The emerging IEEE 802.16 standard, commonly known as WiMAX, promises to deliver last mile wireless broadband internet access capable of carrying data intensive applications, such as VoIP and streaming video, to Metropolitan Area Networks, as well as sub-urban and rural communities. WiMAX is considered a disruptive technology, designed as an alternative to fixed line DSL and coaxial technologies, and with its 802.16e revision, the cell phone networks as well.
Worldwide Interoperability for Microwave AXcess will operate over licensed and non licensed frequencies using non line of sight (NLOS) and line of sight technologies, extending broadband coverage to cities and towns wirelessly via a metro area network. Additionaly, because of its far reaching capabilities and ease of implementation, wimax is the one technology likey to bridge the Digital Divide, connecting underdeveloped regions and sparsely populated rural areas much more cost effectively than deploying a wireline infrastructure.
WiMAX and WiFi Compared
The widespread adoption of the wireless LAN in the business community, as well as the emergence of WiFi hotspots in public areas, airports, hotels and cafes, has been of tremendous significance in providing mobility to business people and consumers alike. Thanks to the open standards guided by the 802.11 committee and the WiFi Alliance, WiFi technology is becoming ingrained in our society. WiMAX plans to take WiFi a step further.
While the two technologies may sound the same, they are from their conception designed for totally different applications. WiFi is a short range standard that was designed primarily as an extension of the local area network (LAN) to provide mobility for the end user. It operates over unlicensed frequencies and has a range of about 100 meters, depending on obstructions. Typically one access point will be connected to a fixed line network, either a wired LAN or a DSL/cable broadband connection, and the range can be extended by adding more access points at appropriate distances.
WiMAX, on the other hand, is designed to function as a carrier network, or a wireless Internet service provider (WISP), blanketing whole cities and regions with broadband Internet access comparable to DSL. Coverage in optimal conditions could reach 50 kilometers, but in reality are more like 5 km for users with NLOS customer premise equipment (CPE), or up to 15 km with a CPE connected to an external line of sight antenna.
As the older more established technology, the 802.11 WiFi has been used in a mesh topology to cover larger areas such as college campuses and municipalities, for example to connect the terminals in police vehicles to their database. The emerging 802.16 WiMAX will be better suited for larger deployments, and will in fact compliment the private WiFi networks by offering a cheaper and more secure Internet access for data and voice applications.
The WiMAX Standards: Fixed, Nomadic, and Mobile
The 802.16 standard developed by the IEEE envisions a fixed wireless broadband network operating in the spectrum range of 10 GHz to 66 GHz. Originally, only the licensed spectrum was addressed in this range, and line-of-sight multipath technology was dealt with by adopting OFDM as the standard. Subsequent revisions added the 2 GHz to 11 GHz band to the spectrum, and incorporated support for non-line-of-sight technologies and Quality of Service (QoS) techniques, a prerequisite for such time sensitive applications as voice and video.
The revision known as 802.16-2004(d) rolled up all the previous revisions and then added some. Most of these original issues dealt with the Physical and Media Access Control layers, and resulted in a standards list of optional and mandatory elements by which vendors could design their products.
The resulting fixed WiMAX standard has a data rate of up to 40 Mbps, support for half and full duplex transmission, improved QoS, and the incorporation of multiple polling techniques, ultimately reducing packet collisions and overhead.
Base stations are to support several different topologies, such as wireline backhauling, microwave point to point connections, and the ability for the WiMAX base station to backhaul itself by reserving a part of the bandwidth for that purpose.
By design, 802.16d would cater to the residential and small business markets offering wireless broadband access with speeds comparable to DSL. Enterprise markets could be served at T1/E1 data rates.
While this version of WiMax is called fixed, it is in all actuality nomadic. Users on a private WiFi network indoors could be passed off seamlessly to the publicWiMAX network when moving outdoors, their hardware determining the best network available. Devices on the WiMAX data network would include laptops, PDAs, and smart phones equipped with an on board WiMAX capable chip or PC card, utilizing the spectrum for voice, data, video, and music transfers.
Nomadic WiMAX provides for limited mobility in that the range of coverage is handled by the same base station.
WiMAX Goes Mobile
With the adoption of the 802.16e revision in late 2005, all the hype has been on Mobile WiMAX, a technology designed to compete with the cellular networks.
With major support from manufacturers like Intel, Motorola, Siemens, and Nokia among others, mobile WiMAX is built on open standards and is purported to be 4 times faster than the cellular 3G technologies (EVDO, HSDPA). Significant cost savings can be achieved for voice applications by placing calls over the Internet through VoIP.
