Decibel

service architecture for multi-media based communication

The aim of this initial project --which started off under the name OpenCDI-- is to create a platform independent telephony framework for the implementation of Computer Telephony Integration (CTI) and telephony applications. It provides a simple method to access conventional PSTN hardware as well as IP telephony setups. The applications use Decibel as a desktop service interface. Thus it represents the interface to local communication middleware.

The main infrastructure of Decibel will be implemented with libraries that are part of the upcoming LSB 3 standard and that are available on other platforms like Windows and Linux Embedded as well. This includes libraries such as {\tt libstdc++}, glib, and Qt.

Decibel sits on top of the Tapioca framework, which will provide the basic communication interfaces and protocol implementations. Tapioca is the implementation of the Telepathy architecture, which defines the DBUS protocol specification for integrating various components. This assures interoperability between platforms.

We intend to create a framework that sits on top of the Tapioca API; to share communities and to work together. The use of the existing IPC specification enables the use of existing Tapioca backends. Where necessary, we will extend the existing framework and specifications and discuss this with the community.

The communication protocol used by the applications will be DBUS, using the protocol specification provided by the Tapioca project. The architecture of the framework will consist of a plugin structure which can be extended easily. These plugins (called backends) provide resource services which are handled by the service manager. One of them will provide an adapter which accesses PBX systems (CTI 3rd party control). Others contain a softphone implementation (CTI 1st party control) or a remote control of a hardphone (CTI 1st party control). Additional backends will provide services for audio subsystems, audio codecs, video codecs, media protocols, etc. The backend interfaces will be discussed with the Tapioca project, so that we can make sure Tapioca backends work with Decibel and vice versa.

Decibel will be independent to any desktop environment, but the first proof of concept implementation will be integrated into the KDE- Desktop environment to show its power and flexibility.