14-11-2012, 05:28 PM
Bluetooth Technology
Bluetooth.ppt (Size: 1.09 MB / Downloads: 101)
Bluetooth Protocol Stack
Composed of protocols to allow Bluetooth devices to locate each other and to create, configure and manage both physical and logical links that allow higher layer protocols and applications to pass data through these transport protocols
Transport Protocol Group
Radio Frequency (RF)
Sending and receiving modulated bit streams
Baseband
Defines the timing, framing
Flow control on the link.
Link Manager
Managing the connection states.
Enforcing Fairness among slaves.
Power Management
Logical Link Control &Adaptation Protocol
Handles multiplexing of higher level protocols
Segmentation & reassembly of large packets
Device discovery & QoS
Middleware Protocol Group
Additional transport protocols to allow existing and new applications to operate over Bluetooth. Packet based telephony control signaling protocol also present. Also includes Service Discovery Protocol.
Master - Slave
Master
Device in Piconet whose clock and hopping sequence are used to synchronize all other devices (slaves) in the Piconet.
It also carries out Paging procedure and also Connection Establishment.
Slaves
Units within the piconet that are syncronized to the master via its clock and hopping sequence.
After connetion establishment, Slaves are assigned a temporary 3 bit member address to reduce the no. of addresing bits required
Physical Link Types
Synchronous Connection Oriented (SCO)
Point to Point Full Duplex between Master & Slave
Established once by master & kept alive till released by Master
Typically used for Voice connection ( to guarantee continuity )
Master reserves slots used for SCO link on the channel to preserve time sensitive information
Asynchronous Connection Link (ACL)
It is a momentary link between master and slave.
No slots are reserved.
It is a Point to Multipoint connection.
Symmetric & Asymmetric links possible
Power Control Modes
Sniff Mode
This is a low power mode in which the listening activity of the slave is reduced.
In the sniff mode, the slave listens for transmissions only at fixed intervals Tsniff, at the offset slot Dsniff for Nsniff times. These parameters are given by the LMP in the master when it issues the SNIFF command to the slave.
Hold Mode
Slave temporarily (for Thold sec) does not support ACL packets on the channel (possible SCO links will still be supported).
By this capacity can be made free to do other things like scanning, paging, inquiring, or attending another piconet.
The slave unit keeps its active member address (AM_ADDR).
Bluetooth.ppt (Size: 1.09 MB / Downloads: 101)
Bluetooth Protocol Stack
Composed of protocols to allow Bluetooth devices to locate each other and to create, configure and manage both physical and logical links that allow higher layer protocols and applications to pass data through these transport protocols
Transport Protocol Group
Radio Frequency (RF)
Sending and receiving modulated bit streams
Baseband
Defines the timing, framing
Flow control on the link.
Link Manager
Managing the connection states.
Enforcing Fairness among slaves.
Power Management
Logical Link Control &Adaptation Protocol
Handles multiplexing of higher level protocols
Segmentation & reassembly of large packets
Device discovery & QoS
Middleware Protocol Group
Additional transport protocols to allow existing and new applications to operate over Bluetooth. Packet based telephony control signaling protocol also present. Also includes Service Discovery Protocol.
Master - Slave
Master
Device in Piconet whose clock and hopping sequence are used to synchronize all other devices (slaves) in the Piconet.
It also carries out Paging procedure and also Connection Establishment.
Slaves
Units within the piconet that are syncronized to the master via its clock and hopping sequence.
After connetion establishment, Slaves are assigned a temporary 3 bit member address to reduce the no. of addresing bits required
Physical Link Types
Synchronous Connection Oriented (SCO)
Point to Point Full Duplex between Master & Slave
Established once by master & kept alive till released by Master
Typically used for Voice connection ( to guarantee continuity )
Master reserves slots used for SCO link on the channel to preserve time sensitive information
Asynchronous Connection Link (ACL)
It is a momentary link between master and slave.
No slots are reserved.
It is a Point to Multipoint connection.
Symmetric & Asymmetric links possible
Power Control Modes
Sniff Mode
This is a low power mode in which the listening activity of the slave is reduced.
In the sniff mode, the slave listens for transmissions only at fixed intervals Tsniff, at the offset slot Dsniff for Nsniff times. These parameters are given by the LMP in the master when it issues the SNIFF command to the slave.
Hold Mode
Slave temporarily (for Thold sec) does not support ACL packets on the channel (possible SCO links will still be supported).
By this capacity can be made free to do other things like scanning, paging, inquiring, or attending another piconet.
The slave unit keeps its active member address (AM_ADDR).