Email Delivery

Receive new posts as email.

Email address

Syndicate this site

RSS | Atom


About This Site
Contact Us
Privacy Policy


November 2010
Sun Mon Tues Wed Thurs Fri Sat
  1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30        

Stories by Category

Basics :: Basics
Casting :: Casting Listen In Podcasts Videocasts
Culture :: Culture Hacking
Deals :: Deals
Future :: Future
Hardware :: Hardware Adapters Appliances Chips Consumer Electronics Gaming Home Entertainment Music Photography Video Gadgets Mesh Monitoring and Testing PDAs Phones Smartphones
Industry :: Industry Conferences Financial Free Health Legal Research Vendor analysis
International :: International
Media :: Media Locally cached Streaming
Metro-Scale Networks :: Metro-Scale Networks Community Networking Municipal
Network Types :: Network Types Broadband Wireless Cellular 2.5G and 3G 4G Power Line Satellite
News :: News Mainstream Media
Politics :: Politics Regulation Sock Puppets
Schedules :: Schedules
Security :: Security 802.1X
Site Specific :: Site Specific Administrative Detail April Fool's Blogging Book review Cluelessness Guest Commentary History Humor Self-Promotion Unique Wee-Fi Who's Hot Today?
Software :: Software Open Source
Spectrum :: Spectrum 60 GHz
Standards :: Standards 802.11a 802.11ac 802.11ad 802.11e 802.11g 802.11n 802.20 Bluetooth MIMO UWB WiGig WiMAX ZigBee
Transportation and Lodging :: Transportation and Lodging Air Travel Aquatic Commuting Hotels Rails
Unclassified :: Unclassified
Vertical Markets :: Vertical Markets Academia Enterprise WLAN Switches Home Hot Spot Aggregators Hot Spot Advertising Road Warrior Roaming Libraries Location Medical Public Safety Residential Rural SOHO Small-Medium Sized Business Universities Utilities wISP
Voice :: Voice


November 2010 | October 2010 | September 2010 | August 2010 | July 2010 | June 2010 | May 2010 | April 2010 | March 2010 | February 2010 | January 2010 | December 2009 | November 2009 | October 2009 | September 2009 | August 2009 | July 2009 | June 2009 | May 2009 | April 2009 | March 2009 | February 2009 | January 2009 | December 2008 | November 2008 | October 2008 | September 2008 | August 2008 | July 2008 | June 2008 | May 2008 | April 2008 | March 2008 | February 2008 | January 2008 | December 2007 | November 2007 | October 2007 | September 2007 | August 2007 | July 2007 | June 2007 | May 2007 | April 2007 | March 2007 | February 2007 | January 2007 | December 2006 | November 2006 | October 2006 | September 2006 | August 2006 | July 2006 | June 2006 | May 2006 | April 2006 | March 2006 | February 2006 | January 2006 | December 2005 | November 2005 | October 2005 | September 2005 | August 2005 | July 2005 | June 2005 | May 2005 | April 2005 | March 2005 | February 2005 | January 2005 | December 2004 | November 2004 | October 2004 | September 2004 | August 2004 | July 2004 | June 2004 | May 2004 | April 2004 | March 2004 | February 2004 | January 2004 | December 2003 | November 2003 | October 2003 | September 2003 | August 2003 | July 2003 | June 2003 | May 2003 | April 2003 | March 2003 | February 2003 | January 2003 | December 2002 | November 2002 | October 2002 | September 2002 | August 2002 | July 2002 | June 2002 | May 2002 | April 2002 | March 2002 | February 2002 | January 2002 | December 2001 | November 2001 | October 2001 | September 2001 | August 2001 | July 2001 | June 2001 | May 2001 | April 2001 |

Recent Entries

In-Flight Wi-Fi and In-Flight Bombs
Can WPA Protect against Firesheep on Same Network?
Southwest Sets In-Flight Wi-Fi at $5
Eye-Fi Adds a View for Web Access
Firesheep Makes Sidejacking Easy
Wi-Fi Direct Certification Starts
Decaf on the Starbucks Digital Network
Google Did Snag Passwords
WiMax and LTE Not Technically 4G by ITU Standards
AT&T Wi-Fi Connections Keep High Growth with Free Service

Site Philosophy

This site operates as an independent editorial operation. Advertising, sponsorships, and other non-editorial materials represent the opinions and messages of their respective origins, and not of the site operator. Part of the FM Tech advertising network.


Entire site and all contents except otherwise noted © Copyright 2001-2010 by Glenn Fleishman. Some images ©2006 Jupiterimages Corporation. All rights reserved. Please contact us for reprint rights. Linking is, of course, free and encouraged.

