blue tooth

Slide 1: 

BLUETOOTH

HISTORY OF BLUETOOTH : 

HISTORY OF BLUETOOTH Harald I Bluetooth (Danish Harald Blåtand) was the King of Denmark between 940 and 985 AD. The name "Blåtand" was probably taken from two old Danish words, 'blå' meaning dark skinned and 'tan' meaning great man. Old Harald Bluetooth united Denmark and Norway, Bluetooth of today will unite the worlds of computers and telecom In 1994 Ericsson Mobile Communications initiated a study to investigate the feasibility of a low-power low-cost radio interface between mobile phones and their accessories. In Feb 1998, five companies Ericsson, Nokia, IBM, Toshiba and Intel formed a Special Interest Group (SIG).

RANGE OF BLUETOOTH : 

RANGE OF BLUETOOTH Most Bluetooth devices are described as 'Class 2'. These are very low power (typically 1 milliwatt - 1/1000th of a watt) and have a range of about 10 m (33 ft). Some devices - for example, some plug in 'dongles' that can be added to to laptop computers - are Class 1. These have range comparable to that of Wi-Fi, ie, 100 m or 330 ft. With Bluetooth, short range is actually a benefit, because it reduces the chance of interference between your Bluetooth devices and those belonging to other people nearby.

BLUETOOTH AND PICONET : 

BLUETOOTH AND PICONET Bluetooth devices can interact with one or more other Bluetooth devices in several different ways. The simplest scheme is when only two devices are involved. This is referred to as point-to-point. One of the devices acts as the master and the other as a slave. This ad-hoc network is referred to as a piconet. As a matter of fact, a piconet is any such Bluetooth network with one master and one or more slaves. In the case of multiple slaves, the communication topology is referred to as point-to-multipoint. In this case, the channel (and bandwidth) is shared among all the devices in the piconet. There can be up to seven active slaves in a piconet. Each of the active slaves has an assigned 3-bit Active Member address (AM_ADDR). There can be additional slaves which remain synchronized to the master, but do not have a Active Member address. These slaves are not active and are referred to as parked. For the case of both active and parked units, all channel access is regulated by the master. A parked device has an 8-bit Parked Member Address (PM_ADDR), thus limiting the number of parked members to 256. A parked device remains synchronized to the master clock and can very quickly become active and begin communicating in the piconet.

Slide 5: 

PICONET DIAGRAM

BLUETOOTH AND SCATTERNET : 

BLUETOOTH AND SCATTERNET If two piconets were within the same coverage area. For example, you might have a piconet consisting of your cell phone and your PC, while the person in the neighboring cubicle has a piconet consisting of a cell phone, headset, and business card scanner. Because the two piconets are so close, they have overlapping coverage areas. This scenario is provided for in the Bluetooth specification and is referred to as a scatternet. As a matter of fact, slaves in one piconet can participate in another piconet as either a master or slave. This is accomplished through time division multiplexing. In a scatternet, the two (or more) piconets are not synchronized in either time or frequency. Each of the piconets operates in its own frequency hopping channel while any devices in multiple piconets participate at the appropriate time via time division multiplexing. Returning to the example, you may want to set up your neighbor’s business card scanner to also transmit the information that is scanned to your PC so that you will have access to his business contacts information. Of course, this would have to be a mutually agreed upon usage.

SCATTERNET DIAGRAM : 

SCATTERNET DIAGRAM

DEVICES THAT USE BLUETOOTH : 

DEVICES THAT USE BLUETOOTH Digital cameras and camcorders Printers Scanners Cell Phones PDAs Laptops Keyboards and Mice Headsets In-car handsfree kits GPS navigation receivers Home appliances (microwaves, washers, driers, refrigerators)

BLUETOOTH AND INTERNET : 

BLUETOOTH AND INTERNET Bluetooth can be used to connect between a device that has internet connectivity and another device that does not, for example, you might use Bluetooth to connect from your PDA to your laptop, and then your laptop might use Wi-Fi to connect to a Wi-Fi router and from there you would be connected to the internet. A much better approach might be to get Bluetooth on your PDA and also on your cellphone and use Bluetooth to connect to your cellphone and then connect through your cellphone and out to the internet from there. eg:T-Mobile's GPRS service offer unlimited connect time and unlimited bandwidth usage .

BLUETOOTH Vs WI-FI : 

BLUETOOTH Vs WI-FI Wi-Fi is primarily used as an alternate to traditional cable based networks. It has a longer range than Bluetooth, and supports faster data transfer and so it might seem better than bluetooth. But, in reality, Bluetooth and Wi-Fi have different purposes. Bluetooth is intended for limited data transfer between many different types of devices, Wi-Fi is more focussed on faster data transfer between computers on a network. One of the distinctive elements of Bluetooth is that is uses very much less power than Wi-Fi. Class 2 devices (such as are in PDAs, phones, headsets, etc) transmit a very low power signal (1 mW) and only transmit intermittently when in standby mode, saving even more power. Wi-Fi, on the other hand, consumes a great deal of power, and so for any type of portable battery operated device, Bluetooth will allow for substantially more battery life than would Wi-Fi. If you're simply wanting to swap data between different devices in your office and elsewhere on a casual and occasional basis, then - assuming that the software and bluetooth hardware is available,then bluetooth is probably a better choice. If you need more range, and higher bandwidth; perhaps if you want to connect computers into your office LAN, then Wi-Fi is a better choice for you

BLUEJACKING : 

BLUEJACKING Bluejacking is a moderately harmless 'fun' type trick that some people have discovered. It involves sending messages from your Bluetooth device to other people close to you with bluetooth devices and surprising the recipients. The easiest way to Bluejack is to create a new phonebook contact, with the message you want to send in the name field. Then, in a busy place with lots of people (so that there is a chance that someone might have a Bluetooth enabled phone or PDA), choose the option to send your new contact via Bluetooth. Your phone or PDA will then search for all Bluetooth devices in range, and present you with a list. Choose whichever device you wish from the list and send it. The recipient will get a message asking if they wish to accept your contact, and showing the text you entered as the contact's name (eg: something like 'Bad weather today isn't it' or whatever else you wish to say). If you're planning to enjoy Bluejacking (or Toothing, below) you'll probably want to get your eye in to guessing how far away 10 m/33 ft is so as to know how many people and devices might be within range.

FUTURE OF BLUETOOTH : 

FUTURE OF BLUETOOTH

Bluetooth Conclusions : 

Bluetooth Conclusions Bluetooth is a uniquely positioned wireless solution Focused primarily on short range Targets modest but acceptable performance Can operate at very low power Has lots of utility designed in Support for voice and data Personal Area Networking Roaming Complex topologies Features a very robust protocol And targeted at HIGH VOLUME applications!!!