By WALTER S. MOSSBERG May 15, 2008
Wireless cellphone earpieces can make people look faintly ridiculous as they stroll down the street or around the office, seemingly talking to themselves with ugly appendages sprouting from their heads. The pulsing blue lights on these things can make people look like robots. And these battery-powered gadgets, which use a power-hungry wireless technology called Bluetooth, are just one more thing to charge.
But such headsets are becoming more necessary, at least in the car. A growing number of cities and states are requiring all calls made while driving be conducted in a "hands-free" manner. Two more big states, California and Washington, will begin enforcing such laws in July. Unless drivers in these places have cars with costly built-in Bluetooth speakers and microphones, many will turn to wireless earpieces to make calls legally.
Now, two of the most important wireless earpiece makers are bringing out new models that attempt to make their products more attractive and functional. One is a new version of the Jawbone, which has become a leader in the high-priced end of the market. The other is a new model from Plantronics, which vies with Motorola as the top seller of wireless earpieces.
I've been testing both the new $130 Jawbone, and the $150 Plantronics Discovery 925, and both work well, despite some drawbacks. Each worked properly with both an inexpensive Motorola Razr phone from Verizon and a sophisticated Apple iPhone from AT&T. But I preferred the Jawbone, because of its technology and design.
The new Jawbone, made by a closely held San Francisco company called Aliph, is 50% smaller than the original Jawbone, which I reviewed in 2006. It continues to boast the original Jawbone's signature feature: a remarkable ability to suppress background noise and isolate the wearer's voice.
Jawbone performs this feat by using a sensor that touches your skin lightly to identify your voice through the vibration of the bones in your face. Using this information, its microphone can more easily distinguish your voice from background noise, and accurately suppress the latter.
This feature, originally called "Noise Shield" and now theatrically renamed "Noise Assassin," really works. When the company first showed off the original Jawbone, it made live calls standing in front of things like weed whackers and boom boxes, and then turned the bone-sensing feature on and off to show the dramatic difference.
In my tests of the new, much smaller Jawbone, I stood a few feet from a roaring vacuum cleaner, while on a phone call. The person I was calling could barely hear me with Noise Assassin turned off, but could clearly make me out when I turned it on.
By contrast, the Plantronics Discovery failed my noise test. It was useless anywhere near the vacuum cleaner. This was obviously an extreme case, but it served as a stand-in for other loud noises likely to be encountered in real life, like large trucks, or construction gear on the streets.
The biggest flaw in the original Jawbone, in my 2006 tests, was its performance in wind, which was poor. The Jawbone did much better in my latest tests. During a Jawbone call from a car with all the windows down and the sunroof open, my voice was easy to make out, according to the person I was calling. The new Plantronics earpiece did just as well in this wind test.
Plantronics claims its headset also enhances the voice of the person you are calling, a claim Aliph doesn't make for the Jawbone. But, while voices sounded fine on the Plantronics, I couldn't detect any difference between the two on that score.
Both gadgets are meant to be more stylish, and both will be available in multiple colors. But, while the Jawbone is just a smaller iteration of its original slab-like form, Plantronics has done something more radical with the Discovery 925: It has tried to make it look like jewelry. The Discovery's electronics are housed in the diamond-shaped portion of the device that goes on the ear, and the microphone sits at the end of a long, V-shaped boom that is open in the center. Plantronics says the design is suitable for both genders, but admits it is a bit more aimed at women and at fashion-conscious men.
I believe some men wouldn't feel comfortable wearing this new Plantronics model. It's also longer than the Jawbone. But I did find it more comfortable to wear, since it doesn't protrude as much into the ear.
The Plantronics claims longer talk time -- five hours vs. four hours for the Jawbone, but the Jawbone claims longer standby time -- eight days, vs. seven days for the Plantronics. The Jawbone weighs more, at 10 grams, compared with 8 grams for the Plantronics, but neither felt heavy on my ear.
I did prefer the Plantronics' controls over the Jawbone's. The former uses obvious buttons, while the latter employs unmarked, hidden buttons whose location you have to learn by touch.
Both of these earpieces do the job, but if you have to choose one, I'd pick the Jawbone.
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Low energy Bluetooth breaks cover
(Techworld.com)
Bluetooth's low-power variant could be everywhere starting next year, and other low-power networking options had better watch out, say the new standard's backers.
Last year, a Nokia technology called Wibree was adopted as a low-power variant of Bluetooth, by the SIG (special interest group) which directs the standard. The technology was demonstrated earlier this month under the "engineering name" ultra-low power (ULP) Bluetooth.
