| Blue tooth devices will usually function at 2.4 | | | | 3. Gives a base level of security asit's extremely |
| GHZin the license free, globally accessible ISM | | | | onerous for an eavesdropping system to |
| radioband. The advantage to this band consists | | | | predictwhich frequency the blue tooth units will |
| of worldwideavailability and compatibility. A | | | | usenext. |
| disadvantage tothis however, is that the gadgets | | | | The connected units nonetheless, should agree |
| should share thisband with different RF emitters. | | | | upon thefrequency they will use next. The |
| This may includecar security systems, other | | | | specificationin blue tooth ensures this in two |
| wireless units,and different noise sources, such as | | | | ways. First, itdefines a master and slave type |
| microwaves. | | | | relationship betweenbluetooth devices. Next, it |
| To beat this challenge, Bluetooth technology uses | | | | specifies an algorithmthat makes use of system |
| aquick frequency hopping design and subsequently | | | | particular data whencalculating the frequency hop |
| usessmaller packets than other standards within | | | | sequences. |
| the | | | | A blue tooth device that operates in master |
| ISM band. This design will help to make | | | | mode cancommunicate with as much as seven |
| bluetoothcommunication extra robust and extra | | | | devices that are set inslave mode. To each of |
| secure. | | | | the slaves, the masterblue tooth device will send |
| Frequency Hopping | | | | its own distinctive addressand the value of its |
| Frequency hopping is principally leaping from | | | | personal inner clock. Thedata despatched is then |
| frequencyto frequency within the ISM radio | | | | used to calculate thefrequency hop sequences. |
| band. After ablue tooth system sends or | | | | Because the master system and every of the |
| receives a packet, itand the machine (or units) it | | | | slavedevices use the same algorithm with the |
| is communicating withhop to a different frequency | | | | same preliminaryinput, the related units will always |
| before the next packet issent. This system | | | | arrivetogether on the next frequency that |
| offers three advantages: | | | | they've agreedupon. |
| 1. Permits bluetooth gadgets to use theentirety | | | | As a replacement for cable technology, it is |
| of the accessible ISM band, while | | | | nosurprise that bluetooth devices are often |
| nevertransmitting from a fixed frequency for | | | | batterypowered, such as wi-fi mice and battery |
| more than aquick interval of time. This helps | | | | poweredcell phones. To preserve the power, |
| insure thatblue tooth conforms to the ISM | | | | most devicesfunction in low power. This helps to |
| restrictions on thetransmission amount per | | | | provide bluetoothdevices a range of around 5 - 10 |
| frequency. | | | | meters. |
| 2. Makes sure that any interference won'tlast | | | | This range is far enough for wi-fi |
| long. Any packet that does not arrive safelyto | | | | communicationhowever close enough to avoid |
| its destination may be resent to the | | | | drawing an excessive amount of powerfrom the |
| nextfrequency. | | | | power source of the device. |