Wireless protocols and technology are constantly changing -- increasingly affecting how we communicate. Wireless deployments are currently just one of many parts of an enterprise's network. As the protocols and technologies change, if current predictions come true, wireless could eventually replace wired networks completely. While waiting for these changes, administrators should take into consideration what is necessary to plan and...
deploy a wireless network. This guide encourages IT professionals to consider the changes to wireless that are fast approaching by explaining the components of wireless protocols and technology -- including 802.11 and its development, wireless access points and security and troubleshooting issues. Understanding wireless technologies, how they work and in what direction the leading trends are moving the field is an important base from which to start exploring how wireless can best suit your needs.
Wireless technologies defined
Wireless is a term used to describe telecommunications in which electromagnetic waves -- rather than some form of wire -- carry the signal over part or all of the communication path. The first wireless transmitters went on the air in the early 20th century using radiotelegraphy (Morse code).
Later, as modulation made it possible to transmit voices and music via wireless, the medium came to be called radio. With the advent of television, fax, data communication and the effective use of a larger portion of the spectrum, the term "wireless" has been resurrected.
Wireless technology is rapidly evolving and playing an increasing role in the lives of people throughout the world. Various technologies and devices are being developed in response to the growing use of wireless. In addition, larger numbers of people are relying on the technology directly or indirectly.
Wireless access technologies are commonly divided into categories, based on speed and distance.
- Wireless Personal Area Network (WPAN) technologies are designed to reach only about 10 meters. IrDA and Bluetooth are two common WPAN examples. Emerging technologies in this space include 802.15.4a (Zigbee) and 802.15.3c (UWB).
- Wireless Local Area Network (WLAN) technologies can deliver up to 200 Mbps at distances up to 100 meters. 802.11a/b/g (Wi-Fi) are widely deployed WLAN examples. Proprietary MIMO products and the new 802.11n high-speed WLAN standard are emerging technologies in this category.
- Wireless Metropolitan Area Network (WMAN) technologies deliver up to 75 Mbps over wireless "first mile" links that span several kilometers. There have been several iterations of the 802.16 Broadband Wireless Access WMAN standard, certified under the brand WiMAX. Fixed WiMAX is now being complemented by the emerging 802.20 Mobile WiMAX standard.
- Wireless Wide Area Network (WWAN) technologies now deliver up to a few hundred Kbps over large service areas such as cities, regions or even countries. Commonly deployed WWAN technologies include GSM/GPRS/EDGE and CDMA2000 1xRTT. These services are gradually being complemented by newer third-generation technologies like UMTS/HSDPA and CDMA EV-DO Rev.0/A. Future technologies here include HSUPA and EV-DO Rec.C.
A wireless LAN (WLAN) is one in which a mobile user can connect to a local area network (LAN) through a wireless (radio) connection. A wireless personal area network (WPAN) is a personal area network for interconnecting devices centered around a person's workspace in which the connections are wireless. Though IrDA and Bluetooth are quite advanced, WPAN technology continues to develop rapidly.
More on wireless mesh networks
Wireless mesh networks are a growing trend. To learn more about them, listen to this Whatis.com podcast "What are wireless mesh networks?"
Protocols and specifications
Wi-Fi is a term for certain types of WLAN that use specifications in the 802.11 family. The term Wi-Fi was created by an organization called the Wi-Fi Alliance, which oversees tests that certify product interoperability. A wireless LAN node that provides a public Internet connection via Wi-Fi from a given location is called a hot spot. Many airports, hotels, and fast-food facilities offer public access to Wi-Fi networks.
A wireless industry coalition, WiMAX (Worldwide Interoperability for Microwave Access), organized to advance IEEE 802.16 standards for wireless broadband access, sometimes referred to as BWA, networks. WiMax has a range of up to 30 miles, presenting provider networks with a viable wireless last-mile solution.
Bluetooth is a telecommunications industry specification that describes how mobile phones, computers and personal digital assistants (PDAs) can be easily interconnected using a short-range wireless connection.
Ultra wideband (also known as UWB or digital pulse wireless) is a wireless technology for transmitting large amounts of digital data over a wide spectrum of frequency bands with very low power for a short distance (up to 230 feet) and carrying signals through doors and other obstacles that tend to reflect signals at more limited bandwidths and a higher power.
WAP (Wireless Application Protocol) is a specification for a set of communication protocols to standardize the way that wireless devices can be used for Internet access. Designed to provide a WLAN with a level of security and privacy comparable to what is usually expected of a wired LAN, Wired Equivalent Privacy (WEP) is a security protocol, specified in the IEEE Wi-Fi standard, 802.11. Another security standard for users of computers equipped with Wi-Fi wireless connection is Wi-Fi Protected Access (WPA). It is an improvement on, and is expected to replace, the original Wi-Fi security standard, WEP.
802.11 is an evolving family of specifications for WLANs developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE). There are several specifications in the family, and new ones are occasionally added.
Specifications that have not yet been formally approved or deployed, 802.11x refers to a group of evolving WLAN standards that are under development as elements of the IEEE 802.11 family of specifications. The 802.11 specifications are summarized in our 802.11 Fast Reference, which includes a link to our definition of each specification.
More on Wi-Fi and WiMa
Read a more detailed explanation of the difference between Wi-Fi and WiMAX to better understand how these technologies are related and how they will further the future of wireless.