The technology is due for a new "marketing name", we hear. It's apparently going to become "Bluetooth low energy", and start to contend with rivals. It will be a tough contest, and the winner will be the one that is built into most devices, costs least to implement, and use least power - so devices' batteries will last longer.
Technology comparison
One technology that should look to its laurels is ZigBee, the low energy wireless mesh network that has been on its way to household appliances for the last five years. Bob Heile, chair of the ZigBee Alliance claims not to be worried by low-power Bluetooth: "I don't put them on the radar screen," he told Techworld. "It's just Bluetooth with frequency hopping turned off. It's not a networking solution, as it allows no more than eight devices."
Maybe he should have them on the radar, because he's wrong, according to Robin Heydon of wireless silicon maker CSR: "Other people don't understand the details of the specification," he says. Going to low power gave the designers a clean sheet of paper, he says, so low-energy Bluetooth can share antennas with regular Bluetooth, but have a completely different MAC. Regular Bluetooth has a limited number of connections, but its low-power sibling doesn't says Heydon.
"The number of devices is unlimited. The practical limitation depends on how much people want to spend on a particular chip," he says. Oh and it does change frequency, he says, but only between transmissions. It changes frequency between signals. "You want to keep radio on for as small an amount of time as possible, to save power. The best thing is to robustly find a frequency and send all the data."
Low-energy Bluetooth will use a star topology so one master can only talk to slaves that are in range at a given moment, but there could be very many of these, if low-energy Bluetooth appears in devices Heydon predicts, such as watches, shoes and heart monitors.
Is the star topology a weakness compared to ZigBee's mesh? Not at all, says Heydon. In fact, using a mesh is one of ZigBee's mistakes: "You can't do low power and mesh at the same time," he says, pointing out that any mesh relay node can't go to sleep to save power, as it has to stay ready to hand on data it receives. "The only way for nodes to relay info, is to have them on all the time."
The best way to mesh devices is hierarchy, so masters are linked over appropriate technology, he says: "One technology to do it all is actually the wrong design." Heydon expects a lot of data gathered by low-energy Bluetooth to find its way onto the Internet. Perhaps data gathered by Bluetooth bathroom scales would go, via your phone, to a medical website or - God forbid - to your Facebook page.
Medical systems body the Continua Alliance, is looking at using low-energy Bluetooth for just this sort of application, says Heydon. There's no published list of members of Bluetooth SIG's low-power group, but Heydon reckons it's a big cross-section of all silicon vendors - "not just Bluetooth vendors. There's huge industry awareness of this technology."
There's another advantage Zigbee might claim - it uses a published standard, IEEE 802.15.4 for its radio links. But standards aren't documents, says Heydon, they are what is sold in numbers in the market.
And using that radio doesn't even give ZigBee much benefit. "ZigBee doesn't control the radio design," says Heydon. "The only way to really build a low-power low energy system is to build it form the bottom all the way up to the top. The Bluetooth SIG is the only organisation that is capable of doing that."
Other benefits
Heile predicts 600,000 smart electric meters will have ZigBee in them this year, but Heydon thinks Bluetooth has bigger fish to fry: "They can have the electric meters," he says. "You want to control light switches when you are in a chair - and the device you will have with you is your mobile phone."
"The market Zigbee, has been talking about is reducing over time," says Heydon. "The big problem is getting volume and Bluetooth has a big tick box next to it."
It will be a very small additional cost to add low-energy Bluetooth to existing Bluetooth devices, he says, which means the cost of putting it in phones will be close to zero. Silicon companies can start adding it in mid-2009, when the standard is complete, he says, and it should spread rapidly in new mobile phones creating "an instant market" for accessories and home-installed sensors.
This allows other benefits, like presence. For instance, lights can turn on, or your stereo can wake up, when you walk into the room. A car can adapt itself to your preferences when you get in, and a computer can lock itself and maybe turn itself off, when you walk away.
Cellphone Driving Bans Spur Bluetooth Sales
By Nancy Klosek
The growing state bans on cellphone use while driving might be a pain for some motorists, but it is sure to be a boon for many retailers selling Bluetooth accessories.
Industry executives say that as states mandate hands-free cell use, more drivers will be seeking alternatives, such as Bluetooth-enabled accessories. Consumer awareness has been heightened in trend-setting states like
To help convince those and other drivers that Bluetooth is the way to go, manufacturers continue to simplify the operation and setup of the devices.
Cellphone manufacturers are also promoting Bluetooth functionality, enhanced sound quality and battery life of their devices. Meanwhile, industry leaders are lauding the Bluetooth Special Interest Group (SIG) for its efforts to improve education and functionality of the devices.