802.16e provides for fast and seamless handoffs between base stations, with a cell radius of about 3 miles, similar to cellular networks. The standard was ratified in late 2005, and real world applications are beginning to show up in 2007, with more robust development expected throughout 2008.
Because this technology is such a threat to the legacy telecommunications industry, it is no surprise that Sprint Nextel will be deploying WiMAX as opposed to EVDO in its 4G network. Sprint has been buying up much of the WiMAX spectrum, and has recently announced a partnership with Nokia to deploy WiMAX to four Texas cities by mid 2008. This is not their first WiMAX network, and telcos around the globe have been doing the same.
The 802.16 standards are a work in progress, and as such, are subject to changes and revisions. As the standards committee works on the technology, the WiMAX Forum hopes to do what the WiFi Alliance did for the 802.11 standards, by promoting interoperability between components through testing, and offering WiMAX certification to vendors that conform to the 802.16 standards.
It should be noted that many of the WiMAX implementations at the time of this writing are proprietary, and thus do not necessarily follow the recommendations of the IEEE or the WiMAX Forum. The broadband wireless ISP Clearwire Communications has over 200,000 subscribers in 375 cites, and calls its service a WiMAX-class solution, utilizing next-generation, non-line-of-sight wireless technology. Other early adopters of pre-WiMAX technology are forging ahead, providing wireless broadband access to residential consumers and the small business market, with many companies climbing aboard the evolving standards bandwagon to assure interoperability and backwards compatibility of devices and applications.
Author: Michael Talbert
Article Source: EzineArticles.com
Provided by: Canada duty
- Save Our Community Broadband Wireless Spectrum
- Volunteer in Panama
- Computer Instructor and Network guru
Related Posts -
Phone System for Small Business - Is VOIP Worth It? Get the Pro's and Con's Whether youre at the office or watching the television, it is hard not to hear about the new telecommunications system, voice over internet provider (VoIP). This emerging telephone system allows for major savings, to both residential and business phone users, due to phone calls being routed over the Internet....... - Technology Help Small to Mid Size Companies Achieve Their Financial Goals Today, IT solutions are aiding small and mid-sized companies alike, as they compete with Fortune 500 companies for a piece of the pie. We live in an age of fierce competitiveness, fiscal concern, and global turmoil and uncertainty. Companies are working hard to continually improve operational efficiency. Many are......
- VegaStream - VoIP & Emergency Services VoIP and Geographic LocationThe emergency services have come to rely on certain features of the traditional telephone system to enable them to do their jobs and to safeguard against misuse of the general public's privilege to call them night or day. The key feature is the Caller Line Indication......
- Wireless Broadband and IP Telephony The advent of wireless broadband has put a new twist on people's mobility and communications. Wireless broadband connections can take many different forms. From an extension of conventional wired networks in your home or office, to wireless coverage of entire metropolitan areas, to the proliferation of WiFi hotspots all......
- DECT 6.0 Cordless Phone - The Standard For the Best Cordless Phones How do you compare cordless phones? Do you buy the cheapest, sleekest or the one with the most features. Are you confused by cordless phone technology and cordless phone frequencies? What is a DECT 6.0 cordless phone and which is the best frequency: 900 MHz, 1.9 GHz, 2.4 GHz......
Related Websites -
Save Money and Make Your Xbox 360 Wireless for $20 This is part of a 3 post series which I will dedicate to saving money by spending money on technology. I consider my blog a personal finance blog with a fusion of many areas of interest that promote good finances, learning, and happiness. I hope these posts are not too...... -
Home Network Security [/caption] Home Computer security 1. What is computer security? Computer security is the process of preventing and detecting unauthorized use of your computer. Prevention measures help you to stop unauthorized users (also known as "intruders") from accessing any part of your computer system. Detection helps you to determine whether or...... -
Effective Advertising Using Ezine Solo Ads So many people talk about advertising and marketing when it comes to your network marketing internet business. You have probably heard of forum marketing, article marketing, and even the importance of using Pay-Per-Click marketing. These are all very effective marketing strategies but there is another great way to get...... -
Gators Football Roster 2009 Roster Football Player Bios Coaching Staff Urban Meyer - Head Coach - 4 years at UF Steve Addazio - Offensive Coordinator/Offensive Line - 4 years Vance Bedford - Cornerbacks - 1 years Kenny Carter - Running Backs - 1 years Billy Gonzales - Recruiting Coordinator/Wide Receivers - 4 years...... - The Information Technology Opening New Prospects There has come time when each interested person can is easy become the owner of high-speed access to the Internet at home and not only. Epoch of Dial-up finishes the existence. To it on change comes the century of the Information technology opening new prospects and changing the relation of......
Related posts:
