The development of the 802.11n common wireless networking standard has been associated with many controversies. The release of the final version has been delayed. Online forums were buzzing, because the quality of the test equipment left a lot to be desired. Network administrators did not deploy the devices, fearing that they would not be compatible with the final version of the standard. In September 2009 the new standard has been finally approved by the IEEE (Institute of Electrical and Electronics Engineers). The first mobile devices using this technology are already on the market. The wireless cable speed has become a fact.
Wireless cable speed
The new devices can provide physical data throughput rate up to 300 Mbps, i.e. almost six times faster than previous wireless networks. For the end user it can mean the actual rate up to 150 Mbps – the speed achieved in cable networks. “So far, each new wireless networking standard has been a step forward. Now, it is a real leap forward in technology,” explains Mariusz Jaworski, Project Manager and Senior System Engineer at Consafe Logistics. The 802.11n standard is a complete new approach to data transmission in common computer networks. The MIMO (Multiple Input, Multiple Output) technology, in which signals can be sent and received by multiple sources, enables very effective data transmission. The new standard is faster, less interference-prone and coves wider range. According to the technical specification, the devices can operate four channels simultaneously – currently available hardware uses only two channels.
Traditional technologies used channel width of 20 MHz to transmit data. The new standard provides wider data transmission channels (40 MHz) using channel consolidation, which means greater throughput rate. Apart from this, the new standard enables also data transmission in the 5 GHz band, which is a yet another key advantage of the 802.11n standard. The 5 GHz band is much less common than 2.4 GHz. This means fewer problems with data transmission interference, and lower risk of network break-ins. When you buy an IEEE 802.11n-compliant device, you can be sure you can use the 5 GHz band.
New transmission quality
There are no devices supporting the new standard yet, but the Wi-Fi Alliance assures its backward compatibility. This can enable gradual migration to the unified solution. Apart from that, there are extension cards available (PCMCIA, ExpressCard, and PCI-E or PCI) that you can use to fully exploit high transmission rates. "The development seems irreversible. The official publication of the standard by the IEEE signifies proliferation of the new technology," argues Jaworski. "There will be no more changes. When a customer requires wireless transmission of large amounts of data, this is the best solution."
The previous transmission speed has been fast enough to enable common online activities (such as Web browsing, e-mail and standard data transfers). But the rate of 54 Mbps means that the actual transfer rate is 22 Mbps – too low to support multiple concurrent broadband operations (servers, multimedia players etc.). High-definition multimedia transfer is now just a matter of time, and many devices do not tolerate any transfer delays. Telephone calls using the VoIP (Voice over IP) do not require a very fast connection, but rather a permanent, uninterrupted broadband link, which can help avoid signal interference and suspending or disconnecting calls. Built-in 802.11n adapters are already available in most laptop computers.
The new standard will prove useful in environments with high-capacity network requirements, when cabling is expensive or impossible. In an enterprise, 802.11n networks can be used in the office or for monitoring purposes, e.g. for industry equipment, such as cameras or sensors installed on the production lines, providing large amounts of data. Operating on the 5 GHz band with less congestion could be another advantage of the "n" standard’s implementation. However, for logistics applications, this is also possible with the "a" standard, where the rate of 54 Mbps is sufficient enough, and there are compatible mobile devices equipped with a barcode scanner available.
The race continues
Of course, the wired still moves faster than the wireless. Currently, copper cables with speeds of 1 Gbps are becoming increasingly popular, but perhaps in the near future, wireless connections of such speed will be also available. Some years ago, when a new technology has been developed, it was implemented in silicon chips and offered at a high price. But the technology has evolved incredibly over the years. Pentium III processors, costing a fortune ten years ago, now became simpler than mobile phones. Engineers have changed their approach to new technologies – things that once seemed impossible to be put into practice today are available for every household.
The same applies to 802.11n. The wireless transmission adapters used to be quite expensive, now they cost just a few dollars. Four complete transmission channels are not a problem anymore. At the end of the day, the new solution may turn out to be a dollar more expensive, but it could provide a great improvement in capacity. In some particular environments, a high speed wireless connection may be the only available solution.