Bluetooth Versions

Bluetooth Specification Version 1.1 and Earlier

Several Bluetooth specification versions have been released since Bluetooth technology was introduced in 1998.
Versions 1.0 and 1.0B had too many problems and restraints for manufacturers to successfully develop Bluetooth devices. The main issue was the lack of interoperability among devices.
The Bluetooth Core Specification version 1.1 is the first truly successful operating version of Bluetooth technology. Bluetooth 1.1 corrected many of the problems found in the earlier versions. As a result: Devices using Bluetooth 1.1 have much greater interoperability.

Bluetooth Version 1.2

Many new Bluetooth devices, like the latest cell phones, are being sold with the newer Bluetooth specification version 1.2. So, what new features/benefits does Bluetooth 1.2 offer?

• Backward compatible with Bluetooth 1.1
• Adaptive Frequency Hopping - helps reduce radio interference by eliminating the use of crowded frequencies in the hopping sequence
• Faster transmission speeds (1 Mbps)
• Extended Synchronous Connections Oriented links - improves voice quality of audio connections by enabling retransmissions of corrupted data.
• Received Signal Strength Indicator
• Host Controller Interface (HCI) support for 3-wire UART
• HCI access to timing information for Bluetooth applications

Bluetooth Version 2.0 + EDR (Enhanced Data Rate)

There may be multiple communication technologies, but they all share one thing in common: Faster is better. The Bluetooth SIG realized this, and worked on improving the speeds of Bluetooth version 1.2. Bluetooth version 2.0 + EDR was announced by the Bluetooth SIG in June 2004 and began appearing in Bluetooth devices in late 2005. Bluetooth version 2.0 + EDR delivers data transfer rates up to three times faster than the original Bluetooth specification. Bluetooth version 2.0 + EDR also provides enhanced multiple-connectivity. With Bluetooth 2.0 + EDR, users will be able to more efficiently run multiple Bluetooth devices at the same time. As a result, Bluetooth Personal-Area Networks (PAN) or Piconets will become more common.
For example, users will have the ability to synchronize a Bluetooth enabled computer with a Bluetooth PDA, and at the same time they can listen to music using a pair of Bluetooth wireless headphones.
Computers and computer related devices have been some of the 1st devices to use Bluetooth 2.0 + EDR, while audio and imaging devices are expected to follow shortly. Sony announced it will use Bluetooth 2.0 + EDR in its new PlayStation 3. The PlayStation 3 will reportedly use it for the wireless controllers.
Here is a listing of the main enhancements/features you will find with Bluetooth Specification Version 2.0 + EDR:

• Backward compatible with previous Bluetooth versions
• Three times faster transmission speed (10 times in some cases)
• Enhanced data rate of up to 3 Mbps
• Lower power consumption due to reduced duty cycles
• Broadcast/multicast support
• Simplification of multi-link scenarios due to more available bandwidth
• Distributed media-access control protocols
• Further improved Bit Error Rate performance

Bluetooth Version 2.1 + EDR (Enhanced Data Rate)

Enhancements with Bluetooth Core Version 2.1 + EDR include:

• Improved Pairing
• Enhanced Power Optimization

Bluetooth Version 3.0 + HS (High Speed)

Consumer devices using Bluetooth Version 3.0 + HS will take advantage of higher data rates utilizing the 802.11 radio while still maintaining the classic Bluetooth interface. With Version 3.0, high speed will no longer require an established network architechure.
There are two key features that consumers will benefit from Bluetooth 3.0 + HS:

• Unicast Connectionless Data - lowers latency and provides faster more reliable experiences
• Enhanced Power Control - ensures less dropouts; a common complaint amount Bluetooth users

Manufacturers will also benefit from Bluetooth Version 3.0 + HS. The quality of companies' Bluetooth products increase while, at the same time, reducing manufacturing costs. With testing now standardized and automated, getting new Bluetooth products to market will be much simpler and quicker.

What is Bluetooth Technology

The short description: Bluetooth technology is a global short-range wireless standard that allows a broad range of electronic devices to connect and communicate with each other. Bluetooth technology is essentially a cable-replacement technology. From mobile phones and headsets to MP3 players, PCs and peripherals, Bluetooth technology allows these devices to connect.

