DABC

The discussions about DAQ systems for FAIR experiments started in 2004 supported by the FutureDAQ project. As a most challenging experiment, CBM requirements were a driving force for new concepts. The main idea was to investigate, if it is possible to switch a highly parallel, self-triggered, time stamped data stream of upto one TB/s over standard networks. Event definition, building, and filtering would then be done on compute farms, eventually utilizing special purpose CPUs. Detailed simulations and real tests (on InfiniBand clusters) of event building over networks had been performed.
In 2006 the need of a demonstrator came up. At the other hand, the current MBS DAQ systems with their huge installed hardware base (about 100 installed, 50% outside GSI) must be integrated in any new DAQ concept. Therefore the support of MBS frontends was added to the use cases.

Use cases

• Detector tests
• FE equipment tests
• Data transport
• Time distribution
• Switched event building
• Software evaluation
• MBS event builder
• General purpose DAQ backbone

Requirements

• build events over fast networks
• handle triggered or trigger less front-ends
• process time stamped data streams
• provide data flow control (to front-ends)
• connect (nearly) any front-ends
• provide interfaces to plug in application codes
• connect MBS readout or collector nodes
• be controllable by several controls frameworks

-- HansEssel - 12 Nov 2007