“The Bluetooth SIG has done an admirable job of improving the technology so that it can transfer more data, faster, making it more useful,” said David Wenning, senior vice president for Parrot, adding that 75 percent of new phones sold in Q4 included Bluetooth. “This has allowed accessory makers to use the technology in millions of devices, and the cellphone makers to incorporate Bluetooth in more and more phones.”
The good news for retailers is that the mobile Bluetooth market is still developing, providing plenty of opportunities for new sales, industry leaders said.
“People are getting more aware of the benefits, but it’s not moving as fast as in Europe and
iLuv i730 is a hands-free car kit for the iPod that affixes to a windshield and features a multi-docking system and FM transmitter for listening to iPods and iPhones through car speakers. It also recharges the source device.
To smooth the bumps in the Bluetooth pairing process, BlueAnt offers a toll-free support center to help users with instructions, said Suzanne Harrison, BlueAnt’s marketing manager. The BlueAnt site also provides online product simulations for devices like the new Supertooth Light visor-mounted hands-free speakerphone and the V1 voice-controlled Bluetooth headset. “It’s people’s perception that Bluetooth is complicated, but that’s just a lack of education,” she said, pointing to a Bluetooth SIG micro site initiative designed to explain Bluetooth’s benefits and features in simple terms. “The goal is to get the site into retail stores and accessed there.”
Although awareness of Bluetooth is growing in states cracking down on hands-on cellphone use in cars, industry executives said there is still much confusion around compliance and user options.
“We’re working to reduce that confusion by educating consumers in-store and online,” Wenning said, adding that the company’s parrotsafedriving.com site includes an overview of hands-free laws in the
Bluetooth helps Facebook friends
A team of
Users register with the Facebook tool, called Cityware, that tracks encounters in the real world via Bluetooth.
It is part of a wider project backed by Nokia, HP Labs and Vodafone.
Dr Vassilis Kostakos, research associate at the
"The really nice thing about Bluetooth is that when you are walking down the street, although you are not talking to anyone, your Bluetooth device can be talking to other devices.
"People with Bluetooth devices are actually creating an ad hoc communications infrastructure where information can flow through the city over time."
He said the project's motivation was in helping people find out more information about "familiar strangers".
'Publicly online'
He said: "Most people you bump into or see regularly have made information about themselves available publicly online.
"But the internet is such a big place that it's difficult to find contextual information about who someone is, where they are etc."
The tool lets users find out if any of the people they bump into regularly is a Cityware user and has a profile of Facebook. If so, they can then choose to add that person to their friends' list.
The tool works in four parts: Facebook account, Cityware application, Bluetooth device and Cityware node.
Users must have a Facebook account, install the Cityware application and register the Bluetooth ID of their mobile phone or laptop with the software.
The researchers have set up a series of nodes around the
These nodes are computers which constantly scan for Bluetooth-enabled devices in a given area, and send that information back to servers which compare the IDs of the gadgets with any enabled Facebook profiles.
From : BBC NEWS
Recommend Bluetooth Stereo Headphones
Product Summary
The good: The Cardo S-2 Bluetooth stereo headset has a comfortable fit, easy-to-use controls, and fantastic sound quality.
The bad: The Cardo S-2 Bluetooth stereo headset did not perform so well in noisy settings.
The bottom line: The Cardo S-2 Bluetooth stereo headset is a great and affordable wireless music solution for those with stereo Bluetooth-enabled phones or music players.
Specs: Type: Microphone Built-in; Product type: Headset; Design: Behind-the-neck
How to Choose a Bluetooth Headset
By:Gregg Hall
Creating a good wireless headset for Bluetooth is actually difficult to do. The regular wired headsets are easy to design - with ranging styles.
Bluetooth headsets can never be as small or as light as wired headsets, simply because it needs to include the battery and extra functions. This extra size will impact how the headset mounts on or around your ears.
Comfort
There seems to be two main styles of headsets for Bluetooth. Some are held into place with a loop around the ear. These styles are normally more comfortable, although they may be less secure. The others are held in place by being jammed into your ear - and usually prove to be less comfortable.
Factors to consider
Cost
The cost is an obvious issue, something that you really need to think about.
Ergonomics
1.Check to see if the device is easy to quickly and conveniently put on your ear then take it off again.
2.Are the control buttons on the headset easy to use?
3.The headset should be comfortable to wear for long phone calls.
4.Can you use it with a pair of glasses?
5.Check to see if you can wear it with either ear.
