Can virus spread across a wireless network between computers which are
> only sharing the internet connection?

Absolutely, but that's an issue orthogonal to the whole wireless
equation, and more a risk of putting a group of computer on the same
network.

However, if you lack a hardware firewall or home office router today,
you'll be adding no additional risk of network based piece of malware
spreading to you from the internet right now. If you have a "software
firewall" or are using windows firewall on your machine already, and
if you configure it not to trust computers on your local area network,
you'll be in as good a shape as you are against internet based attacks
today.

> 2) Is it possible for users sharing an internet connection to gain access to
> files on other computers sharing the connection?

Absolutely. With similar caveats above though. The difference
between an internet based threat and one of a local area network is
often in how the packet filter software ("software firewall") is
configured. Many of these programs trust the computers on your LAN
implicitly, which if file sharing is being used, would leave them open
to a neighbor jumping on the open access point.

Other more worrisome things, however, would be johnny neighbor jumping
on the open access point, running script kiddie attacks against
goverment networks, then men in black start knocking on the front door
inquiring about the illegal hacking activity originating from that
internet connection.

If you want to frighten the neighbors into action, that's the threat
that's most compelling. And add that with directional antennas, the
attacker could be up to a mile away.

WPA security with a strong, random, long passphrase is what they
should implement. Don't bother with WEP or MAC based filtering, and
SSID hiding tends to cause the legitimate owner more headache in
getting legit computers configured than it provides in any obscurity.

Best Regards,
--
Todd H.
http://www.toddh.net/

On 12/8/2006 7:24 AM, Todd H. wrote:
> "Erik" <erikbach-fjerndette-@stofanet.dk> writes:
>
>> Some families in my neighbourhood are using wireless internet without any
>> security.
>>
>><SNIP>

> WPA security with a strong, random, long passphrase is what they
> should implement. Don't bother with WEP or MAC based filtering,

Unless your hardware does not support WPA, then use what you have. Even
though it is easily broken, you should be using something until you
replace the hardware. And you *should* replace the hardware if it does
not support WPA

On 12/11/2006 11:32 AM, Sebastian Gottschalk wrote:
> John Hyde wrote:
>
>>> WPA security with a strong, random, long passphrase is what they
>>> should implement. Don't bother with WEP or MAC based filtering,
>> Unless your hardware does not support WPA, then use what you have.
>
> What a nonsense.
>
>> Even though it is easily broken, you should be using something until you
>> replace the hardware.
>
> Because it's easily, it's not "something" at all.
>

You know the story about the bear? WEP is like the red sneakers. It
won't stop an even moderately deterined attacker, but it will keep the
neighbor kid who does not know about cracking tools out of it. Even an
attacker will likely go after the easy targets first. Besides, I did
say replace it, right?

What's all this other stuff in addition to "WPA"? I set my router to:
WPA-PSK [TKIP] + WPA2-PSK [AES] Does all that additional stuff add to
security?

Thanks
RH

Roger Hammonds <roger@cox.net> writes:

> What's all this other stuff in addition to "WPA"? I set my router to:
> WPA-PSK [TKIP] + WPA2-PSK [AES] Does all that additional stuff add to
> security?

Not appreciably, no.

Biggest determining factor in your security using WPA with a
pre-shared key (PSK) is how long, random and complex the passphrase is
that you select for the pre-shared key.


--
Todd H.
http://www.toddh.net/