Cisco Systems WMA11B manual Appendix B Wireless Security, Brief Overview, What Are The Risks?

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Wireless-B Media Adapter

Appendix B: Wireless Security

A Brief Overview

Whenever data—in the form of files, emails, or messages—is transmitted over your wireless network, it is open to attacks. Wireless networking is inherently risky because it broadcasts information on radio waves. Just like signals from your cellular or cordless phone can be intercepted, signals from your wireless network can also be compromised. What are the risks inherent in wireless networking? Read on.

What Are The Risks?

Computer network hacking is nothing new. With the advent of wireless networking, hackers use methods both old and new to do everything from stealing your bandwidth to stealing your data. There are many ways this is done, some simple, some complex. As a wireless user, you should be aware of the many ways they do this.

Every time a wireless transmission is broadcast, signals are sent out from your wireless PC or access point, but not always directly to its destination. The receiving PC or access point can hear the signal because it is within that radius. Just as with a cordless phone, cellular phone, or any kind of radio device, anyone else within that radius, who has their device set to the same channel or bandwidth can also receive those transmission.

Wireless networks are easy to find. Hackers know that, in order to join a wireless network, your wireless PC will typically first listen for “beacon messages”. These are identifying packets transmitted from the wireless network to announce its presence to wireless nodes looking to connect. These beacon frames are decrypted and contain much of the network’s information, such as the network’s SSID (Service Set Identifier) and the IP address of the network PC or access point. The SSID is analogous to the network's name. With this information broadcast to anyone within range, hackers are often provided with just the information they need to access that network.

One result of this, seen in many large cities and business districts, is called “Warchalking”. This is the term used for hackers looking to access free bandwidth and free Internet access through your wireless network. The marks they chalk into the city streets are well documented in the Internet and communicate exactly where available wireless bandwidth is located for the taking.

Even keeping your network settings, such as the SSID and the channel, secret won’t prevent a hacker from listening for those beacon messages and stealing that information. This is why most experts in wireless networking strongly recommend the use of WEP (Wireless Equivalent Privacy). WEP encryption scrambles your wireless signals so they can only be recognized within your wireless network.

Appendix B: Wireless Security

Figure B-1: Warchalking

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A Brief Overview

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Contents 802 GHz .11b Wireless- B How to Use this Guide Copyright and TrademarksTable of Contents Appendix C Planning Your Use of the Wireless-B Media Adapter For Setup List of FiguresUnplug the Power Figure E-1 XP Default Interface Introduction WelcomeWhat’s in this Guide? Wireless-B Media Adapter Back Panel Power Ssid your wireless network’s name Remote Controller Connection to a Wired Network for Setup OverviewConnect the Power Setting up the Wireless-B Media Adapter Running the Setup WizardWindows Installer Screen License Agreement Screen Connection for Setup Screen 10 Connection after Setup Screen 12 Basic Wireless Settings Screen 13 Wireless Security Settings Screen Using the Adapter Utility Using the Utility’s Icon in Your PC’s System TrayUsing the Start Menu Media Folder ManagerMove the Adapter and its power adapter to the TV InstructionsConnecting to Your TV and Stereo Connecting to Your TV Only Connecting the Adapter to Your NetworkPlacement Options Vertical PositionUsing the TV Setup Installing the Adapter Utility10 Microsoft .NET Framework Package Screen Setting up the Adapter from Your TV 12 Select Music and Pictures Folders Screen14 Media Adapter Setup Using the Media Navigator Music MenusChoose Music All SongsMusic Options How to Play MusicNow Playing Now Showing Pictures MenuChoose Pictures How to Start a Slideshow with Music Picture OptionsHelp 12 Help ScreenAppendix a Troubleshooting Common Problems and SolutionsPicture won’t change on the TV Frequently Asked Questions What types of picture files can I show with the Adapter?What types of playlist files can I use with the Adapter? Can I play music from a CD using the Adapter? What Are The Risks? Appendix B Wireless SecurityBrief Overview Passive Attacks Jamming AttacksMaximizing Wireless Security Active AttacksDictionary-Building or Table Attacks Man-in-the-Middle AttacksWireless-B Media Adapter Ssid Wireless-B Media Adapter WEP Encryption Using the Adapter as Part of Your Wireless Network Using the Adapter as Part of Your Wired NetworkAppendix D Creating a Playlist Appendix E Setting a Static IP Address on Your PC Figure E-1 XP Default InterfaceFigure E-5 IP Address Click the OK button again to exit Network Neighborhood/My Network Places Appendix F Windows HelpShared Resources Appendix G Glossary Wireless-B Media Adapter Wireless-B Media Adapter Wireless-B Media Adapter Wireless-B Media Adapter Wireless-B Media Adapter Appendix H Specifications Standards Ieee 802.11b, Ieee 802.3, Ieee 802.3u PortsPower External, 5V DC, 2.0 a Certifications Operating TempStorage Temp Operating HumidityAppendix I Warranty Information Limited WarrantyAppendix J Regulatory Information FCC StatementIndustry Canada Canada Wireless-B Media Adapter Chapter K Contact Information
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