6.When you aren’t wearing it, you’ll need to se how you would carry it with you.
7.The weight is important as well, as you don’t want something that has the risk of falling off.
Ease of use.
1.The commands and controls should be easy to remember.
2.The volume level should be easy to adjust.
3.The unit should turn on quickly.
4.The manual should be very well written and easy for you to understand.
5.There should be a support number for you to call if you should experience any types of problems.
Features
1.You’ll need to know about the battery, the talk time, type, and how to tell when it is going dead or fully charged.
2.How many devices can the unit be paired with?
3.Compatability is also important, as well as the warranty period.
4.Check the sound quality for both sending and receiving audio.
5.What type of range does the headset offer you?
Other important capabilities include voice tags, last number redial, transfer calls, 3 way calling, link to other phones, call reject, and mute. You’ll also want to note if it looks attractive, and if it’s too big or too small.
Personally I chose to buy a Jabra headset to use with my Palm Treo because of the reliability as well as the look of the headset, it hides behind your ear so it doesn’t look like something from Star Trek.
Creating a good wireless headset for Bluetooth is actually difficult to do. The regular wired headsets are easy to design - with ranging styles.
Bluetooth headsets can never be as small or as light as wired headsets, simply because it needs to include the battery and extra functions. This extra size will impact how the headset mounts on or around your ears.
Comfort
There seems to be two main styles of headsets for Bluetooth. Some are held into place with a loop around the ear. These styles are normally more comfortable, although they may be less secure. The others are held in place by being jammed into your ear - and usually prove to be less comfortable.
Factors to consider
Cost
The cost is an obvious issue, something that you really need to think about.
Ergonomics
1.Check to see if the device is easy to quickly and conveniently put on your ear then take it off again.
2.Are the control buttons on the headset easy to use?
3.The headset should be comfortable to wear for long phone calls.
4.Can you use it with a pair of glasses?
5.Check to see if you can wear it with either ear.
6.When you aren’t wearing it, you’ll need to se how you would carry it with you.
7.The weight is important as well, as you don’t want something that has the risk of falling off.
Ease of use.
1.The commands and controls should be easy to remember.
2.The volume level should be easy to adjust.
3.The unit should turn on quickly.
4.The manual should be very well written and easy for you to understand.
5.There should be a support number for you to call if you should experience any types of problems.
Features
1.You’ll need to know about the battery, the talk time, type, and how to tell when it is going dead or fully charged.
2.How many devices can the unit be paired with?
3.Compatability is also important, as well as the warranty period.
4.Check the sound quality for both sending and receiving audio.
5.What type of range does the headset offer you?
Other important capabilities include voice tags, last number redial, transfer calls, 3 way calling, link to other phones, call reject, and mute. You’ll also want to note if it looks attractive, and if it’s too big or too small.
Personally I chose to buy a Jabra headset to use with my Palm Treo because of the reliability as well as the look of the headset, it hides behind your ear so it doesn’t look like something from Star Trek.
Article Source: http://www.redsofts.com/articles/
Bluetooth Headsets
A bluetooth headset is a discreet device that can be worn on the ear. Relying on bluetooth technology, it establishes connection to the phone, PDA, camera and more. Bluetooth headsets have redefined the idea of talking over the telephone. With the growing number of bluetooth enabled mobile phones, the demand and popularity of bluetooth headsets is increasing day by day. Bluetooth headsets give you the advantage to talk with your hands free. This means that bluetooth headset gives you the ability to do anything while talking.
Bluetooth Special Interest Group
Initially (circa 1996-1997) the technology later known as Bluetooth was an Ericsson-internal project named multi-communicator link or short MC link. Cooperation with Intel was initiated in 1997.
In 1998, Ericsson, IBM, Intel, Toshiba, and
The Bluetooth Special Interest Group (SIG) is a privately held, not-for-profit trade association with headquarters in
From Wikipedia, the free encyclopedia
Origin of the name and the logo
Bluetooth was named after a late tenth century king, Harald Bluetooth, King of Denmark and
The name may have been inspired less by the historical Harald than the loose interpretation of him in The Long Ships by Frans Gunnar Bengtsson, a Swedish Viking-inspired novel.
The Bluetooth logo merges the Germanic runes analogous to the modern Latin letter H and B: (for Harald Bluetooth) (Hagall) and (Berkanan) merged together, forming a bind rune.
