Bluetooth Simulation Developers: Eran Cohen Ran Zavhon Guide: Gil Zusman

Project Motivation BUT There are still some uncovered problems : Bluetooth scaternets are not yet fully defined. The Bluetooth scheduling algorithm. Bluetooth routing protocols. Some other problems. Bluetooth is a world wide standard and is developed by the most influencing companies in the world. In this project we will concentrate on the scheduling problem

A Little About Bluetooth Piconet : A group of 2 – 8 units connected between them, constructing a Bluetooth basic network. Scaternet : A more complex bluetooth network, built out of piconets.

Bluetooth uses a Time Division Duplex scheme : Each slot is 625usec long The master start transmitting only in even slots and slaves reply only in odd slots. Packets can be transmitted in 1,3,5 slots.

Bluetooth Stack

Bluetooth Scheduling Problem The approximately throughput in the scenario is 75%. Once a master polls a slave, the next slot is reserved for the slave irrespective of whether the slave has data to send or not.

Project Goal Simulate the Bluetooth protocol in a software environment. Check the Bluetooth scheduling methods with a numerous scheduling algorithms :  Round Robin (the method exist on BT devices today).  Exhaustive  Gated  Globally Gated  Other Priorities algorithms

Exhaustive – The master empties the buffer completely before transferring to the next slave. Gated – the same as Exhaustive but empties only the packets that were in the buffer when the master got to the slave. Globally Gated – Same as Gated but in a predefined bigger period of time. Other Priorities algorithms – Priority scheme algorithm, K-Fairness algorithm and some more ideas that will come in time.

Choosing the simulation environment we had some options :  Writing our own simulator.  Getting a commercial simulator.  Ns – An academic simulation package. We chose NS Network Simulator

NS Advantages : Has implementation of wide variety of network protocols. Powerful analysis tools. Open sourced – written in C++ and OTcl. Maintainability. Reliability. NS – Network Simulator

NS is a software package which can simulate most of the network protocols exist today and those which are in development. NS Basics

NAM – Network Animator NS Graphical User Interface

BlueHoc BlueHoc simulator provides a Bluetooth extension for the Network Simulator – NS. BlueHoc was developed in IBM research labs and released on the BlueHoc simulates a Bluetooth piconet consisting of a master and 1-7 slaves. Scatternet and mobility are not implemented yet.

The following Bluetooth layers have been simulated by BlueHoc: Bluetooth radio. Bluetooth baseband. Link Manager Protocol (LMP). Logical Link Control and Adaptation Protocol (L2CAP). A very degenerate Bluetooth Host.

Deficit Round Robin The scheduling algorithm implemented in BlueHoc. A scheduling scheme which enforces the Master to poll to every slave on a specified slot (even slots only), and the next slot is reserved for that slave irrespective of weather it has data to sent or not.

BlueHoc States Simulation ST = standby, I = inquiry, IS = inquiry scan, IR = inquiry response, P = page PS = page scan, SR = slave response, MR = master response, C = connection

Next Semester’s Work -Implementation of scheduling algorithms above BlueHoc extension for NS. - Extending the BlueHoc capabilities evolving an accurate simulation of the Bluetooth network.