Solving Problems

Problem: Today, electronics that connect to one another are found everywhere--in the office, home, Car, etc. Keyboards connect to computers, MP3 players to headphones and so on. So, how do these devices connect to each other? Usually the answer is: with wires and cables. But, as you know, wires and cables always result in a tangled mess.
Solution: Bluetooth wireless technology eliminates many of the wires that clutter our offices, homes, etc., while allowing our electronic devices of today and tomorrow to communicate with one another.

You Hear About it Everywhere

Bluetooth technology has been around for years, however for many people it is just another “tech” term.
Most people have little or no understanding of the technology and have very little knowledge of its applications. However, you hear and read about it everywhere--in ads for computers, Cell Phones, smartphones and various other devices.

Look Mom: No Wires!

What is Bluetooth technology? Put simply, Bluetooth technology is a short-range wireless radio technology that allows electronic devices to connect to one another. Generally, Bluetooth has a range of up to 30 ft. or greater, depending on the Bluetooth Core Specification Version. Newer devices, using newer versions of Bluetooth, have ranges over 100 ft.
Bluetooth wireless technology makes connections just like cables connect a computer to a keyboard, mouse, or printer, or how a wire connects an MP3 player to headphones.
Bluetooth technology makes these same connections, except it does it without the cables and wires. With Bluetooth there is no more worrying about which cable goes where, while getting tangled in the mess.
To learn more about the advantages of wireless technology, click: Wireless Advantages

Setting the Standard

Bluetooth technology is actually derived from a combination of wireless technologies. The Bluetooth specification unites these technologies under the title: "Bluetooth technology".
Bluetooth technology was first developed by Ericsson and then formalized by a group of electronics manufacturers (Ericsson, IBM, Intel, Nokia, and Toshiba) who joined forces to form a private trade association known as the Bluetooth Special Interest Group (SIG).
When they formally introduced the Bluetooth specification to the public, they established a global standard, thus creating a universal way for mobile computers, cell phones, and various other devices to wirelessly connect with one another.
Due to the fact that Bluetooth technology is a standardized wireless technology, you can rest assure it will be around for many years to come.
So, now that we've answered the question: "What is Bluetooth technology?" You probably want to know why this wireless technology was given such a funny name: "Bluetooth".
To learn about the origin of the "Bluetooth" name and the general history of Bluetooth technology, click: Bluetooth History

Bluetooth History

The Bluetooth SIG

The name “Bluetooth” and its logo are trademarked by the privately held trade association named the Bluetooth Special Interest Group (SIG). 
Founded in September 1998, the Bluetooth SIG is a unification of leaders in the telecommunications, computing, network, industrial automation, and Automotive industries. Today, the Bluetooth SIG is responsible for encouraging and supporting research and development in Bluetooth technology.
The Bluetooth SIG includes promoter member companies Microsoft, Ericsson, IBM, Intel, Agere, Motorola, Nokia, and Toshiba, plus thousands of Associate and Adopter member companies (BlueTomorrow.com's parent company, SP Commerce LLC, is a licensed and certified Adopter member of the Bluetooth SIG).

Why is It Called Bluetooth?

The developers of this wireless technology first used the name "Bluetooth" as a code name, but as time past, the name stuck.
The word "Bluetooth" is taken from the 10th century Danish King Harald Bluetooth. King Bluetooth had been influential in uniting Scandinavian Europe during an era when the region was torn apart by wars and feuding clans.
The founders of the Bluetooth SIG felt the name was fitting because:
1) Bluetooth technology was first developed in Scandinavia, and
2) Bluetooth technology is able to unite differing industries such as the cell phone, computing, and automotive markets. Bluetooth wireless technology simplifies and combines multiple forms of wireless communication into a single, secure, low-power, low-cost, globally available radio frequency.

Where Did the Logo Come From?

