comnet.technion.ac.il/~cn23s00 Computer Networks Laborator y Technion Israel Institute of Technology BlueTooth High-Level Simulator A Base Platform For Simulating Packets Routing Algorithms Over A Bluetooth Scatternet Students: Ehud Eitan Instructor : Ran Cohen

BlueTooth High Level Simulator , ZLE Strategy summary 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. 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 o ne BlueTooth master unit, and o ne to seven slave units. Slaves communicate only with the master unit (and not with each other). Piconet - A “mini-network”, with small coverage area, which consist of o ne BlueTooth master unit, and o ne to seven slave units. Slaves communicate only with the master unit (and not with each other). A BlueTooth Scatternet 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. 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.

BlueTooth High Level Simulator , ZLE Strategy summary 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 unit’s connectivity to the scatternet.  User Interference during run-time, can be used to connect/disconnect units form the piconet or the scatternet.

BlueTooth High Level Simulator , ZLE Strategy summary Our Implementation - General  Language: Java. Code can run on any platform. Code can run on any platform. Ready classes for networking and threads. 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. Our code implements a single unit, which can be executed from the command prompt. Running a few units simultaneously, can create a piconet/ scatternet. 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. UDP is best for simulation radio transmissions. Units can run on different machines. Units can run on different machines. Packets loss is simulated in application level. Packets loss is simulated in application level.  Acknowledge is needed for every packet transmissions (except broadcast & SCO connection), and is implemented in application level.

BlueTooth High Level Simulator , ZLE Strategy summary  Packets enumerating is used to distinguish packets: Avoiding duplicated packets/ack. to be executed more then once. 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. 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. Scripts Contain some attributes for each unit, in a single line. It executes the processes/units one by one. 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. 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. Seeing the units connectivity, and other information. Our Implementation – General (cont.) Script Line Example: Btsim -master if Role of the unit Executable Name Role’s start time IP address of this role Use user interface Role’s end time Port number of this role

BlueTooth High Level Simulator , ZLE Strategy summary High Level Design – Classes Relations BT_sendBT_requestsTableBT_msgSendQueueBT_recv BT_udpConnection BT_responseCache BT_unitFuncManager BT_unitFunc 1 N SlaveMaster Inherited BT_scheduler BT_userInterface

BlueTooth High Level Simulator , ZLE Strategy summary 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 piconet’s master to be added to this piconet. Request - Contain a certain command that should be handled by the receiving unit. For example, a request from new slave unit to the piconet’s master to be added to this piconet. Response – Contains the result of executing previous Request. There are two kinds of responses: 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.

BlueTooth High Level Simulator , ZLE Strategy summary 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: 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): 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. 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’, 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. Sends to network the massages that are in BTmsgSendQueue. Each sent massage is also added to BTrequestsQueue. Re-send requests that weren’t acknowledged by the destination unit after a certain time (using BTrequestsQueue). Re-send requests that weren’t acknowledged by the destination unit after a certain time (using BTrequestsQueue).

BlueTooth High Level Simulator , ZLE Strategy summary 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. 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. A unit can own more than one BTunitFunc, if it is in a few piconets. Those two functionalities are inherited from this class. Those two functionalities are inherited from this class.  BTunitFuncManager - Responsible for the following: Create a new BTunitFunc, or destroy an existing one. 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. Receive massages from BTrecv and deliver them to the right BTunitFunctional object.  BTuserInterface - Inherited from thread class, & has the following tasks: Display unit’s information to the user on screen. Display unit’s information to the user on screen. Receive from the user some basic commands. 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. Create all other objects on proccess initialization. Schedule the creation and the destruction of BTunitFunc classes, by using functions of BTunitFuncManager Schedule the creation and the destruction of BTunitFunc classes, by using functions of BTunitFuncManager