Your simple guide to wireless

WIRELESS PERSONAL AREA NETWORKS

Bluetooth

What is it?
Bluetooth is a short-range radio frequency technology that transmits voice and data. It automatically locates and connects any enabled personal devices, such as laptops, mobile phones and keyboards.

Benefits?
Bluetooth devices are inexpensive, and create a small network that can automatically synchronise data held on appliances close to each other.

Limitations?
Bluetooth has a range of only 10 metres and a data transfer rate of just 1Mb, so is relatively slow compared with other wireless technologies. It operates at the 2.45GHz frequency, which is unregulated and used by everything from baby monitors to police radios. Bluetooth avoids interference using a technique called 'frequency hopping', but there are fears that performance may degrade if too many people use it at once.

When would you use it?
Bluetooth is used for connecting and synchronising data on personal devices in the office or at home.

WIRELESS LOCAL AREA NETWORKS

Wi-Fi

What is it?
Wireless Fidelity refers to any type of 802.11-compliant wireless network. Wi-Fi access points can support about 15 users up to a range of 50 to 100 metres.

Benefits?
Wi-Fi boosts productivity because staff can use computers or PDAs to access data and the internet from wherever is most convenient. The self-configuring technology is cheap and easy to install.

Limitations?
Wi-Fi networks are slower than wired networks, providing bandwidth of 54Mbps compared with more than 1Gbps for fixed-line equivalents. Wi-Fi networks do not offer guaranteed service levels, and performance can degrade quickly if too many people are trying to use them at once. There are limited numbers of network monitoring and management tools available, which can make support tricky, and access points and cards from different manufacturers may not work together.

When would you use it?
Wi-Fi networks eliminate cabling, particularly in new sites and in older, listed buildings where it is not possible to drill through walls. But Wi-Fi is also used to aid mobility and for public web access. Some organisations are Wi-Fi enabling conference centres and coffee shops, while many hotels, airports and other facilities are providing so-called hotspot access.

WIRELESS METROPOLITAN AREA NETWORKS

WiMax

What is it?
The term WiMax relates to the Worldwide Interoperability for Microwave Access group set up to promote the IEEE 802.16 Air Interface Standard, but is now used to refer to the wireless broadband network technology itself. WiMax can handle voice and data, internet connection and voice-over IP services, but the market is very new and the first certified products are not due until the end of this year.

Benefits?
WiMax has a theoretical range of 30 miles, but drops to between four and six miles in urban environments. Connection speeds are up to 70Mbps and users do not need to be in direct line of sight to a base station to maintain connectivity.

Limitations?
WiMax technology is expensive and there are no certified products on the market. It operates between 2GHz and 11GHz, but such a diversity of possible frequencies may impede adoption due to lack of global harmonisation.

When would you use it?
WiMax is expected to become a replacement for and extension to broadband technologies such as DSL, cable modems and leased lines in metropolitan areas. Some analysts believe that WiMax will replace Wi-Fi hotspots, while others expect it to take over from wired broadband as a means of connecting hotspots to the internet. Most expect it to be used by businesses to link remote offices, while the mobile WiMax standard, 802.16e, is seen as a potential threat to 3G because of its higher transmission speeds.

WIRELESS WIDE AREA NETWORKS

3G

What is it?
Third-generation wireless communications will combine the functionality provided by mobile phones, laptops and TVs into one device that can handle voice, data and video.

Benefits?
The technology provides an always-on broadband connection at speeds of 144Kbps to 2Mbps. It also enables global roaming, which means that 3G appliances will be usable anywhere in the world. 3G will extend the range of services offered by GPRS. Users will be able to fax, phone, send and receive large emails, surf the web and undertake high-speed online transactions. They will also be able to access corporate applications, participate in videoconferencing and receive TV broadcasts.

Limitations?
Billing mechanisms are immature and customers currently pay for how many megabytes of data they download, which isn't very meaningful, rather than charging on an event-driven basis, for example for each song or video game accessed. 3 is the only UK vendor with a public 3G service, but uptake is low and adoption of non-voice services has been slow. Vodafone and Orange have launched 3G data cards for laptops, and are expected to launch voice services in time for Christmas. But 3G penetration is not expected to hit more than 20 per cent before 2007, according to Forrester Research.

When would you use it?
3G is only being used by early adopters, although analysts expect it to become ubiquitous over the next five to 10 years.

GPRS

What is it?
General Packet Radio Service is often referred to as 2.5G. It is provided over existing mobile networks and can be accessed using mobile phones, PDAs or with a GPRS card in a laptop.

Benefits?
GPRS can transmit data at 64 to 144Kbps, compared with speeds of 10Kbps for traditional phones. It is relatively inexpensive and provides an always-on connection, allowing users to browse the web, undertake online transactions and send or fax large files and emails. Customers are charged for sending a data file based on its size and not on the connection time, so it is cheaper. Edge (Enhanced Data Rates for GSM Evolution), is similar to GPRS, but will provide data transfer rates up to three times faster, and improve service quality.

Limitations?
GPRS can only handle data and there is no storage mechanism, as with SMS. Older GSM mobile phones do not access GPRS services, so it is necessary to buy new equipment and subscribe to a suitable network.

When would you use it?
GPRS is useful for mobile workers wanting to access the internet or send or receive files, data or emails using their phones, PDAs or laptops.

Satellite

What is it?
Satellites orbit the earth and can handle any type of traffic from voice to data to images.

Benefits?
It allows communications in areas where the volume and size of traffic is too high for traditional wired or wireless networks, or where it is impossible to introduce them.

Limitations?
Satellite comms are generally too expensive to be used for anything other than specialist activities.

When would you use it?
Satellite technology is employed to handle large volumes of one-way traffic such as TV transmission, for communications with ships and aircraft outside the reach of terrestrial systems, and by workers based in very remote locations.

Forrester Research, the Burton Group and Datamonitor assisted in the preparation of this article.