Raising Concerns

City or municipal networks have pressing security issues

• By Cosimo Malesci
• Apr 01, 2014

Wireless transmission is usually a topic that raises many concerns in the security world. It seems common knowledge nowadays that a wireless network can be easily hacked, and private information can end up on the Internet or someone’s identity can be stolen. This is a major concern at the consumer level. When you walk into a computer store looking for the latest wireless 802.11 access point, security and encryption features are written all over the box, and you will most likely end up buying whatever seems to have the highest level of encryption. Most of today’s home access points have advanced encryption systems mainly to prevent a neighbor from stealing a Wi-Fi connection.

Security and encryption becomes even more relevant in a corporate network where even the smallest breach could lead to a major security threat and millions of dollars in damages. Different from home networks, corporate networks get attacked on a regular basis, so a high level of security is needed. The issue is even more relevant for city or municipal networks since they could be controlling some key operations that could heavily affect a city and its safety.

The issue of network safety and security is real and an important one to keep in mind; however, the key question that needs to be asked is how network security and encryption on wireless differs from a wired network. The truth is: It’s not very different. Wireless networks are not necessarily less secure than wired networks. What people don’t realize is that sometimes it is easier to tap into a switch in a cabinet than to play around with wireless. So, let’s review some of the key things that should be kept in mind to make a wireless network secure.

Transmission protocols. Wireless networks can be divided in two groups: ones that use a standardized transmission protocol and ones that use a proprietary transmission protocol. A standardized transmission protocol, for example, is 802.11, 802.15 or Zigbee. It is a protocol that follows certain characteristics to guarantee interoperability between devices made by different manufacturers. Standard Wi-Fi connectivity is probably the best example of this. When you go to Starbucks and connect to the wireless network, it doesn’t matter if you are using an Apple or a PC, an iPhone or Android, or even a Blackberry because they all have a Wi-Fi-compatible interface that allows you to connect to the network.

This is great for public Wi-Fi and any network that requires compatibility with multiple devices; however, this also poses a threat when it comes to security, as there are numerous devices that can communicate with your network.

Consequently, if security is your main concern, you should try to look for a wireless network that uses a proprietary transmission protocol because this will strongly limit the number of people who will be able to access it.

Authenticated routing. Regardless of the type of transmission protocol you are using, authenticated routing will prevent other wireless devices from interacting with your network. This is a key feature on the majority of wireless devices, but, before committing to any specific solution, you should know if it offers authenticated routing and understand how it does it.

Authenticated routing is enforced with a passphrase that is needed for two access points to communicate. WPA and WPA-2 are two of the most common authentication standards on a Wi-Fi network and provide a reasonable level of protection. It also is worth noting that WEP is no longer a secure method to prevent hackers from getting into your network and should be avoided at all costs. WEP can be cracked in less than five minutes using any laptop and software that is readily available on the web.

Control user impact. Most security breaches are, in fact, due to lack of knowledge on the user’s part. One of the most common accidents is caused by the so-called Rogue Access Point, a standard open 802.11 AP that is wired into the network by one of its users. This needs to be prevented as it could jeopardize the overall safety of the network and create a very easy entry point for hackers.

Detecting Rogue Access Points is a feature that is usually present on most enterprise networks. In home or small office networks where consumer-grade access points are used, though, this feature is not present, so attention should be given to other people attaching access points to the network.

Filter the MAC addresses. This allows control over which devices have access to the network, thus preventing another unknown device from being able to connect. This also prevents unknown devices, such as laptops or cellphones, from connecting to the wireless access point and is an effective way to keep tabs on who uses the network.

Encryption. Usually accomplished using a built-in encryption module on the wireless device or by adding a VPN box to the network, the goal of encrypting traffic is to add an additional level of protection to the data traveling on the network to prevent people from being able to understand the information being transmitted.

Most devices on the market use AES-128 bit or AES-256 bit encryption. The AES standard is one of the most widely adopted encryption systems due to its high level of security.

When activating encryption, it is important to keep in mind network performance. Given the large amount of data processing needed for encryption, it’s usually recommended to use a device with a dedicated encryption module or a separate device to avoid creating an overhead on the network.

Limit the range of the network. Limiting the power output and controlling the coverage area by using directional antennas are very effective ways to reduce the number of people that could have access to the network and might try to hack into it. More power is not always equivalent to a better connection due to issues such as co-location interference that might be present in a network with more than one access point that are close to each other. Controlling the output power of the access point can be easily done through the user interface with just a few clicks.

Wireless networks can be very secure and reliable transmission systems as long as certain rules are kept in mind and adhered to. In addition to upgrading to the latest technology and encryption systems, employees’ knowledge goes a long way in making any network more secure, regardless of whether it is wired or wireless.

This article originally appeared in the April 2014 issue of Security Today.