BlueTooth HighLevel Simulator

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BlueTooth High-Level Simulator

• A Base Platform For Simulating Packets Routing
  Algorithms Over A Bluetooth Scatternet

Students Ehud Klugman klugman_at_internet-zahav.n
et Eitan Peri eitanp_at_barak-online.net Instruc
tor Ran Cohen
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BlueTooth Background

• BlueTooth is a technology specification.
• It describes how various electronic products, can
  interconnect with each other using a short-range
  wireless connection, and establish a network.
• Some BlueTooth basic terms
• Unit - The most primitive element in a BlueTooth
  scatternet. It can be any electronic product
  which implements the BlueTooth specification. At
  a single piconet, a unit can be a master unit or
  a slave unit.
• Piconet - A mini-network, with small coverage
  area, which consist of one BlueTooth master unit,
  and one to seven slave units. Slaves communicate
  only with the master unit (and not with each
  other).

• Scatternet - Group of piconets with overlapping
  area of coverage. A unit can act as master
  slave at the same time in different piconets or
  as slave in those piconets. It is possible to
  route packets in a scatternet.

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Project Objectives

• Base platform for simulating routing algorithms
  over a scatternet.
• Simulates connecting/disconnecting of units to
  the scatternet over the time axis.
• The behavior of the unit is pre-defined by the
  user using different attributes.
• Supporting run-time tracing over units
  connectivity to the scatternet.
• User Interference during run-time, can be used to
  connect/disconnect units form the piconet or the
  scatternet.

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Our Implementation - General

• Language Java.
• Code can run on any platform.
• Ready classes for networking and threads.
• Each unit is represented by a separate process.
• Our code implements a single unit, which can be
  executed from the command prompt.
• Running a few units simultaneously, can create a
  piconet/ scatternet.
• The units communicate over the network using UDP
• UDP is best for simulation radio transmissions.
• Units can run on different machines.
• Packets loss is simulated in application level.
• Acknowledge is needed for every packet
  transmissions (except broadcast SCO
  connection), and is implemented in application
  level.

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Our Implementation General (cont.)

• Packets enumerating is used to distinguish
  packets
• Avoiding duplicated packets/ack. to be executed
  more then once.
• Use Responses Cache in order to save
  re-calculating a certain response, when
  duplicating request is received.
• Running the simulation can be done through
  script
• Scripts Contain some attributes for each unit, in
  a single line.
• It executes the processes/units one by one.
• Command-line user interface can be used to
  change/see units attributes on run time
• Changing the roles of a unit, means connecting
  disconnecting it from a specific piconet, or
  destroying it completely.
• Seeing the units connectivity, and other
  information.

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High Level Design Classes Relations
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High Level Design Main Classes Description

• BTudpConnection - A single network connection.
• BTrecv - Inherited from thread class, and handles
  received massages from the network. There are two
  kind of received massages
• Request - Contain a certain command that should
  be handled by the receiving unit. For example, a
  request from new slave unit to the piconets
  master to be added to this piconet.
• Response Contains the result of executing
  previous Request. There are two kinds of
  responses
• Immediate response Indicates that the request
  and was received, and the receiving unit started
  to process it. It is sent when the processing
  time of the request might be long.
• Final replay Indicates that the receiving unit
  finished processing the request, and contains the
  requested data. As in the example above, the
  master can replay to the new unit with its
  identification number in the piconet or by
  denying the request
• BTrequestsTable - Implements a table, that
  contains requests that were sent on the network,
  but no acknowledgements were received for them.

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High Level Design Main Classes Description
(continue)

• BTresponseCache - Caching implementation of the
  responses that the unit is sending to other
  units
• When a request from the unit is received at the
  first time
• It is passed to BTunitFuncManager that generates
  a response.
• The response is stored in the data structure of
  this class.
• If this request is received again (response was
  lost)
• Its response is stored in the cache of receiving
  unit (BTrecv).
• The response is read from the cache, and is send
  immediately. The time of computing the response
  again is saved.
• BTmsgSendQueue - Implements a queue of massages
  that should to be sent
• BTrecv BTunitFunc classes fill this queue with
  massages.
• BTsend, which run on separate thread, fetches
  the massages that is located on the top of this
  queue, and send them.
• BTsend -Inherited from thread class, and has two
  tasks
•  Sends to network the massages that are in
  BTmsgSendQueue. Each sent massage is also added
  to BTrequestsQueue.
• Re-send requests that werent acknowledged by the
  destination unit after a certain time (using
  BTrequestsQueue).

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High Level Design Main Classes Description
(continue)

•  BTunitFunc - Represents a single functionality
  of the unit in the Bluetooth scatternet.
• Such a functionality is either master or a slave
  in a single piconet.
• A unit can own more than one BTunitFunc, if it is
  in a few piconets.
• Those two functionalities are inherited from this
  class.
• BTunitFuncManager - Responsible for the
  following
• Create a new BTunitFunc, or destroy an existing
  one.
• Creation or destruction of BTunitFunc is done,
  when a command is passed to this class from
  BTscheduler or BTuserInterface classes.
• Receive massages from BTrecv and deliver them to
  the right BTunitFunctional object.  
• BTuserInterface - Inherited from thread class,
  has the following tasks
• Display units information to the user on screen.
• Receive from the user some basic commands.
• BTscheduler - It is the main stream of the unit,
  has two main tasks
• Create all other objects on proccess
  initialization.
• Schedule the creation and the destruction of
  BTunitFunc classes, by using functions of
  BTunitFuncManager