From Wikipedia, the free encyclopedia
Health concerns
Bluetooth uses the microwave radio frequency spectrum in the 2.4 GHz to 2.4835 GHz range. Maximum power output from a Bluetooth radio is 100 mW, 2.5 mW, and 1 mW for Class 1, Class 2, and Class 3 devices respectively, which puts Class 1 at roughly the same level as mobile phones, and the other two classes much lower. Accordingly, Class 2 and Class 3 Bluetooth devices are considered less of a potential hazard than mobile phones, and Class 1 may be comparable to that of mobile phones.
From Wikipedia, the free encyclopedia
From Wikipedia, the free encyclopedia
Security
Overview
Bluetooth implements confidentiality, authentication and key derivation with custom algorithms based on the SAFER+ block cipher. In Bluetooth, key generation is generally based on a Bluetooth PIN, which must be entered into both devices. This procedure might be modified if one of the devices has a fixed PIN, e.g. for headsets or similar devices with a restricted user interface. During pairing, an initialization key or master key is generated, using the E22 algorithm. The E0 stream cipher is used for encrypting packets, granting confidentiality and is based on a shared cryptographic secret, namely a previously generated link key or master key. Those keys, used for subsequent encryption of data sent via the air interface, rely on the Bluetooth PIN, which has been entered into one or both devices.
An overview of Bluetooth vulnerabilities exploits has been published by Andreas Becker.
Bluejacking
Bluejacking allows phone users to send business cards anonymously using Bluetooth wireless technology. Bluejacking does NOT involve the removal or alteration of any data from the device. These business cards often have a clever or flirtatious message rather than the typical name and phone number. Bluejackers often look for the receiving phone to ping or the user to react. They then send another, more personal message to that device. Once again, in order to carry out a bluejacking, the sending and receiving devices must be within range of each other, which is typically 10 meters for most mobile devices. Devices that are set in non-discoverable mode are not susceptible to bluejacking. However, the Linux application Redfang claims to find non-discoverable Bluetooth devices.
History of security concerns
2003
In November 2003, Ben and Adam Laurie from A.L. Digital Ltd. discovered that serious flaws in Bluetooth security may lead to disclosure of personal data. It should be noted, however, that the reported security problems concerned some poor implementations of Bluetooth, rather than the protocol itself.
In a subsequent experiment, Martin Herfurt from the trifinite.group was able to do a field-trial at the CeBIT fairgrounds, showing the importance of the problem to the world. A new attack called BlueBug was used for this experiment. This is one of a number of concerns that have been raised over the security of Bluetooth communications.
2004
In 2004 the first purported virus using Bluetooth to spread itself among mobile phones appeared on the Symbian OS. The virus was first described by Kaspersky Lab and requires users to confirm the installation of unknown software before it can propagate. The virus was written as a proof-of-concept by a group of virus writers known as "29A" and sent to anti-virus groups. Thus, it should be regarded as a potential (but not real) security threat to Bluetooth or Symbian OS since the virus has never spread in the wild.
In August 2004, a world-record-setting experiment (see also Bluetooth sniping) showed that the range of Class 2 Bluetooth radios could be extended to 1.78 km (1.08 mile) with directional antennas and signal amplifiers. This poses a potential security threat because it enables attackers to access vulnerable Bluetooth-devices from a distance beyond expectation. The attacker must also be able to receive information from the victim to set up a connection. No attack can be made against a Bluetooth device unless the attacker knows its Bluetooth address and which channels to transmit on.
2005
In April 2005,
In June 2005, Yaniv Shaked and Avishai Wool published a paper describing both passive and active methods for obtaining the PIN for a Bluetooth link. The passive attack allows a suitably equipped attacker to eavesdrop on communications and spoof, if the attacker was present at the time of initial pairing. The active method makes use of a specially constructed message that must be inserted at a specific point in the protocol, to make the master and slave repeat the pairing process. After that, the first method can be used to crack the PIN. This attack's major weakness is that it requires the user of the devices under attack to re-enter the PIN during the attack when the device prompts them to. Also, this active attack probably requires custom hardware, since most commercially available Bluetooth devices are not capable of the timing necessary.
In August 2005, police in
2006
In April 2006, researchers from Secure Network and F-Secure published a report that warns of the large number of devices left in a visible state, and issued statistics on the spread of various Bluetooth services and the ease of spread of an eventual Bluetooth worm.
In October 2006, at the Luxemburgish Hack.lu Security Conference, Kevin Finistere and Thierry Zoller demonstrated and released a remote root shell via Bluetooth on Mac OS X v10.3.9 and v10.4. They also demonstrated the first Bluetooth PIN and Linkkeys cracker, which is based on the research of Wool and Shaked.
