Doug,

You are falling victim to sales propaganda. The reps want to sell you
gear. Here is what they didn't tell you:

1. Wireless LAN MAC addresses are incredibly easy to sniff and spoof. If
your WLAN security plan is based solely on MAC address filters, you will
be cracked in less time than it takes to read this mail.

2. Unauthorized access is only a part of the problem. It is very
difficult, if not impossible, to prevent wireless sniffers from
receiving your wireless LAN packets (its radio - remember). Your second
biggest concern should be making those packets so hard to decrypt that
the cracker will eventually realize that its a waste of time to keep
trying. Basic WEP is not good enough - there are widely available
exploit tools that can crack any static 128-bit WEP key in less time
than it took me to write this response.

3. 802.11 can, in some cases, get better distance than Cat5 - especially
outdoors with directional antennas (up to 40 kilometers at 2Mbps).
Indoors, however, 802.11 signal strength/quality depends more on
construction materials and antenna choice than distance. 11Mbps at 200m
is based on ideal conditions, and is not likely unless the site was
built with wireless in mind. In fact, I have seen Wi-Fi deployments
where the client cannot get an intelligible signal at any data rate at
50m. 

4. It is less likely that a hacker will come sniffing in your
neighborhood. So, why would a hacker 'waste time' sniffing in your home
WLAN? Do you ever buy merchandise or services online at home? If so, do
you pay with credit card? If so, do you always verify that the site is
using SSL for transactions? Do you ever send or receive work-related
emails at home? If so, do these contain any sensitive information? If
so, are they always PGP-encrypted? There are lots of other reasons.

5. Here's one you didn't even think of - rogue access points. A hacker
sets up a hidden access point that spoofs your real access point. This
access point can now intercept your wireless traffic. In a basic
exploit, all a hacker would need to do is capture basic authentication
information to be successful. In a more advanced exploit, the AP could
even pass the traffic in what looks like a normal manner, gaining all
kinds of valuable information. The only prevention is mutual
authentication - the access point authenticates the client, and the
client authenticates the access point. 802.1x EAP/LEAP is designed to do
this.

MAC address filters are a good start, but nowhere near enough on their
own. To secure your wireless effectively, you need to either implement
802.1x EAP/LEAP (encrypted mutual authentication with dynamic WEP keys),
or deploy VPN (IPSec or PPTP/L2TP) on top of the wireless network.

Wireless LANs cannot replace wired LANs - at least not yet. At best,
they can significantly enhance LAN services, but only if deployed
properly and secured appropriately.

Lou

-----Original Message-----
From: Doug Wombles [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, October 17, 2001 12:01 PM
To: [EMAIL PROTECTED]; [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Subject: RE: Wireless LAN for the Home network.


I talked to several reps at a Technology Expo here last week about
wireless 
technology.  They told me that the latest wireless systems are based on
MAC 
address because of the problems experienced at trade shows.  They also
said 
that you can even set up the systems to ONLY give access to machines
with 
specific MAC addresses which eliminates the sniffers from getting in to
your 
network even if they do have your login/password.

Another thing they showed me was that the wireless system they were
using(I 
am sure it was top of the line to show how great it could be) was able
to go 
much further than Cat-5 cabling.  They were using it at about a 200m
range.  
Also, the signal was not affected by fluorescent lights, power lines or 
other normal forms of interference.

Besides, unless you live in an apartment complex or you work for the 
CIA/FBI, why would a hacker waste their time sniffing in a normal 
neighborhood in the hopes that someone MIGHT have a wireless network in 
their home they can hack into?

later
dw

>From: [EMAIL PROTECTED]
>To: [EMAIL PROTECTED]
>CC: [EMAIL PROTECTED]
>Subject: RE: Wireless LAN for the Home network.
>Date: Tue, 16 Oct 2001 13:05:05 -0400
>
>I am considering doing the same thing at home and have done a fair
>bit of research.
>
>What I have determined so far:
>
>1. Wireless is not very secure.
>
>2. If you are not careful on how you configure your bridge then
>someone outside of your house can *easily* connect, sniff and use
>your network. Just ask anyone that has done this at a trade show
>or airport and they can tell you it is very easy.
>
>3. It sure beats pulling wires so if you can deal with points 1
>and 2 then it is worth serious consideration.
>
>Best regards,
>
>Brian
>-----
>Brian Monkman
>Technical Program Manager, Firewall Certification
>ICSA Labs
>1200 Walnut Bottom Road
>Carlisle PA 17013-7635
>Phone:717.241.3263
>Fax:717.243.8642
>www.icsalabs.com
>
>-----Original Message-----
>From: Alan Wright [mailto:[EMAIL PROTECTED]]
>Sent: Sunday, October 14, 2001 3:03 PM
>To: [EMAIL PROTECTED]
>Subject: Wireless LAN for the Home network.
>
>
>Hi,
>Has anyone any specific do's and don'ts for a wireless LAN at home,
>I am looking at running the Buffalo Air station PCMCIA cards (2) in
>my sons desktop and my laptop, and the wireless bridge with router
>on he main desktop machine which is the machine with adsl coming
>into it.
>
>Currently running Win ME on the machine with ADSL on it but would
>consider upgrade to/or dual boot with Win 2K.
>
>Usual IDS suite running  ( snort, blackice defender, plus a couple
>of Ateliers progs )
>
>All the best
>
>Alan
>
>Alan J Wright B.Sc(Hons)(Open)
>SMS +47624462772.
>Email [EMAIL PROTECTED]
>[EMAIL PROTECTED]

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