ENTER THE WIRELESS MATRIX By Paul Montgomery "The Matrix is everywhere, it's all around us, here even in this room. You can see it out your window or on your television." MORPHEUS Imagine you can see electronic data as flowing symbols, like Neo in the Matrix films. What would you see if you turned on your "electron-vision" as you sit in front of your PC? Of course, you would see little green rivulets of data being passed through your PC's various internal wires, and you'd see packets streaming down your Internet-connected Ethernet cable, shielded from the outside world by layers of plastic. That's what wires are for, after all. But metal and glass are not the only mediums through which communication permeates. In the air around you would flow myriad other forms of data, streaming around and through you all the time. Some data would be old forms of communication, like AM and FM radio. TV signals would be bouncing off your bones, and military communications would go right through your body. Radio waves from satellites would have travelled from near-earth orbit to spray through your room like sunshine. The mobile phone you're carrying would send out little bursts of noise every now and again to announce its location. Maybe the key in your pocket would be preparing to unlock your car with a short staccato of radiation. If there's a remote control for a TV or other such device on your desk, it's getting ready to fire infrared light at you too. What does this all mean? Far from being an exotic or strange new technology, wireless networking is all around us already, and has been for over 100 years since the pioneering radio days of Marconi. Creating a wireless network for your home or office is not a case of exploring a new frontier; it's more like keeping up with the Joneses. Data-laden electrons are flowing around your environment like a glowing green Matrix thunderstorm. All you have to do is learn how to tap into the stream to use it for your advantage. BLUE PILL OR RED PILL? "I'm trying to free your mind, Neo, but all I can do is show you the door. You're the one that has to step through." MORPHEUS Before you enter the world of wireless networking, you have to ask yourself why you want to unplug your wires in the first place. Most people who are inclined towards making wireless networks in their home or business have already set them up, so it would be an unnecessary expense to rip up the cables from the ceilings and walls in favour of expensive new equipment. There is nothing wrong with keeping your wires. Cables have many inherent advantages over wireless technologies: they are relatively error-free; they don't bleed harmful radiation; they suffer far less from interference; they are reliable; and they are more secure. Admittedly, it is only a matter of degree on the last point since no network is wholly secure, as we'll find out later. Cost is always a consideration, and it is true that cables cost money. However, wireless networking equipment like network cards and hubs currently cost significantly more than their normal equivalents - as much as twice the price for a wireless access point as opposed to a standard 10BaseT hub, for instance. At this relatively early stage of the development of wireless hardware, it is not yet competing on price with well-established wire-dependent technologies. The main selling point for the wireless network is mobility. You can't beat wireless for portability. Why should the Internet be something you have to "visit"? You are already swimming in a vast ocean of radio waves sending data through your body every second, so why not go with the flow instead of having to restrict yourself to tapping in whenever you can connect to a piece of plastic? One of the design features underpinning the tremendous growth of the Internet is that it can spread out and infiltrate every device capable of communication. There is an inevitability that over time, every electronic device in your home and office will run on the Internet Protocol, and inevitably some of them will have to be connected wirelessly. The other strong suit of wireless is aesthetics. This is not just about getting rid of the bird's nest of cables under your desk, although that is a consideration. It's also about not needing to cut open your walls whenever you want to move your computer. Freedom from needing cable connections is invaluable for home networkers, especially in rented houses where it is usually difficult to get approval from the landlord to rip up the plasterwork. And then there is the cool factor: there is no denying that wireless networking is "in". WHAT IS THE MATRIX? "It's the question that brought you here. You know the question just as I did. It is a hacker's question." TRINITY Like all wireless communication, wireless networking for PCs uses a simple method of radio signal transmission called continuous sine waves. Radio waves are classified into spectrum ranges according to their frequency using a measurement called hertz that signifies how many cycles per second the electrons pass through in their sine wave pattern. For instance, FM radio signals operate in the range of 100,000,000 hertz, so that 107.5MHz (megahertz) on the FM dial represents a sine wave at 107,500,000 cycles per second. That's the theory, and for the most part it's not necessary to remember this system. Nevertheless, wireless networking comes in several different flavours, and the frequencies some of them