A Scandinavian firm originally designed the logo at the time the SIG was formally introduced to the public. Keeping to the same origin as the Bluetooth name, the logo unites the Runic alphabetic characters "H", which looks similar to an asterisk, and a "B", which are the initials for Harald Bluetooth. If you look close enough you can see both embodied in the logo.

Bluetooth Technology Over the Years

1998 - Bluetooth technology is officially introduced and the Bluetooth SIG is formed. Bluetooth technology's intended basic purpose is to be a wire replacement technology in order to rapidly transfer voice and data.
1999 - Bluetooth 1.0 Specification is introduced.
2003 - The Bluetooth SIG overhauls the Bluetooth Core Specification with the announcement of Version 2.1.
2004 - Bluetooth Version 2.0 + EDR (Enhanced Data Rate) is introduced.
2005 - Devices using Version 2.0 + EDR begin to hit the market in late 2005.
2007 - Bluetooth Core Specification Version 2.1 + EDR is adopted by the Bluetooth SIG.
2009 - Bluetooth Core Specification Version 3.0 + HS (High Speed) is adopted by the Bluetooth SIG.
For a lising of the different Bluetooth versions and the various features / benefits they provide, please click Bluetooth Core Specification Versions

High Speed Bluetooth

In March 2006, the Bluetooth Special Interest Group (SIG) announced that it was planning to partner with WiMedia Alliance (an industry group composed of such computer giants as Intel, Hewlet-Packard and Microsoft) to bring consumers the best of both worlds with the creation of a new High Speed Bluetooth. Bluetooth is currently used to facilitate slow-speed, short-range applications such as wireless headsets and keyboards. Yet, while its high portability, low power requirements and unique hit-and-run frequency hopping has maintained a lot of interest among critics and consumers, for those who live in the fast lane Bluetooth has been lagging. Until now. UWB, short for Ultra-Wideband technology, is the new kid on the block. Much simpler to build and maintain than Wi-Fi, UWB can also support more users at a higher speed, and with Bluetooth it will use only one ten-thousandth of the power that a normal cell phone requires. However, perhaps the most promising trait of UWB technology is that it prefers not to follow the crowd. This kid doesn’t carry a continuous signal, preferring instead to put out bursts of energy over a wide area, rather like Bluetooth’s own mode of operation. UWB operates in the same frequency as TV monitors, electric razors and fans, and can work in the currently unlicensed radio spectrum that lies above 6 GHz. Little interference (and competition!) means less troubleshooting for the techno-savvy-but-far-from-perfect public.
For those whose interests extend only to how fast this new friend can take them where they want to go, UWB will work along with BlueCore4, the Enhanced Data Rate (or EDR) standard that was ratified by the Bluetooth SIG at the end of 2004. Bluetooth EDR offers speeds of up to 2.1Mbps, a good three times that of original Bluetooth capabilities. This partnership, which will essentially lead to the creation of High Speed Bluetooth, translates to about an 8 second/MB faster data transfer speed. As a result, download speeds for iPods, digital cameras, PCs, etc. will be dramatically improved.
Imagine being able to download an entire album of MP3 songs or hundreds of camera phone images in under a second! How about streaming HD video from a camcorder or advanced mobile phone to a TV. Furthermore, think about the possibility of connecting that same mobile phone to friends' phones in order to play multi-player games. With High Speed Bluetooth, these amazing concepts will eventually become a reality!
Motorola's vision of High Speed Bluetooth, takes these concepts even further. They present a scenario where movies can be downloaded from High Speed Bluetooth enabled kiosks located in malls or airports. Under this concept, you could quickly download movies to a mobile phone, PDA, laptop or any other type of compatible device. Motorola goes on to paint a picture of how you could walk up to a kiosk right before boarding a plane and wirelessly download a movie. Then, once onboard, you could watch the movie directly from the device you downloaded it to, or you could stream it to another device with a larger display (for example, a mobile phone streaming to a laptop).
The functional process of High Speed Bluetooth (or the Bluetooth/UWB partnership) has been likened to a hybrid car. Bluetooth capabilities remain a constant hum, where the UWB, which requires more power, kicks on only when called upon to speed transfer rates or to download large amounts of information or data. Whatever the method, Bluetooth and UWB will both benefit by coming together; their complementary specifications—UWB’s high power consumption versus low-cost and low-power needs for Bluetooth, and high speed capabilities for UWB/low speed for Bluetooth—are sure to appeal to a technologically hungry consumer base.
Final prototyping for the new High Speed Bluetooth should be done with by the fourth quarter of 2007, which means that consumers could see devices available as soon as 2008.

