363-206-305
Technical Specifications
Issue 3 June 2000
10-61
DDM-2000 FiberReach System Reliability 
Predictions 
10
Table 10-26 and Table 10-27 show the system reliability predictions for the DDM-
2000 FiberReach Multiplexer.
Table 10-26. DDM-2000 FiberReach System Reliability Prediction.
*
Field replacement rate estimates, based on field CP returns and repairs, are used for the component whose failure  
is silent service affecting and/or not service affecting.
Notes:
 
 Environment 
Telcordia Technologies 
Criteria (Note 3)    Prediction (Note 4) 
Application  (Note 2)  Requirement  Objective  Outage (min/yr)  MTBF (Yrs) 
Point-to-Point
DS1 to OC-1  CO  1.75  0.25  0.1657  724 
DS1 to OC-1(*)  CO  1.75  0.25  0.0463  2590
DS1 to OC-1  RT  5.25  0.75  0.4971  482 
DS1 to OC-1(*)  RT  5.25  0.75  0.1391 1723
DS1 to OC-3  CO  1.75  0.25  0.1657  724
DS1 to OC-3 (*)  CO  1.75  0.25  0.0463 2588
DS1 to OC-3  RT  5.25  0.75  0.4972  482 
DS1 to OC-3 (*)  RT 5.25 0.75 0.1394 1719
DS3 to OC-3  CO 1.75 0.25 0.1983 605
DS3 to OC-3 (*)  CO 1.75 0.25 0.0219 5479
DS3 to OC-3  RT  5.25  0.75  0.5953  403
DS3 to OC-3 (*)  RT  5.25  0.75  0.0661  3617
Ring Pass-
Through
OC-3c to OC-3c CO none none 0.00006 1554735
OC-3c to OC-3c RT none none 0.00052 345505
OS Interface
TBOS 
(Note 5
)  CO  —  14.00 4.74  25 
1. 
Hardware failure rates are calculated per the RPP method, TR-NWT-000332, Issue 4, 
Reliability 
Prediction Procedure
. 
2. 
The environmental factor for the CO = 1.0 and for the RT = 1.5, per TR-NWT-000332, Issue 4, 
Reliability Prediction Procedure
. 
   
  (Notes continued on next page)