operate in are different to others. For instance, IrDA is a protocol for transmission via bursts of infrared light at speeds of up to 4Mbps. Many laptops made over the last 5 years have infrared sensors built into them. However, IrDA has not really taken off due to the requirement to be in direct line of sight to communicate with other capable devices - this feature is useful for one-to-one communication, such as when a laptop or PDA synchronises its data with a PC, but not so useful for wider network scenarios. Most popular wireless protocols use the range between 2.4GHz and 2.48GHz, which has been set aside by international agreement for the use of industrial, scientific and medical devices - thus it is called the ISM band. Common wireless devices like baby monitors, garage-door openers and cordless phones all use the ISM band, so signals to and from wireless networking devices using this spectrum can be subject to interference. Of course, normal electronic interference like that from microwave ovens can also disrupt wireless signals. Two of the three sub-protocols under the 802.11 Ethernet standard use this part of the spectrum, as well as the newer Bluetooth specification. 802.11, WI-FI AND BLUETOOTH "How about some combat training?" TANK "Jujitsu? I'm going to learn jujitsu?" NEO Incompatible protocols are usually a curse, and wireless networking suffers just as much as other fields. Most of the standards in this field were set by the Institute of Electrical and Electronics Engineers (IEEE), whose group 802.11 gave its name to a series of specifications. As is often the case, an industry alliance of vendors filled in the market need for a slightly different protocol, which is where Bluetooth comes in. Most retailers that sell wireless networking equipment in Australia will only extend their product lines to hardware compatible with one or more of the four main specifications. 802.11a uses the frequency range above 5GHz, while 802.11b and 802.11g are both in the unregulated 2.4GHz ISM band. Bluetooth also works in the ISM band, but it is a significantly different technology. The most popular option for home and small office networking is 802.11b, mostly due to the low cost of its equipment. This variant, which is also known as "Wi-Fi" (short for Wireless Fidelity), runs at a maximum speed of 11Mbps. For business users, 802.11a is a viable option, for though the hardware is more expensive it is capable of much higher speeds of 54Mbps. The 5GHz band in which 802.11a operates also does not suffer from as much interference from other devices. These two variants were created at the same time to fill different needs, but 802.11g was only created this year, and is an attempt to have the best of both worlds: the 54Mbps speed of the "a" variants combined with compatibility with "b" hardware through using the ISM band. 802.11g hardware is only a little more expensive than the equivalent "b" device, where you would expect to fork out for price premiums ranging from 20 per cent to 50 per cent. MASTERING THE MATRIX "Hey, Mikey, he likes it! Ready for more?" TANK "Hell yes!" NEO When choosing which flavour of 802.11 to go with, it is a matter of horses for courses. If you're looking for the cheapest option, go with 802.11b. If you're looking for the highest and cleanest bandwidth possible, go with 802.11a. If you want the best of both worlds then 802.11g strides the middle ground. Bluetooth is another matter. The 802.11 standard is built on the assumptions of the established client/server model of networking, where multiple clients all communicate through a single server in a stable hierarchical model (this is why most wireless networks are said to be in "infrastructure" mode). Bluetooth-enabled devices do not automatically assume that they are a client or a server. Instead, they are constantly negotiating for control over each other in what is called "ad hoc" mode. Devices running Bluetooth organise themselves into personal area networks (PANs) of between two and eight devices in what is called "piconets", where one of the devices asserts itself as master and the rest become slaves. Bluetooth piconets run over a distance of no more than 10 metres at a speed of 1Mbps, although after headers and handshaking information is taken out the effective speed is only around 800Kbps. The implication of this design is that Bluetooth devices are not suitable for normal local area networks where laptops and desktop PCs need well-defined network routes. They are perfect for more focused devices, of course. HARDWARE "Okay. Store's open. What do you need? Besides a miracle..." TANK "Guns, lots of guns." NEO There are two ways of adding wireless capability to your laptop or desktop PC. The First is a wireless networking adapter, added to a PCI, AGP or PCMCIA port in just the same as you would add a 10/100BaseT network interface card for wired networking. The only difference is that instead of needing to plug a cable into a socket, you have a nodule sticking out of your computer somewhere doing the work for you. Prices for wireless adapters for each of the differing protocols are very close from vendor to vendor, since the components needed to construct them are very generic. The other option is a wireless-to-Ethernet bridge. This plugs into an existing Ethernet port, which is needed for devices that cannot have new cards installed in them. When setting up a network with one of the 802.11 flavours, you