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AM Initialisation

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SS Problem

Clock/NSC

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Oneway speech

Call Processing

In MBM configuration the switching is TST switching; thus the role of CM in call processing is very crucial. As the CM architecture is BUS architecture thus the call processing is BUS wise, i.e. there is a alternate call flow from alternate BUS. Thus there is role of SSM/PSM card in the BUS and SSS/PSS card of SS plane corresponding to BUS is quite crucial.

If we make one BUS 'OOS-OPR' then all call goes through same BUS.But now there is an active role of SS in the call processing, as it controls the BUS along with the CMS. Especially in the speech path there is an active role of SS plane. As per the configuration there are four PSS/SSS card as SWC which came in picture for four BMs i.e. SWC1-0 & SWC9-0 of SS-0 for BM1to BM4 where SWC1-0 for BUS0 (IFC1 & IFC2) and SWC9-0 for BUS1(IFC17 & IFC18) similarly SWC1-1 & SWC9-1 of SS-1 for BM1 to BM4 where SWC1-1 for BUS-0 (IFC1 & IFC2) and SWC9-1 for BUS1(IFC17 & IFC18).
Case1: We found that all the calls are successful but some calls are noisy and some are perfectly OK without any noise. This is the case when there is a problem in one BUS and another BUS is working perfectly. As for the call processing the call lands on alternate BUS thus when call lands on OK BUS the call is OK but when it lands on noisy BUS the call became noisy
Case 2: We found that some calls are perfectly OK and some are one-way (i.e. no RBT but ring at the terminating subs.)