The 5 Ws of WiMAX

What

Though fixed wireless technology is not new, a major interoperability standard, Wireless Interoperability for Microwave Access (WiMAX), is relatively new in North America. WiMAX lets base stations, customer premise equipment and modem cards manufactured by different vendors operate on the same network. It is based on some of the 802.16 standards stipulated by the Institute of Electrical and Electronics Engineers (IEEE) Wireless Municipal Area Networks Working Group for Broadband Wireless Access.

The Fixed WiMAX standard is based on IEEE 802.16 2004, while Mobile WiMAX is based on the IEEE 802.16e-2005 standard.

The WiMAX Forum, which certifies products for interoperability, says it has “developed profiles” for the 2.3, 2.5 and 3.5 GHz frequency ranges.

Although it has been compared to Wi-Fi, the capabilities are much different. Whereas Wi-Fi has a range of 100 metres and requires line of sight, WiMAX is intended to provide coverage at much greater ranges, without the requirement for line of sight, making it better suited for municipal networks and as an access technology for telecommunications carriers. The exact range depends on factors such as interference from buildings and terrain.

Products certified by the WiMAX Forum are supposed to provide a range of up to 5 km.

“We have seen (ranges) in excess of 10 km but I don’t think you’ll get much more than 10 or 15, honestly,” said Ted Chislett, president of Primus Telecommunications Canada Inc. which is conducting trials in Hamilton and suburban Toronto. “As you get further out, you’ll get slower speeds.”

Like Wi-Fi, WiMAX is designed to provide broadband connections. The WiMAX Forum, which tests equipment for interoperability, states “certified systems can be expected to deliver capacity of up to 40 Mbps per channel.”

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But individual users won’t get this much bandwidth, said Monica Paolini, president of Senza Fili Consulting LLC of Sammamish, Wash.

“It will be split among the users that happen to be in the coverage area of the sector,” she said.

On its Web site, Primus says its trial service can provide up to 1 Megabits pers second (Mbps) downstream and 128 Kilobits per second (Kbps) upstream. But Chislett says he hopes users can get much more.

“I would hope that we could get a couple of (Mbps) down and almost (1 Mbps) up,” he said.

Who

The 802.16 standards are actually written by the IEEE, not the WiMAX Forum. The WiMAX Forum certifies the products and defines system profiles. A piece of equipment that is certified by the WiMAX Forum means it complies with IEEE 802.16 and is interoperable with equipment from other vendors that are WiMAX Forum-Certified.

One WiMAX Forum member is Intel Corp., which makes microprocessors designed to allow notebook PCs to support Mobile WiMAX, and currently supports service in the 2.5 GHz spectrum. The chip maker recently announced it will support other frequency ranges, though it’s unclear which ranges and when.

Meanwhile, Canada is home to several vendors that make base stations and customer premise equipment.

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SR Telecom of Montreal, for example, sells a lot of its WiMAX equipment overseas to carriers in places like Cameroon, Mexico and the Philippines.

Redline Communications Inc. of Markham, Ont. manufacture base stations and customer premise equipment and has sold equipment in 50 countries.

One of the best known providers is Clearwire Corp., which recently announced plans to merge with Sprint Nextel to invest US$3.2 billion into a national WiMAX network for American cities.

Clearwire offers download speeds of up to 2 Mbps and upload speeds of up to 256 Kbps using non line of sight orthogonal frequency division multiplexing technology. It has licences for 2.5 GHz spectrum and offers both voice and data, and its equipment includes the towers, plus routers and modems (which function as antennas) for customers. Clearwire also provides the ClearPlugs Ethernet Wall Mount Module, which allows the signal to travel over power cables.

Clearwire’s service will give a good indication of how good WiMAX equipment is at traffic shaping and providing quality of service, said Lisa Pierce, vice-president and principal analyst at Cambridge, Mass.-based Forrester Research Inc.

“If we take a look at the underlying technology there have been issues with scalability,” she said. “This is why what Sprint and Clearwire are doing is so important. It will tell us a lot about it.”

