Bluetooth (A Distributed System Perspective)

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Bluetooth(A Distributed System Perspective)

• CS-775/875 Presentation
• By
• Jerry Garcia
• jgarcia_at_cs.odu.edu
• September 29, 2003

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Outline

• Introduction
• Concept
• Operation
• History
• Architecture
• Hardware
• Specifications
• Protocol Stack
• Network
• Software
• Discovery Services
• State Machine
• APIs (Windows/JAVA)
• Distributed System Issues
• Heterogeneity
• Openness
• Security
• Scalability
• Failure Handling

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Concept and Operation

• Bluetooth is a
• low-cost and low power consumption wireless
  industry-standard protocol that enables wireless
  connectivity for a multitude of devices such as
  computers, mobile phones, handheld devices, cars,
  smart appliances, home entertainment system,
  heating/cooling systems and many others devices.
  
• enables users to control, transfer and
  synchronize data without having to cable devices
  together, merely by having the devices come
  within range (30 to 100 meters) of each other.

Figure 1 Voice/data access points
Figure 2 Peripheral interconnects
Figure 3 Personal Area Networking (PAN)
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History

• In 1997, Ericsson and Intel invented the concept
  of Bluetooth. It was named after 10th Century
  Viking King Harald Blätand (Bluetooth). King
  Blätand joined two Scandinavian kingdoms
  peacefully.
• Today, Bluetooth 2.0 work is on going. Promoter
  companies 3Com, Ericsson, IBM, Intel, Lucent
  Technologies, Microsoft, Motorola, Nokia and
  Toshiba.

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Bluetooth Specifications and Architecture
Radio Frequency Frequency Hopping across the ISM Band (2.5GHz)
Connections Simultaneously supports both data (Asynchronous connectionless) links and voice (Synchronous connection-oriented) links features. Support up to seven simultaneous connections.
Data Rates Voice - 64 kb/s, Data 723.2 kb/s
Distance 10 meters to 100meter (if transmitters power is increased)
Cost Less than 10 per module (100 per for HomeRF and IEEE 802.11)
Figure-2 Bluetooth Specification Protocol Stack
Table-1 Bluetooth Specifications
Figure-1 Bluetooth Module
Figure-3 Host Controller Interface (HCI)
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Bluetooth Distributed System Model(Spontaneous
Networking)

• Key Features of a Spontaneous Network
• Easy connection (no cabling and transparently
  reconfigured).
• Easy integration with local services (devices
  discover automatically what services are provided
  in this network to the user).

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Service Discovery

• Service Discovery Protocol (SDP) is a packet
  based protocol utilizing a request-response
  architecture. It provides a means of determining
  what Bluetooth services are available on a
  particular device via searching (based on UUID
  for a specific capability) or browsing (directory
  of device services).

SDP Client
SDP query requests information about services
SDP provides no notification mechanism to
indicate that an SDP server, or any specific
service, has become available or unavailable as
may occur when the services available on a device
change, or when a device comes in or out of RF
proximity.

• SDP Server
• Maintains Services Catalog
• Provides information.
• Perform an action
• Control a resource

SDP Client
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Logical Link Control and Adaptation Protocol
(L2CAP) State Machine
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Bluetooth APIs

• Microsoft based API
• Functions
• Interfaces
• Security
• JAVA based API JSR 82
• http//wireless.java.sun.com/midp/articles/bluetoo
  th1/
• http//wireless.java.sun.com/midp/articles/bluetoo
  th2/

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Distributed System Issues
Attributes Pro Cons
Heterogeneity Bluetooth component can reside on all types of systems. All systems must have Bluetooth compliant component.
Openness Standards are in place.
Security Trusts are established. Certificates are exchanged between devices. Encryption is used If a devices is also used as a gateway to other networks, then the security is compromised.
Scalability Supports both Voice and Data. Limited bandwidth and Limited number of participates in a piconet.
Failure Handling No callback mechanism, client polling required.
Concurrency Max of 7 devices simultaneously within a PAN.
Transparency Various APIs are available.
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Applying the Bluetooth Technologyto the
Spaceflight Domain

• Designing for spaceflight one must consider
  the following
• Safety
• Size
• Weight
• Power consumption
• EMI/EMC
• Reliability

• Bluetooth Applications
• Space Shuttle Tile Identification
• Experimental Instrument
• Communication Interface

April 12, 1981, STS-1 First Space Shuttle,
Columbia
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References

• www.ericsson.com/bluetooth
• www.bluetooth.com
• www.intel.com
• http//msdn.microsoft.com search for Bluetooth
• http//www.palowireless.com/infotooth
• Bluetooth architecture, protocol and
  applications, Song-Joo, Goh, International IC-
  China, Conference Proceedings
• Specification of the Bluetooth System Core,
  Specification Volume 1.0B, Dec. 1999
• Embedded Systems Programming, Internet Appliance
  Design, Bluetooth Basics, Rebecca Spaker,
  www.embedded.com/internet/0007/0007ia1.htm
• Distributed Systems Concepts and Design, G.
  Coulouris J. Dollimore, T. Kindberg, 3rd Edition,
  2001.
• http//wireless.java.sun.com