Information from
Johnson Consulting

  1. What is "Bluetooth"?

  2. How could Bluetooth be used?

  3. Basic Bluetooth functions

  4. How does Bluetooth work?

  5. Establishing network connections

  6. What kind of traffic can Bluetooth handle?

  7. What about competing technologies?

  8. What about radiation; is it dangerous?

  9. What is Bluetooth´s growth potential?

  10. What is Bluetooth´s prestanda?

  11. What about Bluetooth´s security?

  12. Bluetooth definitions

  13. How networks are formed and controlled

  14. What´s the advantage of frequency-hopping?

  15. How timeslots are used

Bluetooth - An Overview

What about competing technologies?

Is Bluetooth a Wireless LAN (WLAN)?

No, Bluetooth is not intended as a wireless extension of ordinary LANs. Both Bluetooth and WLANs are based upon the IEEE 802.11-standard. But there are too many differences for these systems to replace each others:
  • WLANs are essentially ordinary LAN-protocols modulated on carrier waves. Bluetooth is more complex than that.
  • Bluetooth´s essence is dynamically configured units. That´s not how LANs work.
  • Bluetooth hops very fast (1600 hops/second) between frequencies, which does not allow for long datablocks. A Bluetooth channel cannot handle as high data throughput as a WLAN.
  • Bluetooth relies on ad-hoc-connectivity. This does not square well with (predominantly) server-based LANs.
Moreover, when a Bluetooth connection collides with a wireless LAN connection, either or both connections can jam! Bluetooth may be a boon to mobile devices, but to wireless LANs, it's a bully!!

The problem: It uses the 2.4 GHz radio frequency, the same used by wireless LANs based on the IEEE 802.11 standard. But these two technologies have different functions. Bluetooth requires little power and is meant for transmitting small amounts of data (at 1Mbps) over short distances (up to 10 meters). 802.11 connections can range in transmission rates from 2 Mbps to 11 Mbps and at distances from 15 to about 100 meters.

Why not equip laptop PCs with mobile phone units?

Cost is too high. There are many different phone standards to choose from. There is no standard that is universally available around the world. The usage model for mobile PCs do not match that of phones.

Why not use contactless "smart" cards?

Well; yes and no. Contactless "smart" cards are the basis of some Bluetooth-applications. But Bluetooth goes much further than that. Smart cards:
  • are point-to-point
  • are not session-oriented
  • have no inherent reliability when transmitting/receiving information. They are better compared with the contactless transmission-mode on the Internet.
All the functionality that ”smart cards” have can be included in Bluetooth´s functionality.

Could not WAP be used?

”WAP - Wireless Application Protocol - is a framework specified by industry leaders supporting mobile IT-solutions”. It is a communications protocol for mobile phones, meant as an extension of available, Internet-based services. WAP only covers the higher protocol levels. There is no connection to the 802.11 standard.

WAP might not survive for long; Japan has a corresponding service that is far more extensive.

How about Infrared technology?

One of the 3 IrDa-standards that are used today is called ”IrDa-Data”, and this standard is primarily meant for data transmission. But the main differences as compared to Bluetooth are:
  • IrDa is not omnidirectional, as is Bluetooth. The IrDa-beam has to be aimed at the receiving antenna.
  • IrDa must hav a free line of sight.
  • IrDa is point-to-point; only 2 units at a time can communicate.
For a good comparison of these 2 technologies, visit the Counterpoint website.

However, new technology from an Israeli company could free users from having to line up the infra-red ports on their portables in order to exchange data. Infra-Com has launched infra-red technology which allows links without the communicating devices having to 'see' each other in the traditional line-of-sight way.

The line-of-sight requirement has been the impetus for challenging wireless technologies such as Bluetooth. But Infra-Com's new Red Beamer technology for portable devices uses indirect and diffused infra-red light, working rather like a light bulb, with light bouncing off walls and ceilings to reach the device target.

Initially, devices receiving Red Beamer will need an external infra-red peripheral for data to be exchanged, but Infra-Com intends to embed the technology into devices' PCI cards. But Red Beamer's initial 56 kbps transmission speed is much slower than Bluetooth's target of 2mbps.

So there you are; Bluetooth is simply the best!


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Last Updated: 2004-04-17
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