Bluetooth Battles a Red Eye

Bluetooth's strange relationship with Infrared Data Association (IrDA) technology continues to raise eyebrows and questions. Was Bluetooth developed as a replacement for IrDA? Or are the two meant to be complementary?

Bluetooth developers say they did not set out solely to create an alternative to IrDA.

Infrared limitation was one driving force behind the development of Bluetooth, said Skip Bryan, Ericsson director of technology marketing, U.S. division. However, low cost, small volume and low power were other reasons.

Bluetooth's 1-to-many capability is an enhancement over the 1-to-1 limitation of IrDA technology. But that same advantage also can complicate some application scenarios that infrared handles more simply.

"Bluetooth is a little more complex than the point and shoot of infrared," Bryan said while conceeding that IrDA has a higher data rate, so it handles 1-to-1 data connections better.

Bluetooth's slower pace is obvious in several applications. For instance, if you want to do a 1-to-1 business-card exchange in a room full of people, Bluetooth might see several devices with the opportunity to do the exchange. It then has to determine which device is the "right" one.

Bryan said the time lapse can be nominal, and the technology's effectiveness is not compromised by the delay.

Don Baumgartner, Extended Systems division manager for mobile solutions division, disagrees.

"Bluetooth has been struggling with the recognition problem for some time," Baumgartner said. "Say, for example, that Bluetooth didn't know the address of the device it wished to connect with. It would have the added steps of going through a list of PINs, doing a discovery on each one, then asking the device it wished to connect with to identify itself from the list."

Despite its questionable advantage in certain applications, Bluetooth is slated to carve out a niche for itself in both the public and private sectors.

"The private use would be the devices a user sets up individually -- 'my' devices," Bryan said. For instance, a user might have "my" printer, "my" laptop, "my" PC, "my" personal digital assistant (PDA) and "my" wireless phone.

Anytime those devices are present in proximity to each other, they would automatically connect and do whatever the software they've been set up with is designed to do.

Public situations add a step in the connectivity process because the user has to review the potential connection devices first, then select one before the connection can be initialized. This process secures the connection through layers of authentication and encryption.

However, Skip Powers, Silicon Wave director of corporate division, believes it is convenience, not security, that will be the key issue in Bluetooth's acceptance or rejection by the consumer.

"If you look at the hassle factor, infrared is at a disadvantage to Bluetooth," Powers said. "With infrared, you have to align the two devices critically."

Baumgartner agrees that Blue-tooth is superior to IrDA in applications that require hidden connections.

Bluetooth's advantage lies in its pairing capability. For devices that are frequently paired, Bluetooth allows for rapid, worry-free connectivity -- whether it's phones and headsets, PDAs and printers, or car doors and key rings.

That's why IrDA companies such as Extended Systems are joining the ranks of the of the Bluetooth initiative.