Wireless Advantages

Here is a list (organized by application type) of some of the advantages wireless technology offers with various devices:
Computer

• Free your desktop of wires and be able to move your mouse in any direction without having to pull on a cord. Allow yourself to kick back with your Keyboard on your lap while you play a game
• Use a small, Portable Mouse with your laptop and don't worry if the cord will be long enough

Surf and Sync

• Need to check your email or a web page on your laptop? Create a GPRS connection to the Internet with your cell phone, then connect your phone and computer using Bluetooth. Your laptop is now online
• Wirelessly synchronize your calendar and contacts between your PDA and computer

Entertainment

• Wireless multiplayer gaming (Check out the N-Gage™ Game Deck)
• With a Bluetooth enabled headset, you can listen to MP3s or FM radio on your phone without wires getting in the way, and with most Bluetooth Headsets the music stops automatically if you get an incoming call

Audio

• Use a headset supporting Bluetooth and lose the wires while still being able to connect to your Bluetooth enabled phone
• Bluetooth wireless headsets also allow you to connect to a Bluetooth enabled computer so you can take advantage of Voice Over Internet Protocol (VOIP) phone service or voice-recognition software

Car

• Use a Bluetooth GPS Receiver with your compatible PDA and create the navigational system you've always wanted
• Get in your car and your Bluetooth enabled cell phone and Bluetooth Car Kit automatically make a connection

Imaging

• Send pictures to another phone, computer, PDA or any other compatible Bluetooth device
• Print images directly from your phone, without having to connect any cables to your printer

How Bluetooth Works - Personal Area Network

Personal-Area Network (PAN) or Piconet

When two or more Bluetooth devices, sharing the same profile(s), come in range of one another, they establish a connection automatically. So, the user doesn’t have to press any buttons or set anything up. Once the Bluetooth devices are all connected, a network is created.
Bluetooth devices create a Personal-area Network (PAN), or commonly called a piconet (It is important that you know and remember what a piconet is, because we refer to it a lot throughout the rest of this site).
Bluetooth piconets are designed to link up to eight different devices. A piconet can be as small as a two foot connection between a keyboard and computer, or it can encompass several devices over an entire room.
Furthermore, it is possible for multiple, distinct piconets to be operating in the same room at any given moment. Devices that are apart of a specific piconet, based on their profiles, use “Hopping” simultaneously so they stay in touch with one another and avoid other piconets that may be operating in the same room.
In order to regulate communications one of the participating devices is assigned the role of "master" of the piconet, while all other units become "slaves" (Talk about a harsh name). Masters have the duty of directing and controlling communications, even between two slave devices.
Under the current Bluetooth specification, up to seven slaves and one master can actively communicate. Furthermore, in order to extend these networks, several piconets can be joined together in what is known as a scatternet.
In theory, anyone with a compatible Bluetooth device is supposed to have the ability to hook up anywhere within that network and connect to another Bluetooth device.

Extended Synchronous Connection Oriented Links

It is a long term, but here is what it means:
With the introduction of Bluetooth version 2.0 + EDR (Enhanced Data Rate), the latest of the Bluetooth Core Specification Versions, the ability to form larger more diverse piconets is greatly improved.
One factor that contributes to more improved piconets is the addition of the extended Synchronous Connection Oriented (eSCO) link type. The eSCO link type allows Bluetooth devices to monitor and retransmit voice packets to improve the quality of the link. This is an especially important advancement to wireless devices that transmit audio data, like stereo headphones and headsets.

Bluetooth Advantages - Why Use Bluetooth?

