Infrared meets speed and security needs

Bluetooth and its ilk may be making the news, but there is an alternative, and in the battle for wireless networks the...

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Bluetooth and its ilk may be making the news, but there is an alternative, and in the battle for wireless networks the short-range option may prove to be the victor



You would be forgiven for believing that infrared data connectivity has been sidelined by the arrival of radio frequency wireless Lan standards-based equipment, which has enjoyed phenomenal exponential growth in recent years. But with more than 500 million infrared interfaces shipping each year, it clearly dwarfs WLan in the volume race.

And don't assume that this market is sustained by remote- control units, for nearly half of the interfaces shipped conform to the Infrared Data Association (IRDA) standard, which clearly targets data communication.

Famously associated with applications such as personal digital assistant to laptop synchronisation, PDA business card exchange and short-haul mobile phone data transfer; IRDA, with its short range and relatively low 4mbps throughput, was understandably discounted by the IT community as irrelevant for WLan application.

Infrared has squared up to recent competition from Bluetooth, an alternative radio frequency communications standard designed to support similar connectivity to IRDA. Simple set-up and good reliability initially secured IRDA's popularity over Bluetooth. More recently, questions about Bluetooth's inherent insecurity have reinforced IRDA's popularity.

IRDA, with its range limit of 1m and inability to penetrate walls, is extremely secure. Bluetooth, on the other hand, is mired in controversy, with numerous hacking stories and reminders to users to disable it when not in use. But really, the battle with Bluetooth is small beer in comparison with the prize of ubiquitous connectivity on which IRDA is focused.

IRDA is on the move, with activity and initiatives that are likely to further increase the already significant number of unit shipments. Moreover, emerging applications will cause pause for thought and re-evaluation of infrared and its benefits for widespread data communications uses.

This even applies to WLan, particularly where security is paramount or third-party interference is affecting the user experience.

The infrared supplier community has embraced the challenge to deliver data rates in excess of 100mbps, with talk of possibly achieving 500mbps to accommodate a wide range of imaginative applications for which real demand has already been identified in Japan and the Far East.

Two immediate applications that are set to transform our lives are multimedia file transfers and Electronic Funds Transfer at the point of sale.

Fast-connect methods allow near instant exchange of high-definition photos between digital cameras, phones, PDAs and, potentially, television sets over infrared transmissions. An interface to television sets of the future will enable home users to simply view their photo albums through their TV where the whole family can gather round.

Next generation multimedia file transfer will be more demanding of technology than traditional Jpeg photos or short audio files and ring tones.

In the near future consumers will be able to download video films from kiosks, which are already being designed and built and will soon be installed at stores, railway stations and airports. The video rental industry is preparing for change far more significant than the recent migration from video tape to DVD.

The concept is simple. Before embarking upon a journey the consumer downloads a film to their phone or PDA for viewing en route. Both radio frequency WLan and Bluetooth are inappropriate vehicles, since it would not take long for people to work out how to share a single download.

Infrared, on the other hand, cannot permeate walls or physical barriers and, with the IRDA specification limiting range to 1m, it is ideal for this application. Of course the size of the files in question renders a throughput of 4mbps or 16mbps inadequate, but with potential data rates exceeding 100mbps in the relatively near future IRDA is set to offer sufficient performance to satisfy users rushing for planes and trains. In making a quantum leap in data rates, IRDA has not forgotten the mantra of low power consumption, essential for portable equipment, and another area in which it scores over radio frequency WLan.

It is not unreasonable to assume that the same application will migrate to set-top TV boxes where a home user will be able to point a phone or PDA and upload a film for viewing later. When combined with the digital wallet of the future the commercial opportunities are immense.

For this vision to become reality it will be necessary for IRDA to review its commitment to short range, but there are pressures to do so from a variety of sources.

The mobile phone is fast becoming a digital wallet. If you browse the menu of a modern device, you will see options to store credit card details. At first glance this would appear to be a useful data back-up. However, trials already under way in Japan point to a more functional objective.

Currently you carry a wad of credit cards with magnetic stripes and intelligent chips, storing information that allows you to purchase goods and services. In addition to your credit/debit card details, other information that could easily be stored on your phone might include passes for public transport, discount tokens and awards/loyalty points.

At the point of sale, you will point and shoot your digital wallet to an Epos terminal, a vending machine, car parking barrier, railway station access gate etc, to pay.

