What is WiFi? An Introduction to Wireless Networks for the Small/Medium Enterprise

Wireless Networking, WiFi, is not a new technology, but it is only recently that it has become mainstream. What are the benefits of wireless networks and should you be considering using it?

The advent of portable computing devices is one of the main drivers for the adoption of wireless networking. Today, around 50% of new laptops come wireless enabled out of the box. All of Apple’s latest line of laptops come with both wireless & bluetooth built in. Many Microsoft Windows laptops are similarly wireless enabled.

A powerful alliance of vendors joined together in 1999 to form the WiFi Alliance. You can be assured that any device approved by the WiFi Alliance will interoperate happily with any other approved device. The term WiFi has become corrupted in common usage to mean wireless networks in general, not just devices approved by the WiFi alliance.

Why adopt WiFi?

Today’s workforce, equipped with PDAs, laptops and other mobile devices, demand access to your network from wherever they are, without the hassle of a fixed network. WiFi allows your business to deploy a network more quickly, at lower cost, and with greater flexibility than a wired system.

Productivity increases too, since workers can stay connected longer, and are able to collaborate with their co-workers as and where needed.

WiFi networks are more fluid than wired networks. A network is no longer a fixed thing, networks can be created and ripped down in an afternoon instead of the days or weeks required to create a structured cable network.

Architecture

Wireless cards can operate in two modes, Infrastructure and Ad-hoc.

Most business systems use wireless in Infrastructure mode. This means that devices communicate with an access point. Typically the access point also has a connection to the company wired network, allowing users access to servers and files as if they were physically attached to the LAN.

Ad-hoc connections are direct connections between wireless cards. This type of connection is more common amongst home users, but if used by business users could have serious management and security implications.

Management

You can easily connect to a WiFi network anywhere within range of an access point. This is a boon for your workers, but unfortunately, it also brings with it a few headaches for the IT department.

Security

Security is the bane of everybody who puts together a wireless network. access points, using factory default settings, are not secure at all.

So, if security is such a concern does that mean I shouldn’t deploy WiFi? No, it doesn’t. But it is something that you should bear in mind when in the planning stage.

When talking about security there is no such thing as having a completely secure system. Everything is insecure to some degree or other. The degree of security you require is dictated by the sensitivity of the information you possess.

If you require very high levels of security then you cannot rely on the built in security measures of a WiFi network alone.

On the other hand, most small to medium sized companies do not require very high levels of security. In which case you may use the standard WiFi security measures.

If you already have a wireless network you may be concerned about whether it is secure. There are four things you can do to ensure that you are secure.

1. Make sure that your access point(s) are not broadcasting the SSID (basically an identifier for your network). Whilst hiding your SSID isn't a security feature because it can be discovered quite easily anyway, it will stop casual bandwidth stealers from using your network;
2. Make sure that your access point(s) are encrypting using the highest level of sucurity you can. For instance, if you access point supports WPA or WPA2 use it, don't just use WEP because it may be more convenient;
3. Buy a wireless intrusion detection system. A number of products are available designed to help you monitor the security of your WiFi network as well as who is using it. If you have a no wireless policy, a wireless intrusion detection system will also help enforce your policy;
4. If you have a high security requirement such as needing to be compliant with PCI DSS, then you should either ensure your network people are appropriately trained or hire a wireless consultant. You may also need to buy proprietary, non-standard access points from the likes of Cisco (although even some proprietary standards from the likes of Cisco have their problems). Unfortunately, this will substantially increase the cost of your wireless network and substantially increase the complexity of the deployed system.

Conclusion

If you take anything away from this article it should be this: you must switch on the security features on your access points. Do NOT just switch on your access point, configure the IP address and then assume that everything is OK. It may well work, but it is NOT secure.

WiFi is seductively easy to use, don’t let your guard down just for want of a few minutes configuring your access points.