A well-trained hacker always has a chance at breaking through your wireless encryption, getting on to your network, sniffing packets and decrypting your network data. However, it is unlikely that one will get through as long as you maintain security best practices and minimize exposure. You only have to worry about computers that are turned on: computers in sleep mode deactivate all networking hardware and are safe from attack.
Wi-Fi Password Cracking and WEP
A hacker won't have any problem getting on your network and intercepting encrypted data packets if you haven't established a password. The Wi-Fi password is the first line of defense against a hacker attack. Microsoft recommends using the WAP and WPA2 network encryption protocols to protect your wireless network from hackers and to keep people from piggy-backing off your connection without permission. The WEP security protocol can be cracked a just a few minutes because of a design flaw in the encryption, so you should avoid using the standard if you want to keep hackers out. The original WPA standard can also be cracked through an exploit in a few hours, but offers much more protection than WEP. According to PC World, WPA2 is difficult enough to crack that it is sufficient for home and small business use.
Passwords, however, can still be cracked or guessed: once a hacker knows the password, he won't have any problem getting into your network. The next layer of protection is to make sure the password is difficult to guess because a hacker can use what's called a "brute force" hack that guesses every possible password as quickly as possible until one is able to get through. The hardest passwords to crack are strings of at least eight lowercase letters, uppercase letters, numbers and symbols. The longer the string the better.
Network Analyzer and Secure Protocol
After a hacker accesses your network he may use a network analyzer, or packet sniffer, to intercept network traffic. Network analyzer programs were designed to follow network traffic and identify connection problems, but hackers can use them maliciously to record all information that's passed over the network. A hacker can use the collection information to gather things like account names, passwords and any personal information that's thrown across the network. The best way to work around network analyzers is to use protocols like secure FTP when moving files and secure HTTP when logging into websites, to make any data a hacker pulls worthless.
Firewall and Network Settings
Hackers may attempt to directly attack your computer over an encrypted Wi-Fi connection that they've managed to work around. A program called a firewall can thwart a direct attack by blocking any unauthorized data requests from the computer; every version of Windows as of Vista includes a built-in firewall. Additionally, Windows uses a program called HomeGroup to control computer hard drive access: if this is configured, only computers that have the HomeGroup key can view the other computer's files.
- PC Magazine: Definition of: Network Analyzer
- Computer Hope Jargon: Sniffing
- Veracode: Wireless Sniffer
- Netgear: What is WEP Encryption for Wireless Networks
- Computer World: Don't Use WEP for Wi-Fi Security, Researchers Say
- Microsoft Windows: Set up a Security Key for a Wireless Network
- Ars Technica: How I Cracked My Neighbor's WiFi Password Without Breaking a Sweat
- PC World: Lock Down Your Wi-Fi Network: 8 Tips for Small Businesses
- PC World: How Safe is WPA2-Secured WiFi
- Microsoft Security: Create Strong Passwords
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