Main Reasons to Use a Bluetooth Device:

1. Bluetooth Devices are Wireless
If you navigate through the rest of our site you will learn that there are tons of advantages/benefits when using wireless devices. In addition to improving safety as a result of eliminating the clutter of wires and associated hazardous connections, wireless technology also offers many convenient advantages. For example, when you are traveling with your laptop, PDA, MP3 player and other devices, you no longer have to worry about bringing along all of your connecting cables.
For a more detailed list of the advantages associated with wireless connectivity, click on: Wireless Advantages
2.  Bluetooth Technology is Inexpensive
Bluetooth technology is cheap for companies to implement, which results in lower over-all manufacturing Costs. These savings are then passed on to you, the consumer. The end result: Bluetooth devices are relatively inexpensive.
3.  Bluetooth is Automatic
Bluetooth doesn't require you to think about setting up a connection or to push any buttons. When two or more Bluetooth devices enter a range (Up to 30 feet) of one another, they automatically begin to communicate without you having to do anything. Once the communicating begins, Bluetooth devices will setup Personal Area Networks or Piconets. The best part is: The devices take care of the entire setup process, and you can go about your business.
4. Standardized Protocol = Interoperability
Since Bluetooth is a standardized wireless specification, a high level of compatibility among devices is guaranteed. The Bluetooth specification uses and defines various profiles. Every Bluetooth profile is specific to a particular function. For instance, when a Bluetooth enabled cell phone and a Bluetooth headset (Both with the same profile) are communicating with one another, both will understand each other without the user having to do anything, even if the devices are of different models/makes.
To learn more about profiles, click Bluetooth Profiles
5. Low Interference (If Any) Bluetooth devices avoid interference with other wireless devices by:
a) Using a technique known as spread-spectrum frequency hopping, and
b) Using low power wireless signals.
6. Low Energy Consumption
As stated above, Bluetooth uses low power signals. As a result, the technology requires little energy and will therefore use less battery or electrical power. Obviously, this is a great benefit for mobile devices because Bluetooth won't drain the life of your device's battery.
7. Share Voice and Data
The Bluetooth standard allows compatible devices to share both voice and data communications. For example, it is probably no surprise that a Bluetooth enabled cell phone is capable of sharing voice communications with a compatible Bluetooth headset, however, the same cell phone may also be capable of establishing a GPRS connection to the Internet. Then, using Bluetooth, the phone can connect to a laptop. The result: The laptop is capable of surfing the web or sending and receiving email.
8. Instant Personal Area Network (PAN)
Up to seven compatible Bluetooth devices can connect to one another within a proximity of up to 30 feet, forming a PAN or piconet. Multiple piconets can be automatically setup for a single room.
9. Upgradeable
The Bluetooth standard is upgradeable. A development group at the Bluetooth Special Interest Group (SIG) has been given the task of working on the new Bluetooth version 2, which offers several new advantages and is backward compatible with the older versions.
10. The Technology is Here to Stay
Bluetooth is a universal, world-wide, wireless standard. Therefore, you can count on it being around for years to come. As more devices begin to use Bluetooth technology, electronics manufacturers will be increasingly eager to make their products compatible, using Bluetooth. A chain reaction is inevitable, in fact, it has already begun.

Listing of Bluetooth Profiles

All Bluetooth devices must have a “foundation profile”, one that all other Bluetooth profiles are dependent upon.
This profile is called the Generic Access Profile (GAP). It defines the basic procedures for detecting other Bluetooth devices (idle mode procedures) and link management aspects of connecting to Bluetooth devices (connecting mode procedures). It also defines procedures related to the use of different security levels.
In theory, any two Bluetooth devices should be able to connect at a basic level, since they all support this profile; even if it’s just in order to determine that they don’t share any common functions or applications.
All the other profiles operate on top of the GAP and depend on it. Furthermore, some of these profiles have other profiles located above them.
For example, above the GAP are the Serial Port Profile (SPP), Generic Object Exchange Profile (GOEP), and Synchronization Profile (SYNC). Many of the most common profiles, such as the Headset Profile (HSP) and Fax Profile rely on the SPP.
So, if you want to synchronize your Bluetooth-enabled smartphone with your Bluetooth-enabled computer, both will have to support the GAP, the SPP, the GOEP and the SYNC. But there’s no need for them to have any of the other profiles (unless of course you want them to perferm other functions).
Here is a listing of the most commonly used, current Bluetooth profiles:

