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Wireless Network Security at Home
By Martin Felsky November, 2009
Table of Contents
Introduction......................................................................................................................... 1
Your Home Setup ............................................................................................................... 2
Dynamic IP Addresses........................................................................................................ 8
Summary of Best Practices ................................................................................................. 9
Introduction
“Judicial Information” is defined in the Blueprint^1 (with some exceptions) as “information gathered, produced or used for judicial purposes.” Judges working on draft judgments or communicating with colleagues about cases are creating and transmitting “judicial information” and in all cases, the same safeguards that would apply to protect that information in the hands of court administration should apply at home.
Many judges are suspicious that home wireless networking may not be very secure – but lack the technical knowledge to configure the network security settings properly. Documentation accompanying home wireless networking equipment is often incomplete, impossible to understand, or even misleading.
The bottom line is that without proper hardware, software, configuration and use, all the information accessed through or stored on your computer is vulnerable to unauthorized access.
This article is designed to address home wireless networking security issues in a practical and plain-language manner. Taking the easy, free and common sense steps outlined below will make your home network reasonably secure against unauthorized access. Be aware, however, that even with all the recommended best practices in place, your home network will not be 100% secure. For that reason, all sensitive data should be encrypted during transmission and that means using a VPN or websites that use SSL encryption. (You can recognize these by a URL that begins with https://.)
(^1) See Canadian Judicial Council, Blueprint for the Security of Judicial Information , Third Edition, 2009.
Your Home Setup
Home Internet service is accessible through the same wires (or satellite dish) that provide your land-line telephone and cable television services. For the purposes of illustration I will show you my own home wireless set-up, which is provisioned through my Bell telephone line, and show you the default out-of-the-box settings, most of which are seriously lacking in effective security protection.
Whether you access the Internet through your telephone or cable service, you need a router to connect your computer to the Internet. A router is a device that connects two networks – in this case, your home wireless network with the Internet. Depending on what equipment and system you use, your router could also be referred to as a residential gateway, a cable modem, or a DSL modem.
Bell Internet Gateway (front view)
Your router is plugged into the cable or telephone wall outlet. (So in that regard it is not “wireless”.) Once the router is connected to the wall outlet, you need to connect your computer to the router. There are two ways to do this: by a network cable (wired) or with a wireless connection. The only way your computer can connect wirelessly to the router is if it has built in or external wireless network card. See illustrations below:
Since my desktop computer is plugged into the router, I am not actually using a wireless connection at my desk, even though my router is a “wireless” router. However, the router is signalling its existence through the air and I can pick up the signal anywhere in or near my house, with my wireless network devices, for example, my laptop, which has a built- in wireless network card, or my Blackberry, which also has built-in Wi-Fi capability (in addition to its facility to access the cell phone network).
The security of home wireless networking involves protecting your signal and Internet account access against the intrusion of others. How is this accomplished? By configuring the router with software that is built into the equipment, and with networking software that is part of the operating system on each of your computers or handheld devices. We will begin by setting up a home wireless network.
Note : The following screen shots show how to set up a wireless network with a Windows XP computer, and using Bell as the Internet Service Provider (ISP). Please refer to the Appendix to find information about other options.
Setting up a wireless network
On a Windows XP computer, you can establish a home network with the Microsoft Wireless Network Setup Wizard, as illustrated above. For other operating systems, refer to the appropriate manual or obtain assistance from a qualified IT support specialist.
The first step to securing your wireless home network is to change the name of the network that is built in. That is called the default SSID, which stands for s ervice s et id entifier. Change it to something that will not identify you. For example, “Felsky” or “1500 Maple Avenue” are not secure SSIDs because they divulge personal information.
Name the network
On the screen above you also have the option of choosing “Use WPA encryption...” WPA stands for W i-Fi P rotected A ccess. Even if an upgrade is required (for example, you may have an older notebook with a built-in wireless networking card that does not support WPA encryption), you must choose WPA^2 and never leave the older WEP^3 setting – or even worse – no encryption at all – to remain. (For this illustration I left my network SSID as “Bell053” (the default) and I did not enable WPA encryption.)
My network appears first on a list of networks (below) that are available in my neighbourhood.^4 You can see that there’s a fairly strong signal from “Toto.” My neighbour’s dog is called Toto so I’m pretty sure I know whose network that is. I also see that my neighbour has enabled WPA encryption. You can see that other neighbours who use Bell Internet – Bell666 and Bell861 have kept their default SSIDs and have not enabled WPA encryption, making them easy targets for hackers.
The practical result is that anyone with a wireless device or sniffer can see this list of available networks (roaming around the neighbourhood looking for unprotected signals is called “war driving”) and with readily available technology can (a) use my Internet account to do their own surfing, perhaps to send spam, and (b) see whatever unencrypted text is being sent to and from my computer.
(^2) It has recently been reported (August 2009) that WPA encryption can be cracked in one minute – but only
with the most sophisticated tools. See http://tech.yahoo.com/blogs/null/147906. (^3) WEP stands for W ired E quivalent P rivacy, and was intended to provide the same level of privacy as a
wired network. It can be cracked easily. (^4) One aspect of security involves placement of your wireless router – if you place it near an external wall, it
is easier for neighbours to gain access to a strong signal. If you are to place the router more centrally within your home, the signal will be weaker for outsiders.
which means that someone gaining access to my network could readily change all the settings on my router and lock me out. Always set a strong Administrator password for your network settings.
BAD PRACTICE: Administrator Password Not Set
On the following screen you can see that “SSID broadcast” is enabled. When SSID broadcast is enabled, neighbours can see your network name on the list of available networks. This increases the likelihood of being hacked. If SSID broadcast is not enabled, then your network SSID does not appear:
SSID broadcast enabled
Enabling SSID
Dynamic IP Addresses
In order to share network resources (such as the router, or a printer, or shared files on a computer), each computer on your home network needs to have a unique IP address, or I nternet P rotocol identifier, just like a website. Your router has a unique web IP address, and all the devices on your home network can be assigned IP addresses automatically. This is done through a process called DHCP, which stands for D ynamic H ost C onfiguration P rotocol, and it is very convenient.
Any time a computer wants to access your home network, DHCP assigns it an IP address automatically. This makes it easy for unwanted outsiders to obtain a valid IP address for your network. It is a better practice to manually assign IP addresses to each computer on your network. In the illustration below, DHCP is enabled by default.
DHCP enabled
Enabling DHCP
