40

Appendix B: Wireless Security

Security Precautions

Wireless-G Access Point with Power Over Ethernet

Appendix B: Wireless Security

Linksys wants to make wireless networking as safe and easy for you as possible. The current generation of

Linksys products provide several network security features, but they require specific action on your part for

implementation. So, keep the following in mind whenever you are setting up or using your wireless network.

Security Precautions

The following is a complete list of security precautions to take (as shown in this User Guide) (at least steps 1

through 5 should be followed):

1.

Change the default SSID.

2.

Disable SSID Broadcast.

3.

Change the default password for the Administrator account.

4.

Enable MAC Address Filtering.

5.

Change the SSID periodically.

6.

Use the highest encryption algorithm possible. Use WPA if it is available. Please note that this may reduce

your network performance.

7.

Change the WEP encryption keys periodically.

To ensure network security, steps one through five should be followed, at least.

Security Threats Facing Wireless Networks

Wireless networks are easy to find. Hackers know that in order to join a wireless network, wireless networking

products first listen for “beacon messages”. These messages can be easily decrypted and contain much of the

network’s information, such as the network’s SSID (Service Set Identifier). Here are the steps you can take:

Change the administrator’s password regularly.

With every wireless networking device you use, keep in

mind that network settings (SSID, WEP keys, etc.) are stored in its firmware. Your network administrator is the

only person who can change network settings. If a hacker gets a hold of the administrator’s password, he, too,

can change those settings. So, make it harder for a hacker to get that information. Change the administrator’s

password regularly.

NOTE:

Some of these security features are

available only through the network router or

access point. Refer to the router or access

point’s documentation for more information.

41

Appendix B: Wireless Security

Security Threats Facing Wireless Networks

Wireless-G Access Point with Power Over Ethernet

SSID.

There are several things to keep in mind about the SSID:

1.

Disable Broadcast

2.

Make it unique

3.

Change it often

Most wireless networking devices will give you the option of broadcasting the SSID. While this option may be

more convenient, it allows anyone to log into your wireless network. This includes hackers. So, don’t broadcast

the SSID.

Wireless networking products come with a default SSID set by the factory. (The Linksys default SSID is “linksys”.)

Hackers know these defaults and can check these against your network. Change your SSID to something unique

and not something related to your company or the networking products you use.

Change your SSID regularly so that any hackers who have gained access to your wireless network will have to

start from the beginning in trying to break in.

MAC Addresses.

Enable MAC Address filtering. MAC Address filtering will allow you to provide access to only

those wireless nodes with certain MAC Addresses. This makes it harder for a hacker to access your network with

a random MAC Address.

WEP Encryption.

Wired Equivalent Privacy (WEP) is often looked upon as a cure-all for wireless security

concerns. This is overstating WEP’s ability. Again, this can only provide enough security to make a hacker’s job

more difficult.

There are several ways that WEP can be maximized:

1.

Use the highest level of encryption possible

2.

Use “Shared Key” authentication

3.

Change your WEP key regularly

WPA.

Wi-Fi Protected Access (WPA) is the newest and best available standard in Wi-Fi security. Two modes are

available: Pre-Shared Key and RADIUS. Pre-Shared Key gives you a choice of two encryption methods: TKIP

(Temporal Key Integrity Protocol), which utilizes a stronger encryption method and incorporates Message

Integrity Code (MIC) to provide protection against hackers, and AES (Advanced Encryption System), which utilizes

a symmetric 128-Bit block data encryption. RADIUS (Remote Authentication Dial-In User Service) utilizes a

RADIUS server for authentication and the use of dynamic TKIP, AES, or WEP.

IMPORTANT:

Always remember that each

device in your wireless network MUST use the

same encryption method and encryption key or

your wireless network will not function properly.

42

Appendix B: Wireless Security

Security Threats Facing Wireless Networks

Wireless-G Access Point with Power Over Ethernet

WPA Pre-Shared Key

. If you do not have a RADIUS server, select the type of algorithm, TKIP or AES, enter a

password in the Pre-Shared key field of 8-64 characters, and enter a Group Key Renewal period time

between 0 and 99,999 seconds, which instructs the Router or other device how often it should change the

encryption keys.

WPA RADIUS

. WPA used in coordination with a RADIUS server. (This should only be used when a RADIUS

server is connected to the Router or other device.) First, select the type of WPA algorithm,

TKIP

or

AES

. Enter

the RADIUS server’s IP Address and port number, along with a key shared between the device and the server.

Last, enter a Group Key Renewal period, which instructs the device how often it should change the encryption

keys.

RADIUS

. WEP used in coordination with a RADIUS server. (This should only be used when a RADIUS server is

connected to the Router or other device.) First, enter the RADIUS server’s IP Address and port number, along

with a key shared between the device and the server. Then, select a WEP key and a level of WEP encryption,

and either generate a WEP key through the Passphrase or enter the WEP key manually.

Implementing encryption may have a negative impact on your network’s performance, but if you are transmitting

sensitive data over your network, encryption should be used.

These security recommendations should help keep your mind at ease while you are enjoying the most flexible

and convenient technology Linksys has to offer.

43

Appendix C: Upgrading Firmware

Wireless-G Access Point with Power Over Ethernet

Appendix C: Upgrading Firmware

The Access Point's firmware is upgraded through the Web-based Utility’s Administration - Firmware Upgrade tab.

Follow these instructions:

1.

Download the firmware upgrade file from the Linksys website,

www.linksys.com

.

2.

Extract the firmware upgrade file on your computer.

3.

Open the Access Point’s Web-based Utility.

4.

Click the

Administration

tab.

5.

Click the

Upgrade Firmware

tab.

6.

On the

Firmware Upgrade

screen, enter the location of the firmware upgrade file in the field provided, or click

the

Browse

button to find the file.

7.

Click the

Upgrade

button, and follow the on-screen instructions.

Figure C-1: Firmware Upgrade

44

Appendix D: Windows Help

Wireless-G Access Point with Power Over Ethernet

Appendix D: Windows Help

Almost all wireless products require Microsoft Windows. Windows is the most used operating system in the world

and comes with many features that help make networking easier. These features can be accessed through

Windows Help and are described in this appendix.

TCP/IP

Before a computer can communicate with the Access Point, TCP/IP must be enabled. TCP/IP is a set of

instructions, or protocol, all PCs follow to communicate over a network. This is true for wireless networks as well.

Your PCs will not be able to utilize wireless networking without having TCP/IP enabled. Windows Help provides

complete instructions on enabling TCP/IP.

Shared Resources

If you wish to share printers, folder, or files over your network, Windows Help provides complete instructions on

utilizing shared resources.

Network Neighborhood/My Network Places

Other PCs on your network will appear under Network Neighborhood or My Network Places (depending upon the

version of Windows you're running). Windows Help provides complete instructions on adding PCs to your

network.