• Advanced Audio Distribution Profile (A2DP)
• Audio/Video Remote Control Profile (AVRCP)
• Basic Imaging Profile (BIP)
• Basic Printing Profile (BPP)
• Common ISDN Access Profile (CIP)
• Cordless Telephony Profile (CTP)
• Dial-up Networking Profile (DUN)
• Fax Profile (FAX)
• File Transfer Profile (FTP)
• Generic Audio/Video Distribution Profile (GAVDP)
• Generic Access Profile (GAP)
• Generic Object Exchange Profile (GOEP)
• Hands-Free Profile (HFP)
• Hardcopy Cable Replacement Profile (HCRP)
• Headset Profile (HSP)
• Human Interface Device Profile (HID)
• Intercom Profile (ICP)
• Object Push Profile (OPP)
• Personal Area Networking Profile (PAN)
• Serial Port Profile (SPP)
• Service Discovery Application Profile (SDAP)
• Synchronization Profile (SYNC)
• Video Distribution Profile (VDP)

Additional profiles include:

• Device Identification Profile (DI)
• Health Device Profile (HDP)
• Message Access Profile (MAP)
• Phone Book Access Profile (PBAP)
• SIM Access Profile (SAP)

How Bluetooth Works - Signal Strength, Frequency, and Profiles

Bluetooth: Low Power and Low Cost!

Bluetooth wireless technology operates on an open frequency within the 2.4 gigahertz band, which is the same as WiFi, cordless phones and various other wireless devices. Bluetooth is able to share the same frequency band without experiencing any interference because it utilizes various key technologies.
One of the ways Bluetooth avoids interference is through the use of low power signals (around one milliwatt). Devices using the Bluetooth Core Specification Version 1.1 or later (To learn about the different Bluetooth versions, click: Bluetooth Core Specification Versions) are able to avoid interference with other wireless devices because their signal is so weak.
Take into consideration that powerful cell phones use a signal of around three watts. Even though the signal is weaker, Bluetooth still offers a range of up to 30 feet (Newer versions can have a range over 100 feet).
The signal is also capable of passing through the walls in your home, making it useful for controlling several devices in different rooms. Data can be transferred at a rate of up to one Megabyte per second (Mbps).
Also, because Bluetooth transmitters require minimal amounts of power, they are relatively inexpensive to manufacture. Simply put, Bluetooth uses low-power radio waves to reliably communicate in an inexpensive way.

“Hopping” = No Interference

Another way Bluetooth devices are able to avoid interference is through a technique known as spread-spectrum frequency hopping. By using the “hopping” method, a device will use one of 79 different, randomly chosen frequencies within an assigned range, and will frequently change frequencies from one to another.
Bluetooth enabled devices, which all use the “hopping” method, change frequencies 1,600 times per second. As a result, more devices can use a portion of the radio spectrum.
The risk of a device like a cell phone or baby monitor interfering with Bluetooth devices is minimized, since any interference on a specific frequency will last for only a fraction of a second.
Bluetooth version 2.0 + EDR, the very latest of the Bluetooth specification versions, uses an enhanced technology called: Adaptive Frequency Hopping (AFH).
AFH allows Bluetooth devices to measure the quality of the wireless signal and then determine if there are bad channels present on specific frequencies due to interference from other wireless devices.
If bad channels are present on a specific frequency, the Bluetooth device will adjust its hopping sequence to avoid them. As a result, the Bluetooth connection is stronger, faster, and more reliable.

