as you says the MSISDN is composed by:
CC+NDC+SN
Its total length is max 15 digits.
CC (country code) can be from 1 to 3 digits.
NDC(national destination code) + SN (subscriber number) have a max length of 15 digits minus length of CC.
I work in a telecom company..
In one of the tables for our product, I got some imsi values as 0 for some records and some msisdn values as 0 for some other records.. So is there any way out that I can come to know why its showing 0 for imsi and msisdn???