Home > Articles > Hardware > Upgrading & Repairing

Securing Your Wireless Network

  • Print
  • + Share This

Securing Your Wireless Network

In this article, you will learn about the security challenges provided by typical wireless network configurations and how to secure your wireless network against intruders.

Introduction

In 2003, one-third of all laptop computers sold included wireless Ethernet network adapters. May 2003 was the first month that laptop computers outsold desktop computers. Given these facts, and the increasing amount of retail shelf space devoted to wireless Ethernet network hardware for use on existing desktop and laptop computers, its likely that, sooner or later, you will have a wireless Ethernet network.

Wireless Ethernet Standards

Figure 1

Wireless Ethernet hardware meets one or more of the following standards shown in Table 1.

Table 1 Wireless Ethernet Standards

Official Standard

Maximum Speed

Frequency

Interoperable With

802.11b

11Mbps

2.4GHz

802.11g

802.11g

54Mbps

2.4GHz

802.11b

802.11a

54Mbps

5GHz

Although the term Wi-Fi is often used to apply to all wireless Ethernet hardware, it properly refers only to wireless Ethernet hardware which has been certified for interoperability by the Wi-Fi Alliance (www.wi-fi.org). See Figure 1 for an example of a product label found on Wi-Fi certified hardware.

If you have or plan to implement a Wi-Fi network it's important that you understand the security challenges involved in implementing a typical wireless network and how to secure your wireless network against intruders.

How an Unsecured Network Can Threaten Your Privacy and Identity

Typically, most vendors of wireless Ethernet access points and routers (access points connect wireless Ethernet devices to each other; routers connect local wired and wireless networks to the Internet) dont enable security settings in their default configurations. Routers are typically configured to broadcast their SSID values (the SSID identifies the wireless access point or router) to wireless clients, and are not usually configured to require any authentication from those clients.

When a wireless client detects an SSID which doesnt use security, all it takes to join that network is a couple of clicks of the mouse on the wireless network icon in the Windows system tray. Because Windows XPs built-in wireless Ethernet support scans for SSIDs, its easy for an unauthorized user to piggyback on an unsecured wireless network and do anything from borrowing an Internet connection to reading email or snatching documents from a shared folder on the network. Although the comic strip Doonesbury put an amusing spin on Wi-Fi gatecrashing in its July 21, 2002 strip, the potential for identity theft, loss of business trade secrets, and loss of privacy caused by unsecured wireless networks arent very funny in real life.

Why Network Security Is Usually Disabled by Default

Given the risks inherent in unsecured wireless access, why do most network vendors (Microsoft is a notable example) leave network security disabled by default? There are several reasons:

  • Enabling network security complicates wireless network setup. When security is enabled, both the access point or router and the network clients must be configured to use the same security settings. When different vendors products are used, it can be hard for users to determine exactly how to make the necessary changes.
  • Settings which dont match (such as incorrect encryption keys or encryption levels) prevent wireless clients from working.
  • Wireless throughput often drops when security is enabled, particularly on 802.11b (11Mbps) networks or networks which mix 802.11b and 802.11g hardware.
  • Network security settings are not needed for wireless adapters used with a public hot-spot, such as those now available in some public libraries and other locations. These networks are usually separated from internal networks, and are configured to provide Internet access only.

Configuring Your Router or Access Point for Security

You can secure your home or office wireless Ethernet network by using the features included with virtually any combination of access point/router and network adapter. These include:

  • enabling 128-bit WEP encryption
  • changing the default SSID used by the network
  • disabling broadcast of the SSID
  • enabling MAC filtering
  • using Wi-Fi Protected Access (WPA) when available

Most wireless access points or routers are configured through a web-based interface. Check the manual for your unit to determine what IP address to use in your browser to start the configuration process. Provide the username and/or password required to continue. Heres a tip: if your router or access point includes a wired Ethernet switch, you should connect it to a computer with a wired Ethernet adapter to configure it.

Enabling 128-bit WEP Encryption

Wireless Equivalent Privacy (WEP) is a type of encryption that all wireless Ethernet products support. WEP uses a fixed encryption key which a network client must provide before a connection can be made. Although a determined hacker can break WEP, enabling 128-bit WEP protects you against casual to moderate snooping.

