1. WPFL General Meeting, 06-07-2010, Nikhef A. Belias1 Shore DAQ system - report on studies A.Belias NOA-NESTOR

2. WPFL General Meeting, 06-07-2010, Nikhef A. Belias2 Shore DAQ Tasks Receive all data from telescope (PMTs / Controls/ Earth & Sea-science)  ALL DATA TO SHORE Process data to extract events & calibration constants  ON-LINE DATA FILTER OF WHOLE TELESCOPE Archive events and operational conditions  EVENT, CALIBRATION, RAW DATA, DETECTOR STATUS Control and monitoring readout components  MISSION CRITICAL AND SUB-CRITICAL UNITS Update local Data Bases & export to remote sites GRID  VALIDITY CONTEXTS AND CACHE COHERENCE

3. WPFL General Meeting, 06-07-2010, Nikhef A. Belias3 Data aggregation scheme ALL data are sent to shore Expected rate of 100-300Gb/s cannot be just stored Concentrate all data in temporary buffers Aggregate a time-slice of data of whole telescope Process on-line in trigger farm sequences of time- slices Time-position-amplitude correlations of PMT hits in real-time for the whole telescope Archive event data, calibration data, fraction of raw data

4. WPFL General Meeting, 06-07-2010, Nikhef A. Belias4 GRID DAQ architecture Option A Optical Demux MEOC O/E BIG FPGA Many Transceivers Multiple 1Gbit Ethernet Gbit Ethernet Switch fabric 1 Gbit Ethernet Data Base 1 Gbit Ethernet Gbit Ethernet Switch fabric 1 Gbit Ethernet Data Processing Farm Node 1 Node 2 Node 3 Node N Archive Run Control & Monitor Server Run Control & Monitor Server BUFFER SYSTEM

5. WPFL General Meeting, 06-07-2010, Nikhef A. Belias5 data OM n # 1 22-03-20105 e.g. dual port memo DP mem # 1 Mem. address counter/generator WAP (Write Address Pointer) RAP (Read Address pointer) WAP 1 WAP 2 WAP 3 WAP n Heartbeat 311 MHz Value’s for address offsets (signal propagation time measurements for each point to point connection) data OM 1 data OM 2 data OM 3 Event data from e.g. a DU Prop. Value 1Prop. Value 2Prop. Value 3Prop. Value n Mem control logic system RAP Equal for all memories Data Aggregation (Example using the NIK) Real time received data available for time sliced readout Time phase (offset) Wiki text: Round-robin (RR) is one of the simplest scheduling algorithms for processes in an operating system, which assigns time slices to each process in equal portions and in circular order, handling all processes without priority. Round-robin scheduling is both simple and easy to implement, and starvation-free. Round-robin scheduling can also be applied to other scheduling problems, such as data packet scheduling in computer networks. Dual port memory for Round Robin scheduling Determinated fixed relative time offsets Data word OM 1 Shore # 2# 3# n rel. time offset

6. WPFL General Meeting, 06-07-2010, Nikhef A. Belias6 Simulation studies Study attainable performance of readout. Investigate consequences of sudden PMT rate bursts, dedicated calibration runs, overlapping time-slices and triggers. Queue modeling to determine latency issues, buffer requirements, processing power. Started with simulations of “vertical slice”. Simulations can help to defer buying h/w to get best performance at low costs.

7. WPFL General Meeting, 06-07-2010, Nikhef A. Belias7 GRID DAQ architecture Option B Optical Demux MEOC O/E BIG FPGA Many Transceivers x 5 18 lines 1Gbit Ethernet Gbit Ethernet Switch fabric 1 Gbit Ethernet Data Base 1 Gbit Ethernet Data Processing Farm Node 1 Node 2 Node 3 Node N Archive Run Control & Monitor Server Run Control & Monitor Server Buffer

8. WPFL General Meeting, 06-07-2010, Nikhef A. Belias8 Summary & Status The DAQ on-shore must have the flexibility to adapt and the modularity to scale. The use of FPGA systems allows for flexibility in hardware. The use of mass market, industrial, systems allows long term (10+ years) maintainability at low costs. Work on data aggregation using FPGA and the PON has started Simulations studies of system performance have started.