Primus is also closely watching Clearwire’s development, Chislett said. Primus Canada’s trial service currently uses 3.5 GHz spectrum owned by MIPPS Inc. Where up until now, most installations have taken place outside of North America, which is where SR Telecom and Redline have sold most of their gear. Most installations in North America will be fixed, not mobile, said Pierce.

“Some pre-WiMAX is mobile but it’s a very very small percentage of connections out there, certainly under one per cent” in the U.S., she said. “In certain countries overseas where landline infrastructure is scarce, WiMAX can be used quite extensively.”

One of Redline’s customers is Sify Technologies Ltd., which provides service in India, serving consumers, banks, retailers and manufacturers.

Suitor said in the developed world, he expects a surge in the percentage of people using WiMAX as a broadband access technology.

“It’s a technology that has really begun to hit its stride,” Suitor said. “We expect that in developed markets, WiMAX will move from not on the radar screen to having 10 to 20 per cent market share (of total broadband access circuits, including DSL and cable) over the next couple of years, as an access technology.”

A Redline customer in North America is One Ring Networks of Atlanta, which is building a WiMAX network to cover the city. Paolini said the market right now for WiMAX in North America is small and mostly residential, though applications for specific industries (such as mining, transportation, health care and security) or municipal services, may be carried over WiMAX networks.

‘For example, she said, it could be used to connect police cars to their stations. “If you have security cameras, they need to be connected,” Paolini said. And Pierce said she recently spoke with a user in the oil industry who said they may use it to connect networks between adjacent oil fields.

“It has some characteristics that could be very good for private applications,” Pierce said. “If you’re using a different piece of the spectrum it is possible to do it yourself as opposed to buying a service but in a traditional campus environment we see it more as an augmentation of a wireless LAN infrastructure than as a replacement for it.”

When

In Canada, the rollout has been slower due to the emphasis on development for the 2.5 GHz frequency ranges. Chislett said he keeps having to push back Primus’s rollout, which is why the company is only offering service to trial users right now in the 3.5 GHz range, using prototype equipment from manufacturers including Alcatel-Lucent and Motorola.

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“It’s probably going to be into 2009 before we’re at a stage where we think we may be able to go to something which is a productized version out there,” he said. “It seems to me like every quarter I’m extending it another quarter.”

Manufacturers are concentrating more on 2.5GHz equipment because that’s the frequency Clearwire is operating in, he said.

Why

One reason users may prefer WiMAX is its quality of service, Paolini said. “Up until now, with 3G networks and video, and HSPA, all connections are best effort, so you either get a connection or not,” she said. “With WiMAX and LTE as well, you can have quality of service and you can manage traffic in a more fine-grain way. You can decide which applications have priority, you can create virtual networks that have a specific allocated bandwidth.”

According to the WiMAX Forum, the technology is 2.5 times faster than high speed downlink packet access (HSDPA), a third-generation service available from many GSM carriers. The WiMAX Forum says because WiMAX is designed for data rather than voice, you can increase bandwidth without affecting voice quality. But even if a WiMAX network does carry voice, it can ensure quality of service, Suitor said.

Redline’s technology gives five different service levels, and One Ring gives business customers “multiple voice circuits concurrently over top of the WiMAX transport with full quality of service,” Suitor said. WiMAX can also be cheaper, Paolini said.

“A lot of applications are currently not supported by cellular operators because it’s not sufficiently profitable for them and they don’t have the capacity,” she said. “If you’re a cellular operator your cost per megabyte is higher.”

Pierce said in the U.S., it can take 45 business days, with some carriers, to get a T1 line, and many users are not happy with the incumbent carriers. “I see great opportunity to use fixed WiMAX as ultimately a replacement for T1 connections,” Pierce said. “The price of T1 connections in the United States is going up, and the reliability is not everything you would expect it to be.”

Chislett offers other reasons why mid-sized companies may want WiMAX. “It’s so easy to deploy and throw it in quickly,” he said. “It’s a great disaster recovery (technology).”