Unified Communication Framework

The Unified Communication Framework is a unified network protocol and FPGA firmware for high speed serial interfaces employed in Data Acquisition systems. It provides up to 64 different communication channels via a single serial link. One channel is reserved for timing and trigger information whereas the other channels can be used for slow control interfaces and data transmission. All channels except the timing are bidirectional and share network bandwidth according to assigned priority. The timing channel distributes messages with fixed and deterministic latency in one direction. In this regard the protocol implementation is asymmetric. The precision of the timing channel is given by the jitter of the recovered clock and is typically in the order of 10-20 ps RMS. The timing channel has highest priority and a slow control interface should use the second highest priority channel in order to avoid long delays due to high traffic on other channels. The framework supports point-to-point connections and star-like 1:n topologies for optical networks with a passive splitter. It always employs one of the connection parties as a master and the others as slaves. The starlike topology can be used for front-ends with low data rates or pure time distribution systems. In this case the master broadcasts information according to assigned priority whereas the slaves communicate in a time sharing manner to the master. In the OSI layer model the Unified Communication Framework can be classified as layers one to three which includes the physical, the data, and the network layer.