There are strong return on investment arguments to support the business case. Retailers are excited by the opportunity to speed up transactions at the point of sale and, along with the banking fraternity, see obvious benefits in digital receipts that will be issued to your phone as opposed to the paper-based, easily misplaced alternative.

From a consumer standpoint, ease of use (imagine never having to queue for a train or bus ticket) coupled with the potential personal money management programs that will doubtless accompany the technology, make the proposition equally attractive.

IRDA has a special interest group targeting this initiative. The group is already in collusion with other standards bodies, including retail and banking consortia to ensure a universal, dependable and secure service.

With security clearly paramount, IRDA wins out as the obvious communications medium with its high speed, low distance and limited field of view, coupled with a low power consumption rate. IRDA has obvious security attractions that cannot be matched by WLan or Bluetooth.

Considerable work has been completed by the infrared financial messaging group and trials are under way. Commercially available RS232 to IRDA adaptors ensure low-cost easy upgrade of existing Epos terminals and vending equipment.

For sceptics concerned about the ramifications of having a phone stolen it is worth noting that the pilot projects are largely taking place in Japan, where the 40 million strong mobile phone user base is less concerned about phone theft. In any event, it is arguably much easier for credit to be abused with card-based systems than it will be with a digital wallet.

A number of emerging applications are likely to move IRDA to endorse a variety of standards in much the same way that the IEEE concerns itself with multiple media for data communications.

A practical TV-based photo album, for example, is likely to see consumers demanding communications distances greater than 1m to allow the family to sit around the living room for the show.

Pointing and uploading Powerpoint slides one at a time to projectors will doubtless need to afford the presenter an opportunity to move around a stage at will, once again giving cause for reviewing extensions to the 1m limit.

An application that has been presented to IRDA supporting distances of 300m or more is already being embraced by highways agencies in Korea, Europe and the US that are seeking low-cost dependable methods for collecting motorway tolls.

To date, radio frequency products have dominated this market, but there are attractions to infrared. The lower cost of communications components is not lost on agencies or consumers.

Equally important is modern infrared technology's tolerance to third-party interference, notably metallic elements in windscreens, which have the propensity to block radio frequency communication. Add your electronic wallet and it becomes clear that infrared should be actively considered for longer-range communications, which leads to the potential for a WLan architecture based on infrared.

About six years ago, I extolled the virtue of infrared WLan at an international press symposium, only to be largely dismissed by a community naturally excited by the success of emerging radio frequency standards. But with the throughput achievements that I predicted at the time now becoming a reality, it begs the question what advantages infrared WLan could bring over radio frequency alternatives.

Radio frequency WLans are not utopian. There is third-party interference from microwave ovens, Dect phones and Bluetooth devices. There are security concerns surrounding an inability to trap radio waves within a building, and there are spectrum planning challenges coming to the fore as we begin to saturate the airwaves.

Infrared cannot penetrate walls, and this gives a high degree of control over data leakage. It is not subject to spectrum restrictions, as is the case with radio frequency communications, alleviating much of the potential radio planning hassle.

Until now data rates, range and field of view limitations have made IRDA-based technology unsuitable for WLan applications. But with the prospect of these issues being addressed in a standards-compliant manner there is a distinct possibility that low-cost infrared products will emerge, where it will have particular appeal in certain environments.

Within military and other high security environs, high-speed infrared WLan offers ease of secure implementation.

In hospitals, aircraft and other applications where third-party equipment is sensitive to radio frequency interference, an infrared WLan can be safely and easily deployed.

And who knows, once infrared WLan equipment becomes commercially available it is not inconceivable that the low-cost arch- itecture of the communications system may make the apparently collapsed prices of radio frequency WLan equipment today seem outrageously expensive.

John Earley is general manager at wireless research firm Supergold


What is IRDA and what is it for?

The Infrared Data Association is a membership-based organisation.

It was founded in 1993 and is dedicated to developing standards for wireless, infrared transmission systems between computers.

IRDA ports fitted to a laptop or personal digital assistant can exchange data with a desktop computer or use a printer without a cable connection.

Just as a TV remote control requires line-of-sight access, IRDA transmissions are restricted by obstacles and walls, which can be a security benefit.

The IRDA serial infrared physical layer provides a half-duplex connection of up to 115.2kbps. At this speed a low-cost chip can be used, although more expensive, high-speed extensions up to 4mbps for fast infrared have also been defined.

To enable the simultaneous handshaking and multiplexing of several different data streams IRDA uses the infrared link access protocol and the infrared link management protocol.

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