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Business case fraMewOrk
In all countries, PSTN migration is expected to have a sustainable
impact on long-term platform cost development and to require signifi-
cant investments for migration of the full customer base from the old
PSTN legacy network to the IP world. e benefit of performing the
migration needs to be calculated and monitored through a business case
making a financial impact, as well as ambition transparent, to all involved
functions in the project, local decision bodies, and other stakeholders.
e business case could simply be constructed by comparing migra-
tion costs to cost savings due to the shutdown of PSTN platforms.
Experience shows that migration from PSTN to IP technology costs
around 30€ ($38) to 60€ ($75) per subscr ...