Powered by
Movable Type

« Intel Introduces Sonoma | Main | Sock Puppets »

January 20, 2005

My Evil Twin

It's the title of a They Might Be Giants song, and also a meme gone round the world: A number of people sent me links to articles about "evil twins" in the last couple of days. These articles are coining a new term for what has been called "soft APs" (software-based access points), a real problem that's been found in the wild for some time. These evil twins use software that creates a rogue access point which has the same name as a nearby network. AirDefense detected a number of these starting during their ongoing scan of the June 2004 Wi-Fi Planet Conference.

Because most operating systems are promiscuous by default, they will join any network with the same name as one they have joined before. If you're warned about joining network "linksys" the first time, you won't be warned the next. And there's nothing that helps you differentiate between a good "linksys" and a bad "linksys." If you have WEP or WPA encryption enabled, however, you won't be able to join an evil network because the key won't match. Public hotspots are really the biggest place to become a victim. (Glynn Taylor wrote in to note that the demonstration of this attack, Airsnarf, also includes a beta of a detection tool that notes whether an access point's characteristics have changed.)

This is why I highly recommend that all users of public networks employ some level of protection for any passwords that may travel across their networks. If you use SSL email client connections for POP, IMAP, and SMTP or an SSL-enabled Webmail site, just for instance, you're secured because an "evil twin" can't provide false digital certificate information to capture those sessions.

Web designers should always use Secure FTP (SSH over FTP), which is an encrypted form of FTP. If you don't know how Secure FTP works, find an ISP that does.

VPNs are now cheap and plentiful for rent. I recommend all the time because it's cheap ($8.88 per month and cheaper for longer pre-paid periods) and simple, working with software pre-installed on almost all platforms shipped in the last five years. You can also buy and install a Buffalo secure Wi-Fi gateway on your home or office network that offers full VPN protection for a small office for less than $200.

The 802.1X standard also alleviates this problem. If you log in over 802.1X, you'll be warned if you can't authenticate to a network. There are potential man-in-the-middle attacks, but properly monitoring certificate warnings works there, too. For instance, if I try to connect to my office AP, for which I've already accepted and installed a digital certificate confirming its identity, and an "evil twin" gets in the way, my 802.1X client warns me.

This is one reason, I'm sure, that T-Mobile was so eager to roll out 802.1X on their networks. Their client software has the root authority for their 802.1X service preinstalled for out-of-band trust that allows you to reliably only connect to their networks. Anyone trying to spoof a T-Mobile 802.1X-enabled AP won't get far.

One factor holding back public hotspot 802.1X deployment is that many hotspots use inexpensive access points that lack (or used to lack) the ability to operate discrete VLANs coupled with separate broadcast SSIDs. What this means is that T-Mobile can operate two logical networks--one protected by 802.1X and the other with a gateway page--without having to install two pieces of hardware. That was a missing piece that's now available, and this evil twin problem is practically a call to arms to hotspot operators to take a stand and start an 802.1X migration for their customers' benefit.

All this to say that we're about to see a dramatic acceleration in authentication and encryption that will bypass the utility of evil twins. The biggest factor holding us back? A lack of free legacy 802.1X clients for Windows 98 and Me, as well as flavors of Mac OS X and Linux. You can purchase clients for most older operating systems from companies like Funk and Meetinghouse, but because only Windows XP and Mac OS X 10.3 have built-in 802.1X mean that we have a migration ahead rather than a simple switchover.

4 TrackBacks

It sound like the plot of an old fashioned thriller, but the concept of rogue access points has a lot of buzz this morning, although some describe that as hysteria. I don’t think it is too major a problem, but... Read More

Here is an interesting article from the BBC site about fake Access Points. Something similiar on Wi-Fi Networking News "People using wireless high-speed net (wi-fi) are being warned about fake hotspots, or access points. The latest threat, nicknamed ev... Read More

Here is an interesting article from the BBC site about fake Access Points. Something similiar on Wi-Fi Networking News "People using wireless high-speed net (wi-fi) are being warned about fake hotspots, or access points. The latest threat, nicknamed ev... Read More

Phil Nobles, de l'université britannique de Cranfield, a identifié le nouveau risque majeur de Wi-Fi : de "faux" hot-spots publics et gratuits, installés dans l'intention d'écouter le trafic de leurs utilisateurs, de pénétrer dans leur machines ou... Read More

1 Comment

Excellent article!

There are a lot of locations that simply install a $30 access point and call it a hotspot. Granted configuring 802.1x would be a challenge for the non-technical person, but is a no-brainer.

I think part of the problem is that wireless snooping or the use of "evil twins" is so non-invasive that people don't take seriously what they can't see or something that's not considered a tangible threat.

Hopefully they will read this article.