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Securing Wireless Networks & More

Wireless fidelity (Wi-Fi) penetration is growing by leaps and bounds with, not only business houses, but also a lot of residential users opting for this facility. As most households nowadays, have a laptop along with a desktop, it makes sense to have a Wi-Fi router within homes for flexible internet access. As with the internet, proliferation breeds vices. If the number of cyber-crimes occurring in the country is any indication to go by, the possibility of unsecure Wi-Fi networks being compromised is also high.

Just a year ago, an American citizen, Kenneth Haywood, residing in Navi Mumbai didn't secure his Wi-Fi connection. The result — hackers accessed Mr. Haywood’s account to send a terror email. What followed made front page news in the city's dailies. Police personnel carried out mock Wi-Fi security checks. Awareness campaigns were launched to inform people to secure their Wi-Fi networks. But till today that message has somehow not really penetrated. The next victim is just around the corner. Unsecure Wi-Fi networks can make you lose much more than just your internet bandwidth and money.

Tech Guru Wi-Fi security test

We went to societies in and around our residential area to check for open unsecure networks. We used a Gateway netbook for the test which has an internal Wi-Fi network adapter. We did not hack into any account by second guessing the user name / passwords or used any tools to gain entry into a Wi-Fi hotspot. The test was very basic where we just used our netbook to check for any open unsecure network. Once an unlocked network was recognized, we opened it. After surfing the web for some time to check if the security of the network could be breached, we disconnected.

As expected we came across two open wireless networks having speeds up to 54Mbps. These networks had absolutely no security. They showed up as unsecured networks when the wireless connections page was refreshed. So many people are still ignorant of security regarding their wireless networks. A study conducted by the Data Security Council of India and Deloitte states that over 80 per cent of the wireless networks across the country (out of the 35,000 networks tested) are vulnerable to attacks.

Wi-Fi Jargon

It’s the process of scrambling legitimate information using algorithms called ciphers, such that the information can be decrypted only by someone or something that has the encryption key.

Service Set Identifier (SSID)

It is a name that identifies a particular 802.11 wireless LAN network. For the client machine to connect to the network its SSID should match with that of the router.

War Driving

It’s the act of locating and logging onto wireless access points from a moving vehicle using a laptop or a PDA or a cell phone.

Common Wi-Fi Hacking software
  1. NetStumbler : A Windows-based tool used to locate open wireless networks
  2. Kismet : Displays SSIDs that are not broadcasted
  3. Airsnort : Cracks WEP encryption keys
  4. Cowpatty : Cracks WPA- pre-shared key
  5. Wireshark : Sniffs data transferred over a wireless network
What the law says?

We spoke to Attorney at Law and Chairperson - Cyber Laws Consulting Center on the subject. Here’s what she had to say: "Under the IT Act 2000 there is no provision as such, to fine individuals who leave their Wi-Fi connections unsecure. But if a terrorist uses the open network to conduct his nefarious activities, then the owner may be called in for questioning. The user has to ensure that his connection is secure and should invest some time in securing the network. Leaving your Wi-Fi network open is analogous to leaving a signed cheque book unattended. It’s vulnerable to misuse."

Encryption woes

Data transfer over wireless networks is in the air and not confined to any wire. Due to this it is easy for a hacker to snoop into the information that is being transferred over the wireless network. To prevent this there is a need to encrypt the data in a way that it can only be deciphered by someone who has the decryption key.

Now the wireless routers have two kinds of encryption: Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA). WEP is considered to be a weak encryption mechanism as it has many loopholes. It uses 64-bit or 128-bit security keys to encrypt data of which 24-bits are called Initialization Vector (IV hereon). Since 24-bits give only 16.7 million variations, it is comparatively easier to decode the keys. Also the possibility of using the same IV key more than once is high making the system vulnerable to hack attacks.

WPA on the other hand is considered much safer than WEP because it has a 48-bit IV which gives over 500 trillion variations, which is very difficult to crack. Also the IV keys are better protected and never re used. WPA2 is the advanced version of WPA. Since WPA is a newer technology it is possible that many routers may not support it, so the user needs to do a firmware update.

WPA Key can be enabled by going in the Wireless Setup tab and selecting WPA Security option. Using a Passphrase which is an alphanumeric keyword, we can generate one or more WPA keys. The passphrase should be greater than 16 alphanumeric characters and should only be known to the administrator.

Plugging the loopholes

The hackers take advantage of the many loopholes that users tend to overlook while securing their Wi-Fi networks. Configuring the security settings on your Wi-Fi router is time consuming.

Administrator password
All the routers are shipped with default factory settings which many users do not change, while connecting to the internet. These default settings are commonly known, as they are specific to manufacturers. The first thing you should do while setting the router is change the default username and administrator password, so that it is only known to you.

Enabling WEP or WPA Encryption

As discussed above, the need to scramble data while using a wireless network is paramount. You should activate the necessary encryption key. It is advisable to choose WPA or WPA2 encryption rather than WEP if your router supports it. To configure the WPA encryption you have to enter a unique passphrase.

Broadcasting SSID

SSIDs are public names of wireless networks. All the client machines communicate within a network using similar SSIDs. Router manufacturers generally give default SSIDs e.g. Linksys router will have a default SSID 'Linksys'. A user should change this default SSID. Broadcasting SSID is a feature that is ideal for businesses and mobile hotspots where users move in and out of networks. For home broadcasting SSID may make the system vulnerable to attack if the router is not protected by a username and password.

MAC address filtering

Media Access Control (MAC) address is identification for all the hardware connected to your network. In a home network where there are limited number of users it is better to find out the MAC addresses of all the machines connecting to the network (enter ipconfig/all in the command prompt to get the whole list) The administrator should then feed these numbers under the “permit only” tab in the Wireless Network Access tab. This will ensure that any system, whose MAC address does not pass the filter, will not be able to access the network.

Positioning the router

The range of wireless routers may exceed the boundaries of your house, but its strength reduces with distance. It is deemed best to have the wireless router inside the house rather than on the window so that there is very little leakage.

Switching off the router

This may seem a very trivial thing to be included in this section. But many users just do not bother to switch off the router when it’s not being used for a long period of time.