Therefore, SDI integrates its concepts and related components hierarchically (vertical integration) and expands it in societies (horizontal expansion) [10]. The vertical integration developed through datasets integration, duplication reduction and stakeholder participation concept. Also, the horizontal expansion, which mainly utilizes ICT, illustrates capacity building, awareness and knowledge infrastructure development and applied in base of the pyramid defined in Figure 3, which results in this base expansion (Figure 4).

Figure 4: ICT diffusion effect on organizational pyramid [19]
ICT Evolution
Considering the above-mentioned matters, NSDI leads all of its components towards the main aim of achieving sustainable development. Here, existing ICT infrastructure could act as NSDI and sustainable development enabler. However, weakness of ICT strategy and policy in developing countries and their pervasive priorities have confronted them with serious problems [1,2,7]. In this situation NSDI could create its required foundation dealing with ICT introducing various operational capabilities of ICT as one of SDI components. Then, ICT will simultaneously be developed in NSDI evolution trend. The main evolution here emerged from ICT strategy development through NSDI activities [27].

SDI development process as an innovation is illustrated in three phases known as initiation, implementation and establishment [27], reveals ICT strategy as an enabler [1] which is based on development subject. Also, this strategy will be implemented and established through these three phases (esp. for GI) development and results strategies which introduces ICT as a sector as follow [1,12]:

• ICT diffusion strategy, which supports public benefits and ICT publication adopting with local conditions (National Capacity/Domestic Market).
• ICT market stimulation strategy, which empowered economical aspect, competition environment, ICT benefit making and its self-dependency (Export Market) considering ICT as a tool.

Finally, an integrated and powerful strategy will develop from these sector and background strategies for sustainable development, which enables ICT and SDI further evolution.

Conclusion
Sooner or later, all societies have to move towards ICT utilization and any delay will threat their further development more. Understanding this situation in developing societies, which needs ICT establishment urgently for their sustainable development. Various impediments could be mentioned in social, cultural, political and economical aspects result in a complex condition for sustainable development. Then, other activities, could handle this complexity through ICT utilization, are investigated. GI and related activities have represented proper and required capabilities and could provide the aims of sustainable development. Finally, experiences introduce SDI as a comprehensive and proper solution for simultaneous evolution of ICT and sustainable development especially in developing societies.

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