UCBT - Bluetooth extension for NS2 at the University of Cincinnati

1. Introduction

Bluetooth is a low power, low cost, short range radio network standard and is complementary to the Wi-Fi network specified by IEEE 802.11b/g/a standard. Bluetooth uses a frequency hopping scheme to provide robust wireless communication. As a cable replacement, Bluetooth is widely used in cell phone, PDA, laptop, headset, printer, etc. to form a Personal Area Network (PAN) and provide universal access.

UCBT (stands for University of Cincinnati - BlueTooth) is a ns-2 based Bluetooth network module which simulates the Bluetooth network operations in great details. Most specifications at Baseband and above like LMP, L2CAP, BNEP have been simulated in UCBT, including frequency hopping scheme, device discovery, connection set up, Hold, Sniff and Park modes management, role switch and multi-slot packet type negotiation, SCO voice connection, etc. There is a provision to constitute a cluster of Bluetooth devices and such formation with up to 8 Bluetooth devices is known as a piconet. It also allows a number of piconets to be connected together using "bridge nodes" and such a large network is usually referred to as a scatternet.

UCBT is not the first ns-2 based Bluetooth simulator. BlueHoc developed at IBM and its scatternet extension, Blueware at MIT, both pre-date UCBT. However, with 28,000+ lines of C++ code, UCBT is the most accurate, complete and up-to-date open-source Bluetooth simulator. UCBT adapts to the PAN profile with Bluetooth Network Encapsulation Protocol (BNEP). UCBT takes clock drift into account, which is very important for simulating synchronization or scheduling protocols accurately, as difference devices will drift apart in long period. UCBT also includes the newly adopted Enhanced Data Rate (EDR) specification to simulate new devices with 2 or 3 Mbps data rate. One of our main contributions is that UCBT provides a flexible framework to conduct Bluetooth scatternet research. A scatternet requires time sharing of some common devices (bridges) among piconets. Coordination of the presence schedule of bridge nodes in a large mesh scatternet is very challenging. UCBT provides multiple bridge scheduling algorithms to enable scatternets to operate smoothly. Prototype self-organized scatternets are being designed and simulated.

2. Functionality

As a bluetooth module for ns-2, UCBT implements a full bluetooth stack, including Baseband, LMP, L2CAP, BNEP layers. It integrates with ns-2 well and works out of box for recent ns-2 release, ns-2.28. UCBT closely follows spec 1.1 and is partially updated to spec 2.0.
bluetooth stack BTNode

3. Availability

A development version is available for download. If you think this software is useful, please drop me a line or write to Dr. Agrawal so that my thesis committee will know that I'm doing something meaningful.

4. People

5. Support