1. A large-scale Atlas LVL2 test bed based on a programmable hardware ROB emulator J. Lokier, M. Dobson, M. LeVine

2. M. LeVine 9 June, 2000Reference Software Workshop

3. M. LeVine 9 June, 2000Reference Software Workshop

4. M. LeVine 9 June, 2000Reference Software Workshop Fast Ethernet tester: purpose (J. Lokier, B. Martin) zGenerate programmable network traffic to characterize network switches zDifferent sorts, mixtures of traffic: IP, Ethernet yIncluding QOS zInstrument packets with timestamps zRecord (histogram) results

5. M. LeVine 9 June, 2000Reference Software Workshop FE tester: capabilities & status z32 ports full-duplex fast Ethernet zParallel port connection to host zMAC function: FPGA programmed in Handel C zIncoming packets time stamped, CRC checked zRequests queued, descriptors generated zQueue dwell times histogrammed zOutput packets generated, time stamped zAll of this at full line speed (100 Mbit+100 Mbit)! zStatus: board is being populated in 1 week

6. M. LeVine 9 June, 2000Reference Software Workshop FE tester as ROB emulator zAccepts MESH ROB_DATA_REQUESTs zGenerates MESH ROB_DATA_REPLYs yProgrammable latency in ROB yResponse size depends on ROI size and detector type yResponse contents not meaningful zAdd instrumentation fields to Reference Software messages… zMeasure latencies and queue depths

7. M. LeVine 9 June, 2000Reference Software Workshop Large scale test bed using ROB emulator zUse 8 of these boards [15k CHF each] to provide 256 emulated ROB ports zAdd: y128 PCs (from IT) - supervisors + farm nodes y128 GBE NICs ySwitch fabric zWe have a ~25% scale test bed of Atlas LVL2

8. M. LeVine 9 June, 2000Reference Software Workshop Test bed capabilities zSupervisor (PC) generates ROI patterns using simulated events zMeasure request-response latency zMeasure queue dwell times in ROB yTimestamp on request arrival and response generation zMeasure queue occupancy distribution yNot possible with software emulation zMeasure frequency of broken messages under realistic conditions in real switches

9. M. LeVine 9 June, 2000Reference Software Workshop Summary zLarge scale test bed minimizes uncertainty associated with behavior extrapolated from a few nodes zHardware ROB emulation provides opportunity to see network behavior under realistic conditions zParticipation is open ….