2008
As of 2008, despite the hype and warnings of earlier years, no major worm or virus had yet materialized.From Wikipedia, the free encyclopedia
Technical information
Communication and connection
A master Bluetooth device can communicate with up to seven devices. This network group of up to eight devices is called a piconet.
A piconet is an ad-hoc computer network, using Bluetooth technology protocols to allow one master device to interconnect with up to seven active devices. Up to 255 further devices can be inactive, or parked, which the master device can bring into active status at any time.
At any given time, data can be transferred between the master and one other device, however, the devices can switch roles and the slave can become the master at any time. The master switches rapidly from one device to another in a round-robin fashion. (Simultaneous transmission from the master to multiple other devices is possible, but not used much.)
Bluetooth specification allows connecting two or more piconets together to form a scatternet, with some devices acting as a bridge by simultaneously playing the master role and the slave role in one piconet. These devices are planned for 2007.
Many USB Bluetooth adapters are available, some of which also include an IrDA adapter. Older (pre-2003) Bluetooth adapters, however, have limited services, offering only the Bluetooth Enumerator and a less-powerful Bluetooth Radio incarnation. Such devices can link computers with Bluetooth, but they do not offer much in the way of services that modern adapters do.
Setting up connections
Any Bluetooth device will transmit the following information on demand:
- Device name.
- Device class.
- List of services.
- Technical information, for example, device features, manufacturer, Bluetooth specification used, clock offset.
Any device may perform an inquiry to find other devices to connect to, and any device can be configured to respond to such inquiries. However, if the device trying to connect knows the address of the device, it always responds to direct connection requests and transmits the information shown in the list above if requested. Use of device services may require pairing or acceptance by its owner, but the connection itself can be initiated by any device and held until it goes out of range. Some devices can be connected to only one device at a time, and connecting to them prevents them from connecting to other devices and appearing in inquiries until they disconnect from the other device.
Every device has a unique 48-bit address. However these addresses are generally not shown in inquiries. Instead, friendly Bluetooth names are used, which can be set by the user. This name appears when another user scans for devices and in lists of paired devices.
Most phones have the Bluetooth name set to the manufacturer and model of the phone by default. Most phones and laptops show only the Bluetooth names and special programs that are required to get additional information about remote devices. This can be confusing as, for example, there could be several phones in range named T610 (see Bluejacking).
Pairing
Pairs of devices may establish a trusted relationship by learning (by user input) a shared secret known as a passkey. A device that wants to communicate only with a trusted device can cryptographically authenticate the identity of the other device. Trusted devices may also encrypt the data that they exchange over the airwaves so that no one can listen in. The encryption can, however, be turned off, and passkeys are stored on the device file system, not on the Bluetooth chip itself. Since the Bluetooth address is permanent, a pairing is preserved, even if the Bluetooth name is changed. Pairs can be deleted at any time by either device. Devices generally require pairing or prompt the owner before they allow a remote device to use any or most of their services. Some devices, such as mobile phones, usually accept OBEX business cards and notes without any pairing or prompts.
Certain printers and access points allow any device to use its services by default, much like unsecured Wi-Fi networks. Pairing algorithms are sometimes manufacturer-specific for transmitters and receivers used in applications such as music and entertainment.
Air interface
The protocol operates in the license-free ISFrom Wikipedia, the free encyclopedia
Specifications and features
The Bluetooth specification was developed in 1994 by Jaap Haartsen and Sven Mattisson, who were working for Ericsson Mobile Platforms in
The specifications were formalized by the Bluetooth Special Interest Group (SIG), organised by Mohd Syarifuddin. The SIG was formally announced on May 20, 1998. Today it has a membership over 7000 companies worldwide. It was established by Ericsson, Sony Ericsson, IBM, Intel, Toshiba, and
Bluetooth 1.0 and 1.0B
Versions 1.0 and 1.0B had many problems, and manufacturers had difficulty making their products interoperable. Versions 1.0 and 1.0B also included mandatory Bluetooth hardware device address (BD_ADDR) transmission in the Connecting process (rendering anonymity impossible at the protocol level), which was a major setback for certain services planned for use in Bluetooth environments.
Bluetooth 1.1
- Ratified as IEEE Standard 802.15.1-2002.
- Many errors found in the 1.0B specifications were fixed.
- Added support for non-encrypted channels.
- Received Signal Strength Indicator (RSSI).
Bluetooth 1.2
This version is backward-compatible with 1.1 and the major enhancements include the following:
- Faster Connection and Discovery
- Adaptive frequency-hopping spread spectrum (AFH), which improves resistance to radio frequency interference by avoiding the use of crowded frequencies in the hopping sequence.
