Bluetooth Technology: The World Goes Wireless
Bluetooth Networking: V.I.P. only
Bluetooth enabled devices; regardless of the generation they were born in, can exchange information over a Bluetooth exclusive network called a Piconet. When a Bluetooth enabled device comes within range of another enabled device (about 35 feet) or is just turned on, it sends out radio signals in the range of 2.402 GHz and 2.480 GHz, broadcasting its preprogrammed address that falls into a range of addresses it has established for a particular type of device, any other devices which are not connected to another Piconet is asked to join with the device and now a new Piconet is formed.
Once the networks are established, the systems begin talking among themselves. Each Piconet hops randomly through the available frequencies, so all of the piconets are completely separated from one another. For example, if you are streaming music from your Bluetooth computer to your Bluetooth headphones, your cell phone and newly paired wireless hands free device will not interfere with each other. A Bluetooth Piconet jumps through the established frequency range about 1600 times a second to avoid interfering with other networks on the same slice of frequency. So even if your Piconets do interfere with each other, the disturbance will persist for few rough Nano seconds and wouldn’t disrupt the whole network long enough to compromise its integrity. The utility of the frequency hopping is profound not only to quell disturbances between piconets but to minimize interference from any other devices on the 2.4 to 2.48 band. This band is officially deemed the International Scientific and Medical Device Band (ISM) and includes (obviously) medical devices, cordless phones, baby monitors, garage door openers and other devices too numerous to name here. So you’re Bluetooth stereo wont interfere with your grandpa’s pacemaker long enough to send him to the emergency room.
Bluetooth is a Sadomasochist:
You and your five friends get into your car and the trusted Magellan 6000t Gps is waiting for you with a listing of phones it has under its control. You’re the driver so you select “My Phone” from a screen of willing victims the Gps wants to have dominion over and you start making calls from the Gps.
This scenario is a demonstration of the “master” and “slave” networking concept of one master and up to seven slaves inside the Piconet. In newer versions of Bluetooth an additional 255 slave devices can be inactive, or parked, which the master can summon up our will. At any time, data can be transferred between master and slave at the max rate of three megabytes per second. Master and slave role is not a one way street; the role can be switched and often is. In the future (one year from now) Bluetooth specs will allow connection between 2 or more piconets to form a mega Piconet called a scatternet, with some devices acting as a bridge by simultaneously playing the master role in one Piconet and the slave role in another Piconet. This would enable the transfer of data to go unprecedented distances, well over the maximum 35 feet (for class two devices).
Bluetooth Security Features:
Those who send information over wireless radio signals must have extra precautions in place to prevent any nay Sayers from interrupting our transmissions and giving our components viruses or even worse, ads. Since Bluetooth technology is wireless and therefore susceptible to spying and remote access in the way your wifi is not very secure off the bat. The automatic nature of the connection, which is a huge benefit in terms of time and effort, is also a benefit to people looking to send you data without your permission.
Bluetooth offers several security modes:
Security Mode 1: non-secure
Security Mode 2: service level enforced security
Security Mode 3: link level enforced security
Device manufacturers determine which mode to include in a Bluetooth-enabled gadget. In almost all cases, Bluetooth users can establish “trusted devices” that can exchange data without asking permission. When any other device tries to establish a connection to user’s device, the user has to decide to allow it. Service-level security and device-level security work in conjunction to protect Bluetooth devices from unauthorized data transmission. Security methods include authorization and id procedures, limiting the use of Bluetooth services to the registered user and require that owner to make a conscious decision (usually press yes) to open a file or authorize a data transfer. As long as these measures are enabled on the user’s phone or other device, unauthorized access is unlikely. A user can also simply switch his Bluetooth mode to “non-discoverable” and avoid connecting with other Bluetooth devices completely. If a user makes use of the Bluetooth network primarily for synching devices at home this mode is best when using devices in public.
Other problems like “bluejacking”, “bluebugging” and “Car Whisperer” have turned up as Bluetooth-specific security issues. Bluejacking involves Bluetooth users sending a business card (just a text message, really) to other Bluetooth users within a 10-meter (32-foot) radius. If the user doesn’t realize what the message is, he might allow the contact to be added to his address book, and the contact can send him messages that might be automatically opened because they’re coming from a known contact.
Bluebugging is more of a problem, because it allows hackers to remotely access a user’s phone and use its features, including placing calls and sending text messages, and the user doesn’t realize its happening.
The Car Whisperer is a piece of software that allows hackers to send audio to and receive audio from a Bluetooth-enabled car stereo. Device manufacturers are constantly evolving their firmware to stay in competition with these new security breaches. The #1 advice that I give you in regards to maintaining your security and consequently your sanity is to always set your devices to non discoverable, never accept downloads via text messages from people you know and turn off the Bluetooth in your phone when it is not in use.
Aside from the security breaches propagated by evil techno junkies and inane electronic advertising, which are inevitabilities of new technologies, Blue tooth has the ability to change the way you work, play, sleep, and maybe even eat.
Stay tuned for my next article on new wireless products and what you can do with them.