This month’s correct answers came from three times winner Lionel Griache at ProactiveRA, and Srinivas Chikkala from India.
To solve LTT-03 some basic CDR reconciliation matching between MSC1 & MCS2, to the interconnect I/C Gateway was required. The results would show there are some CDRs present at the interconnect I/C Gateway, but are not present on MSC1 or MSC2. The missing CDRs correspond to off-net calls with a short duration of under 5 seconds.
Browsing through the CDR data of both MSC1 & MSC2 shows there are no calls under 5 seconds of duration, which indicates the problem could also include on-net calls as well. Although it is not possible to determine if the calls originated from either MSC1 or MSC2, the lack of calls under 5 seconds in them both points to the problem being in the two switches. Therefore, the most likely cause of the revenue leakage will have to be answer C – MSC1 & MSC2.
The next LTT will be published on Monday 15th April.