The JSR82ext Stack for Bluetooth Audio Streaming Applications

Paolo Bellavista

University of Bologna

Cesare Stefanelli

University of Ferrara

Mauro Tortonesi

University of Ferrara

Abstract

JSR82ext (formerly known as JSR82+SCO) is an extension to the ubiQoS project to support the last-meter Bluetooth-based connection for QoS-enabled audio streaming services.


Table of Contents

1. The Bluetooth Protocol
2. The JSR82ext Architecture
3. Support for ACL links
4. Support for SCO links
5. Support for ASB links
6. Download
7. Links

1. The Bluetooth Protocol

Bluetooth is an emerging technology in the wireless world and has become the de-facto standard solution for PAN applications. Bluetooth supports two main classes of traffic: unframed data traffic, with guaranteed QoS requirements, and framed data traffic, with best-effort or guaranteed QoS.

Unframed data traffic is carried over SCO and eSCO baseband links, which are point-to-point bi-directional, symmetrical (eSCO links can also be asymmetrical), isochronous, and have a constant bit-rate (the bit-rate is fixed to 64 Kbps for SCO and user-defined for eSCO).

Framed data traffic, instead, is carried over ACL and ASB links. ACL links are bi-directional, connection-oriented, asynchronous or isochronous, and support the specification of QoS settings to indicate the desiderata for the delivery of the data frames. ASB links are connection-less links for broadcasting traffic from the master to all the slaves in the piconet. The ASB-based transmission is best-effort, with no possibility of QoS management.