- Higher transmission speeds in practice, up to 721 kbit/s, as in 1.1.
- Extended Synchronous Connections (eSCO), which improve voice quality of audio links by allowing retransmissions of corrupted packets.
- Host Controller Interface (HCI) support for three-wire UART.
- Ratified as IEEE Standard 802.15.1-2005.
Bluetooth 2.0
This version, specified on November 10, 2004, is backward-compatible with 1.1. The main enhancement is the introduction of an Enhanced Data Rate (EDR) of 3.0 Mbit/s. This has the following effects:
- Three times faster transmission speed—up to 10 times in certain cases (up to 2.1 Mbit/s).
- Lower power consumption through a reduced duty cycle.
- Simplification of multi-link scenarios due to more available bandwidth.
The practical data transfer rate is 2.1 megabits per second and the basic signalling rate is about 3 megabits per second. The "Bluetooth 2.0 + EDR" specification given at the Bluetooth Special Interest Group (SIG) includes EDR and there is no specification "Bluetooth 2.0" as used by many vendors. The HTC TyTN pocket PC phone, shows "Bluetooth 2.0 without EDR" on its data sheet. In many cases it is not clear whether a product claiming to support "Bluetooth 2.0" actually supports the EDR higher transfer rate.
Bluetooth 2.1
Bluetooth Core Specification Version 2.1 is fully backward-compatible with 1.1, and was adopted by the Bluetooth SIG on July 26, 2007. This specification includes the following features:
- Extended inquiry response: provides more information during the inquiry procedure to allow better filtering of devices before connection. This information includes the name of the device, a list of services the device supports, as well as other information like the time of day, and pairing information.
- Sniff subrating: reduces the power consumption when devices are in the sniff low-power mode, especially on links with asymmetric data flows. Human interface devices (HID) are expected to benefit the most, with mouse and keyboard devices increasing the battery life by a factor of 3 to 10. It let devices decide how long they will wait before sending keepalive messages to one another. Previous Bluetooth implementations featured keep alive message frequencies of up to several times per second. In contrast, the 2.1 specification allows pairs of devices to negotiate this value between them to as infrequently as once every 5 or 10 seconds.
- Encryption Pause Resume: enables an encryption key to be refreshed, enabling much stronger encryption for connections that stay up for longer than 23.3 hours (one Bluetooth day).
- Secure Simple Pairing: radically improves the pairing experience for Bluetooth devices, while increasing the use and strength of security. It is expected that this feature will significantly increase the use of Bluetooth.
- NFC cooperation: automatic creation of secure Bluetooth connections when NFC radio interface is also available. For example, a headset should be paired with a Bluetooth 2.1 phone including NFC just by bringing the two devices close to each other (a few centimeters). Another example is automatic uploading of photos from a mobile phone or camera to a digital picture frame just by bringing the phone or camera close to the frame.
Future of Bluetooth
- Broadcast Channel: enables Bluetooth information points. This will drive the adoption of Bluetooth into mobile phones, and enable advertising models based around users pulling information from the information points, and not based around the object push model that is used in a limited way today.
- Topology Management: enables the automatic configuration of the piconet topologies especially in scatternet situations that are becoming more common today. This should all be invisible to the users of the technology, while also making the technology just work.
- Alternate MAC PHY: enables the use of alternative MAC and PHY's for transporting Bluetooth profile data. The Bluetooth Radio will still be used for device discovery, initial connection and profile configuration, however when lots of data needs to be sent, the high speed alternate MAC PHY's will be used to transport the data. This means that the proven low power connection models of Bluetooth are used when the system is idle, and the low power per bit radios are used when lots of data needs to be sent.
- QoS improvements: enable audio and video data to be transmitted at a higher quality, especially when best effort traffic is being transmitted in the same piconet.
High-speed Bluetooth
On 28 March 2006, the Bluetooth Special Interest Group announced its selection of the WiMedia Alliance Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) version of UWB for integration with current Bluetooth wireless technology.
UWB integration will create a version of Bluetooth wireless technology with a high-speed/high-data-rate option. This new version of Bluetooth technology will meet the high-speed demands of synchronizing and transferring large amounts of data, as well as enabling high-quality video and audio applications for portable devices, multi-media projectors and television sets, and wireless VOIP.
At the same time, Bluetooth technology will continue catering to the needs of very low power applications such as mice, keyboards, and mono headsets, enabling devices to select the most appropriate physical radio for the application requirements, thereby offering the best of both worlds.
