Specifications

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ATM-A OC3 544 1058
ATM- OC3A SMF PIC 464 769
ATM- OC3A MMF PIC 597 985
ATM-A OC12 535 1029
OC12-1B SMF ATM PIC 815 1331
OC12-1 MMF ATM PIC 1055 1709
DS3-2-A PIC 559 860
DS3-2-B PIC 866 1201
Gigabit Ethernet Module LX 583 1112
Gigabit Ethernet Module SX 656 1198
Predicted System MTBF
Component
MTBF in (khrs) at
40°° C
MTBF in (khrs) at
25°° C
M20 chassis only 108 198
M20 chassis with SSB 77 136
M40 chassis only 108 198
M40 chassis with SCB 77 136
OC3 POS Interface 46 80
OC12 POS Interface 54 93
ATM OC3 2 Port Interface 39 70
ATM OC12 Interface 40 72
OC48 Interface 60 104
DS3 Module 54 93
Gigabit Ethernet Interface 59 104
The reliability analysis used Method 1, Case 3: General Case using Black Box
option with unit/system burn-in > 1 hour but no device burn-in. Please refer to
Bellcore Reliability Prediction Procedure (RPP) for Electronic Equipment TR-
NWT-000332 (a module of RQGR, FR-796) for calculating basic core reliability
mathematical models and Reliability Engineering by Bryan Dodson for calculating
serial and redundancy models.
4.4.2 Mean-Time Between Failure Data for the M160
The purpose of this analysis is to predict the system reliability of different
data paths for the M160 system. Reliability analysis used Method 1, Case 3:
General Case using Black Box option with unit/system burn-in > 1 hour but
no device burn-in. Please refer to Bellcore Reliability Prediction Procedure
for Electronic Equipment TR-NWT-000332 (a module of RQGR, FR-796) for
calculating basic core reliability mathematical models and Reliability
Engineering by Bryan Dodson for calculating serial and redundancy models.
Please note, software and mechanical reliability are not considered.
M160 SYSTEM RELIABILITY ANALYSIS PER ELEMENT
MTBF (khrs) ** Availability (At 40C)
40C 25C MTTR = 24hrs MTTR = 12hrs
* Power Supplies (1:1) 300 675 0.9999200 0.9999600
* Fan Trays Top & Lower (1:1) 1500 2625 0.9999840 0.9999920
* Fan Trays Rear (1:1) 3300 5775 0.9999927 0.9999964
Backplane 240 435 0.9999000 0.9999500
* SFM (1:4) 246 435 0.9999024 0.9999512
* MCS (1:1) 326 528 0.9999264 0.9999632
PCG 445 709 0.9999461 0.9999730
* Routing Engine (1:1) 450 750 0.9999467 0.9999733
FPC-1 (CPU, 4SRAM, 8DRAM) 80 143 0.9997001 0.9998500
FPC-2 (CPU, 4SRAM, 8DRAM) 81 144 0.9997038 0.9998519
OC3 POS SMF OC3A PIC 464 769 0.9999483 0.9999741