Some early wireless Ethernet adapters dont support 128-bit encryption without a driver upgrade; check the manual for your adapter if youre not sure of the WEP encryption levels it supports. To enable WEP, select the encryption level within the access point or routers WEP configuration screen and enter the required length of encryption key in either HEX or ASCII (Figure 2). The higher the encryption level, the longer the key; longer keys are also harder to break. 128-bit encryption uses a 13-character key, while 256-bit encryption (used primarily in enterprise settings and not supported by most home-market wireless hardware) uses a 26-character key. Be sure to record the key, because it must be provided to each network client for access.

Figure 2

Changing the Default SSID

The Service Set Identifier (SSID) is used to identify the wireless network access point or router. Manufacturers store a default value for the SSID in the non-volatile memory of these devices. Even if the SSID is not broadcast, a hacker who discovers what brand and model of access point or router you have can use the default SSID to gain access to your network if it is not secured. Consequently, its a good idea to change the default SSID supplied with the device.

Disabling SSID Broadcast

By default, wireless access points and routers broadcast the SSID for detection by all wireless network clients in the vicinity. To help reduce intrusion attempts, you can disable this behavior in the device setup.

Figure 3 shows a wireless router after SSID broadcast has been disabled, but before changing the default SSID.

Figure 3

Enabling MAC Filtering

If you want to limit access to the wireless network to specific network adapters, some routers and access points offer a feature called MAC filtering. MAC filtering uses the media access control (MAC) number assigned to each network adapter to enable or block access to the network. If you dont know the MAC address of a particular adapter, you can use the Windows program Winipcfg (Windows 9x/Me) or the command-line program ipconfig /all (Windows NT/2000/XP) to display this information. Figure 4 shows how to use this information to configure your wireless access point or router.

Figure 4
(Click to Enlarge)

After you enable the network security features you want to use on your router, be sure you save the changes to the router or wireless access points non-volatile memory. See your product manual for details.

Upgrading to Wi-Fi Protected Access (WPA)

The biggest weakness in current wireless security settings is the WEP encryption key. Even if your network hardware supports 256-bit encryption, the key is a fixed key which could eventually be cracked by a determined intruder. Some wireless Ethernet hardware now supports Wi-Fi Protected Access (WPA), which uses a new dynamic keying method which generates trillions of keys from a single key entry. Unfortunately, although WPA was introduced in 2003, many vendors have still not upgraded their hardware to support it. Check with your wireless network vendors for hardware updates if your wireless access point/router or network adapters dont include WPA support. If a single device on your wireless network doesnt support WPA, you will need to continue to use WEP encryption instead.

Connecting to a Secured Network

After you secure your wireless access point or router, each client must be supplied the WEP or WPA key necessary to connect to the network. The key must be provided to make a connection. Figure 5 shows a typical connection dialog requiring a WEP key.

Figure 5

The first time you connect to a wireless network access point or router which uses WEP, you might also need to click the Advanced button to bring up the properties sheet for the connection. Select the connection and click Configure. Check the boxes for Data encryption and network authentication, then enter the network key and other information as prompted. Figure 6 shows this dialog. On subsequent connections, the key is stored for automatic access. You can just click on the wireless network shown in the available networks dialog to make your connection.

Figure 6

Conclusion

Wireless networking has become an extremely popular way to build home and office networks. However, wireless networks present extreme security risks unless the network is secured against invaders. Use the methods in this article to secure your network and upgrade the security as WPA becomes available.

For Further Research

Learn more about Wi-Fi Protected Access (WPA) from the Wi-Fi Alliances official web page:

http://www.wi-fi.org/OpenSection/protected_access.asp?

Fred Langas Langa Letter for Information Week on sharing a Wi-Fi connection discusses security and other issues. Read it at http://www.wi-fi.org/OpenSection/protected_access.asp?

US Robotics offers some useful white papers which discuss wireless access point and router features which improve security (requires Adobe Reader/Acrobat Reader). A business-oriented paper is located at http://www.usr.com/download/whitepapers/lan-security-wp.pdf. A white paper discussing including security features built into their 802.11g-compatible network products is located at http://www.usr.com/download/whitepapers/80211g-wp.pdf.

Copyright©2004 Pearson Education. All rights reserved.

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020