Bluetooth 3.0
The next version of Bluetooth after v2.1, code-named
Ultra Low Power Bluetooth
On June 12, 2007,From Wikipedia, the free encyclopedia
Computer requirements
A personal computer must have a Bluetooth adapter in order to be able to communicate with other Bluetooth devices (such as mobile phones, mice and keyboards). While some desktop computers and most recent laptops come with a built-in Bluetooth adapter, others will require an external one in the form of a dongle.
Unlike its predecessor, IrDA, which requires a separate adapter for each device, Bluetooth allows multiple devices to communicate with a computer over a single adapter.
Operating system support
Apple has supported Bluetooth since Mac OS X v10.2 released in 2002.
For Microsoft platforms, Windows XP Service Pack 2 and later releases have native support for Bluetooth. Previous versions required users to install their Bluetooth adapter's own drivers, which were not directly supported by Microsoft. Microsoft's own Bluetooth dongles (packaged with their Bluetooth computer devices) have no external drivers and thus require at least Windows XP Service Pack 2.
Linux provides two Bluetooth stacks, with the BlueZ stack included with most Linux kernels. It was originally developed by Qualcomm and Affix. BlueZ supports all core Bluetooth protocols and layers.
From Wikipedia, the free encyclopedia
Uses
Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device.
Bluetooth enables these devices to communicate with each other when they are in range. The devices use a radio communications system, so they do not have to be in line of sight of each other, and can even be in other rooms, as long as the received transmission is powerful enough.
In most cases the effective range of class 2 devices is extended if they connect to a class 1 transceiver, compared to pure class 2 network. This is accomplished by the higher sensitivity and transmission power of Class 1 devices.
In order to use Bluetooth, a device must be compatible with certain Bluetooth profiles. These define the possible applications and uses of the technology.
More prevalent applications of Bluetooth include:
- Wireless control of and communication between a mobile phone and a hands-free headset. This was one of the earliest applications to become popular.
- Wireless networking between PCs in a confined space and where little bandwidth is required.
- Wireless communications with PC input and output devices, the most common being the mouse, keyboard and printer.
- Transfer of files between devices with OBEX.
- Transfer of contact details, calendar appointments, and reminders between devices with OBEX.
- Replacement of traditional wired serial communications in test equipment, GPS receivers, medical equipment, bar code scanners, and traffic control devices.
- For controls where infrared was traditionally used.
- Sending small advertisements from Bluetooth enabled advertising hoardings to other, discoverable, Bluetooth devices.
- Two seventh-generation game consoles, Nintendo's Wii and Sony's PlayStation 3 use Bluetooth for their respective wireless controllers.
- Dial-up internet access on personal computer or PDA using a data-capable mobile phone as a modem.
Bluetooth and Wi-Fi have slightly different applications in today's offices, homes, and on the move: setting up networks, printing, or transferring presentations and files from PDAs to computers. Both are versions of unlicensed spread spectrum technology.
Bluetooth differs from Wi-Fi in that the latter provides higher throughput and covers greater distances, but requires more expensive hardware and higher power consumption. They use the same frequency range, but employ different modulation techniques. While Bluetooth is a replacement for a variety of applications, Wi-Fi is a replacement only for local area network access. Bluetooth can be thought of as wireless USB, whereas Wi-Fi is wireless Ethernet, both operating at much lower bandwidth than the cable systems they are trying to replace. However, this analogy is not entirely accurate since any Bluetooth device can, in theory, host any other Bluetooth device—something that is not universal to USB devices, therefore it would resemble more a wireless FireWire.
Bluetooth
Bluetooth exists in many products, such as phones, printers, modems and headsets. The technology is useful when transferring information between two or more devices that are near each other in low-bandwidth situations. Bluetooth is commonly used to transfer sound data with phones (i.e. with a Bluetooth headset) or byte data with hand-held computers (transferring files).
Bluetooth simplifies the discovery and setup of services between devices. Bluetooth devices advertise all of the services they provide. This makes using services easier because there is no longer a need to setup network addresses or permissions as in many other networks.
Wi-Fi
Wi-Fi is more like a traditional Ethernet network, and requires configuration to set up shared resources, transmit files, and to set up audio links (for example, headsets and hands-free devices). It uses the same radio frequencies as Bluetooth, but with higher power resulting in a stronger connection. Wi-Fi is sometimes called "wireless Ethernet." This description is accurate as it also provides an indication of its relative strengths and weaknesses. Wi-Fi requires more setup, but is better suited for operating full-scale networks because it enables a faster connection, better range from the base station, and better security than Bluetooth.From Wikipedia, the free encyclopedia
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