· C.3 – Slim centralization with managed service: The GNMC has mainly a support role of local operations. This can be used to cover monitoring activities such as night shifts, weekend or public holidays.

· C.4 – Centralized monitoring with managed service: A GNMC is built and NOC monitoring responsibilities are shifted. The other O&M functions are outsourced to an external supplier.

· C.5 – Centralized reporting: O&M responsibilities remain unchanged. The GNMC is responsible for consolidated performance management, reporting and communication with MNC and management.

· R.1 – Slim regionalization with tailoring: The regional network management centers (RNMC) mainly have a support role of local operations. This can be used to cover monitoring activities such as night shifts, weekend or public holidays.

· R.2 – Regionalized monitoring: NOC monitoring responsibilities are shifted to RNMC. Back-office functions remain local responsibility. Field maintenance and E&M maintenance are outsourced to an external supplier.

· R.3 – Regionalized core & VAS: Regional NOC are built and all O&M functions related to core & VAS are shifted. The responsibilities for the other technical domains remain local.

· R.4 – Regionalized back-office: 2nd level activities and coordination of 3rd level support are done by RNMC.  Monitoring is performed locally and field maintenance is outsourced to an external supplier.

· R.5 – Aggressive regionalization with managed service: RNMC are built and NOC responsibilities are shifted. At the same time field and E&M maintenance are outsourced to an external supplier.

Our simulation results regarding cost reduction forecast vs. the qualitative/strategic assessment of quality and control (which was scored using a separate model) are shown in fig. 4

Scenario R.5 “Aggressive regionalization with managed service” appears to be the most attractive scenario: It combines high economic impact with desirable strategic aspects (keeping control and in-house O&M know-how to ensure high quality-of-service). It could be implemented directly, or – as we would recommend – migrating through other scenarios as intermediate steps to ease transition and reduce risks: R.1 “Slim regionalization with tailoring”, or R.4 “Regionalized back-office”.