also need to buy a wireless access point, which fulfils the same function in your wireless environment as a hub or switch in wired networks - although when connecting back to an existing wired network, you would need to connect your access point to your wired hub or switch. Wireless access points, also known as base stations, are typically external devices with one or two fat antennae sticking up vertically. Prices for these devices can differ widely, as various vendors have different software management features or even patented technology to add ease of use or speed improvements. Hardware manufacturers are competing to boast how far their range goes, although all wireless networking devices degrade in speed the farther they are away from an access point. Many access points include support for DHCP, meaning that wireless devices connecting to it are assigned their own IP addresses. Getting your network set up for Bluetooth piconets is a little easier. All you need is a Bluetooth adapter, almost all of which use USB and retail for less than $100. The only other step is to buy devices that are Bluetooth-enabled. While the peer-to-peer nature of the protocol means it is not necessary to have a central server, it is possible to buy a Bluetooth access point to act like a traditional network hub. Depending on the capabilities of the devices, Bluetooth connections can function merely to synchronise data between devices, or act as gateways between devices or to the Internet, such as a laptop that gets to the net via a Bluetooth-capable mobile phone. GAMING "This is incredible. I know kung fu." NEO "Show me." MORPHEUS Console gaming is tailor made to become one of the most popular uses for wireless networking. Think of the issues involved: online console gaming needs a broadband connection, but broadband sockets are often installed in the "computer room" or a bedroom, far away from the main TV room. Wireless-to-Ethernet bridges can enable not only online access through a wireless access point, but also head-to-head play when two consoles with bridges connect to each other in ad hoc mode. Many wireless hardware manufacturers are now releasing bridges and adapters specifically targeted at the console gamer. The initial pricing for these bundles is noticeably higher than that charged for the basic hardware for normal customers, but the higher price often reflects the costs involved in adhering to standards such as Microsoft's Xbox Live Compatibility Logo. There is no guarantee without such certification that normal wireless bridges would not be incompatible with consoles, or at least require a lot of configuration to work correctly. The three online-capable consoles do not differ in the network configuration required to get them online with a wireless connection. With all three, the wireless access point or router is connected to the broadband modem (be it ADSL or cable), and then a bridge is connected to the console itself (note that you still need to buy the network adapter for the PlayStation 2). Management of network data is kept to a minimum, but is usually achieved through a Web browser interface. SECURITY "Once Zion is destroyed, there is no need for me to be here. Do you understand? I need the codes. I have to get inside Zion. You have to tell me how." AGENT SMITH So-called "white hat" hackers have a lot of fun with the media demonstrating the technique of "wardriving", where they drive around the streets of the CBD of a major city and see how many wireless networks they can tap into from the safety of their car. While this makes for good TV, a distinct lack of media reporting of these techniques being employed in the field suggests that it is not widespread. In any case, the equipment manufacturers have come to the party with several key technologies. You will find many wireless access points list "full WEP encryption" and "MAC address filtering" among their feature lists. The former refers to the Wired Equivalent Privacy protocol, which specifies a 128-bit encryption system for wireless transmissions. While encryption using 128-bit keys is at the low end of acceptable limits for safe encryption in the modern day, it is better than that used on most wired networks. The latter refers to a feature of wireless access points where they check against records of the MAC address of each wireless device they usually connect with - MAC addresses are unique to each device. Both of these features are at the level of tick-a-box these days in wireless hardware, with many vendors looking to proprietary features to give more assurances to users that their data is not being snooped on. One important thing to remember about security of wireless networks is that most of the security is not inherent to the transmission method itself - in other words, if the rest of your network is weak, it doesn't matter how open your wireless component is. Having said that, there is no need to ignore the basics: you could start by changing the default system ID of your access point, as well as the default administrator password, disabling identifier broadcasting to prevent hackers from even knowing you have a wireless system, and turning on the access point's internal firewall if it has one. Implementing sound procedures for your entire network will do a lot more for the cause of security than concentrating on whether a hacker is sitting outside your window peering at a glowing laptop screen... but then again...