Bluetooth Profiles: How Bluetooth is Used

Bluetooth enabled devices must use and understand certain Bluetooth "profiles" in order to use Bluetooth technology to connect to one another. These profiles define the possible applications that a Bluetooth enabled device can support.
In order for one Bluetooth device to connect to another, both devices must share at least one of the same Bluetooth profiles.
To learn more about profiles and why they are important to those using Bluetooth devices, click: Bluetooth Profiles

Bluetooth Profiles

Overview of Bluetooth Profiles

The Bluetooth SIG states, "Bluetooth profiles are general behaviors through which Bluetooth enabled devices communicate with other devices."
In order to connect to one another, devices that use Bluetooth technology must support and understand certain Bluetooth profiles. Bluetooth profiles define the possible applications and describe how Bluetooth technology is to be used for each specific device.
For example, the File Transfer profile is used to define how devices like a PDA will use Bluetooth Technology to transfer files to other devices like another PDA, cell phone, or computer.
When a Bluetooth device is developed, the manufacturer assigns (In accordance with the Bluetooth SIG's requirements) specific Bluetooth profiles for that device to use in order to establish applications which will work with other Bluetooth devices.
In order for one Bluetooth device to connect to another, both devices must share at least one of the same Bluetooth profiles.
For example, if you want to use a Bluetooth headset with your Bluetooth enabled cell phone, both devices must use the Headset (HS) profile (Defines how headsets and cell phones use Bluetooth technology to connect to one another).
According to the Bluetooth SIG: At minimum, every Bluetooth profile includes information on the following issues:

• Dependencies on other profiles.
• Recommended user interface formats.
• Particular parts of the Bluetooth protocol stack used by the profile. To perform its functions, each profile uses particular options and parameters at each layer of the stack. This may include an outline of the required service record, if applicable.

Most Bluetooth devices are given just a few profiles. For example, a Bluetooth headset will use the Headset Profile, but not the LAN Access Profile (Defines how devices use Bluetooth technology to connect to local area networks).

Progression of Bluetooth Profiles

There are currently 25 Bluetooth profiles which have been officially adopted and are in use. Most of the Bluetooth profiles were introduced with the Bluetooth Core Specification version 1.1. The Bluetooth SIG governs the development of new Bluetooth profiles.
With the continual growth of Bluetooth technology, Bluetooth profiles will continue to be enhanced and expanded upon. As more profiles are developed, the overall Bluetooth specification is updated and reformatted so that the entire thing doesn’t have to be rewritten.

How are Bluetooth Profiles Important to Me?

Just because a product is advertised as a Bluetooth device, doesn't mean it's capable of connecting to every other Bluetooth device in existence. A device that is "Bluetooth-enabled" simply means it has at least one Bluetooth profile which would allow it to connect with another Bluetooth device that shares the same profile(s). However, if the other Bluetooth device does not share the same profile(s), the devices cannot connect
When buying a Bluetooth-enabled product you should find out what Bluetooth functions/services the device supports. These functions will usually spell out what Bluetooth profiles the product uses. Don’t worry, most of the time you don't even need to worry about profiles when buying a Bluetooth device.
The specifications on the manufacturer’s website, retailer’s website (i.e. Amazon) or on the retail box for a Bluetooth device should explain everything you need to know. Such as: what other devices it's compatible with, what it can do, and any system requirements (Our buying guides give you all this information).
Most of the time the specific Bluetooth profiles won't be of much importance to you. However, when you are trying to expand a device's functions or use it with another Bluetooth device that's not listed as compatible, then it is highly recommended that you find out what specific profiles are used.

What Profiles Does a Device Support?

Each Bluetooth profile has a specialized use. So, you can find out which Bluetooth devices are compatible by knowing what Bluetooth profile(s) they support. Finding out what profile(s) a device supports is usually an easy, quick process.
For example, you know a Bluetooth enabled printer is going to support the Basic Printing Profile. But, if you have a PDA with Bluetooth technology, things may be a little more complicated. A Bluetooth enabled PDA usually supports several profiles, such as the Synchronization Profile, LAN Access Profile, File Transfer Profile and others.
For a listing of every Bluetooth device and the profiles they support, please visit: the Bluetooth Qualification Website.

Bluetooth Pairing

If you are familiar with Bluetooth wireless technology, you'll probably recognize the term "Bluetooth pairing". But do you actually know what Bluetooth pairing means?
Bluetooth pairing occurs when two Bluetooth devices agree to communicate with each other and establish a connection.
In order to pair two Bluetooth wireless devices, a password (passkey) has to be exchanged between the two devices. A Passkey is a code shared by both Bluetooth devices, which proves that both users have agreed to pair with each other.
This is the normal process that occurs with Bluetooth pairing:

1. Bluetooth device A looks for other Bluetooth devices in the area
In order to find other Bluetooth devices, Bluetooth device A must be set to discoverable mode. When set to discoverable, Bluetooth device A will allow other Bluetooth devices to detect its presence and attempt to establish a connection.

You may set your discover setting off if you like (It is recommended that you turn it off when not using the Bluetooth). When the discover setting is off, no other Bluetooth device will be able to find it. Undiscoverable devices can still communicate with each other but they have to initiate communication themselves.
2. Bluetooth device A finds Bluetooth device B Usually the discoverable device will indicate what type of device it is (Such as a printer, cell phone, headset, etc.) and its Bluetooth device name. The Bluetooth device name is the name that you give the Bluetooth device or the factory name that originally was programmed.
3. Bluetooth Device A prompts you to enter a password (PassKey) With advanced devices (i.e. computers, smartphones), both users must agree on the Passkey and enter it into their device. The code can be anything you like as long as it is the same for both Bluetooth wireless devices.
   On other devices, such as Bluetooth headsets, the Passkey stays the same. Refer to the product’s manual for the default passkey. Most often, the default passkey is "0000".
4. Bluetooth device A sends the Passkey to Bluetooth device B

5. Bluetooth device B sends the Passkey back to Bluetooth device A
If both Passkeys are the same, a trusted pair is formed. This will happen automatically.
6. Bluetooth device A and B are now paired and able to exchange data

Bluetooth Protocol

Bluetooth technology must be examined in two separate sections in order for you to understand the entire process of how the technology works and how it is used.

• The Bluetooth protocol defines how the wireless technology works, and
• The Bluetooth Profiles describe and organize how the technology is used.

Overview of the Bluetooth Protocol

Protocol Stack

Most protocols, Bluetooth’s included, are usually layered together into “protocol stacks”, and the various tasks are split up and assigned to the different layers of protocols in the stack. Think of it like an organization or company that is located in an office building with multiple floors. The building is organized so that each floor is a different department within the company. Each department has separte duties and responsibilites, but each department is necessary for the entire organization to function as a whole.
Bluetooth's protocol has several "departments", which are referred to as levels.

Bluetooth Protocol Architecture

Bluetooth Protocol Stack

Here is an outline of the different levels in the Bluetooth protocol stack:

Radio Layer

Baseband Layer

Link Manager Protocol (LMP)

Host Controller Interface (HCI)

Logical Link Control and Adaptation Protocol (L2CAP)

RFCOMM

Service Discovery Protocol (SDP)

Also relying on L2CAP is the Service Discovery Protocol (SDP). The SDP provides a way for applications to detect which services are available and to determine the characteristics of those services.

Bluetooth Protocol

Bluetooth technology must be examined in two separate sections in order for you to understand the entire process of how the technology works and how it is used.

• The Bluetooth protocol defines how the wireless technology works, and
• The Bluetooth Profiles describe and organize how the technology is used.

Overview of the Bluetooth Protocol

Protocol Stack

Most protocols, Bluetooth’s included, are usually layered together into “protocol stacks”, and the various tasks are split up and assigned to the different layers of protocols in the stack. Think of it like an organization or company that is located in an office building with multiple floors. The building is organized so that each floor is a different department within the company. Each department has separte duties and responsibilites, but each department is necessary for the entire organization to function as a whole.
Bluetooth's protocol has several "departments", which are referred to as levels.

Bluetooth Protocol Architecture

Bluetooth Protocol Stack

Here is an outline of the different levels in the Bluetooth protocol stack:

Radio Layer

Baseband Layer

Link Manager Protocol (LMP)

Host Controller Interface (HCI)

Logical Link Control and Adaptation Protocol (L2CAP)

RFCOMM

Service Discovery Protocol (SDP)

Also relying on L2CAP is the Service Discovery Protocol (SDP). The SDP provides a way for applications to detect which services are available and to determine the characteristics of those services.