The Technological Framework that proposed within the National SDI model and through which users will access the located datasets, consists of three components: i) Policies, ii) Standards and iii) Access Network.

As countries worldwide develop National SDIs, the need for standards is becoming a basic requirement. Standards are useful for producing, sharing, accessing and using data. They, also, ensure compatibility between data from different resources (e.g. built and natural datasets).

Since Greek National SDI will be node within the European SDI, it would be benefi cial to comply with European standards (ISO/TC211, CEN/TC287 - 278, and OGC). Therefore it is not required for Greece to create new standards. If European standards are followed, there will not be issues of interoperability within the Regional SDI.

Policies, within the environment of SDI should be able to address reliability, testability, verifi ability, accessibility, usability, interoperability and maintenance of spatial data (Wallace, 2005). So far, policy making within Greece is incomplete (Orshoven and Beusen, 2004). However, the need for detailed policy on accessing data and particularly sensitive data (e.g. military buildings, culturally protected areas, personal data) is necessary in building of National SDI. A Policy WG that has been proposed under the SDI Coordinating Council will set policy that will cover public, private sector and academia and support privacy, security, confi dentiality and intellectual property rights within the jurisdiction. Each organization should be responsible to respect and enforce that policy. Moreover, the development of national guideline policy documents, which will be supported by legislation and be available both to stakeholders and users of spatial data, will signifi cantly foster the success of SDI.

Metadata provides information about stakeholder of the data, so users know where they should acquire the data. It presents information about the date of data creation, any potential update of data, its accuracy, geographic extent and coordination system and other technical description. With this information users can assess whether or not the data is suitable for their applications.

For the Greek SDI, based on the proposed metadata by Information Society (section “Current Initiatives in Spatial Data Infrastructures”), users are able to get information about the technical characteristics of the data and their stakeholders and therefore to judge whether the data is appropriate for their needs. Thus, the list is complete and it does not require any change.

The number of the core data layers within the SDI varies among ifferent National SDIs, and depends on the geography of the country, the strategies of SDI Coordinating Council and the Regional SDI that the National belongs to. Regarding the Greek National SDI, the number of proposed core data by Information Society, is fifteen (section “Current Initiatives in Spatial Data Infrastructures”). According to ETeMII (2001) (European Territorial Management Information Infrastructure), the proposed core data for both Regional and National SDIs are the following six: i) Geodetic reference system, ii) Ortho-imagery, iii) Topographic mapping, iv) Units of property rights, v) Addresses, vi) Units of administration

Although Information Society’s proposal includes all the layers of the ETeMII’s list, none of them contain offshore data as a core layer. Having in mind that Greece has a very long coastline, marine cadastre should be considered as one of the core layers in National SDI. Therefore, the conceptual National SDI model, proposed in this paper, contains marine data as core dataset (Figure 5). In this approach, sustainable development will be promoted in advance.

Another important SDI component is the people. This includes private companies, public organizations, academia, and individuals, who provide data or need it to develop applications or produce other data. Their relationship is vital, since all these groups are required in order to have, integrate and utilize data effectively. Moreover, people are the driving force of SDI development, because of the very strong relationship they have with all the other components of SDI platform. For instance, people establish the access network and set policies and standards according to which they access data. Thus, SDI initiative starts and ends with people and their desires drive the evolution of SDI concept. Therefore, all residents of Greece should be allowed to access the data.

The SDI roadmap is important for the implementation of National SDI, because without following any action schedule the project will not be successful. The development of such a plan depends upon socioeconomic, technological and political conditions of the country. Since SDI development is by nature a long-term project and a country’s status is always evolving, SDI implementation plan should encompass dynamic approach of the required actions. Considering the current status of Greece, a roadmap for the country’s National SDI is proposed (Figure 6). Within the SDI development, if it is feasible, some activities can be implemented in parallel. A specifi c duration is difficult to be given, because of the evolving nature of the SDI platform.

A major priority for the Greek jurisdiction is the formation of the SDI Coordinating Council, since it will have leading role in National SDI. In this stage, the appropriate WGs will be created and memberships and responsibilities will be delegated to proper sectors. Next step is to define the SDI vision and mission, so as the country to have a clear target to achieve. Since one of the main tasks of the Council is to determine strategies, the SDI strategies action follows. By clarifying the strategies, the country saves time and money from unnecessary activities.

While the selection of the Council members takes place, the government is able to develop and propose organizational structures able to support the establishment and maintenance of SDI. Within this task the capacity building will be reformed, so as the involved sectors to get improved and
qualifi ed, to support the SDI project.

The SDI conceptual design can be developed after the formation of SDI Coordinating Council, because at that time the responsibilities would have been allocated and each member will have clearly defined task. After the half part of this stage, the country has clear idea of what they will implement and therefore, the development of the SDI implementation plan can begin.

Then, the actual implementation phase follows. It consists of pilot projects to be completed in the early stage of the phase. These foster the smooth execution of the project, acting as a test for proposed methods and plans. During the pilot projects implementation, they are assessed and the jurisdictional major projects will start. These can be either shortterm or long-term projects. Regarding the deliverables during the SDI implementation, these will be annual reports relevant to the activities that take place in each phase.

In addition, the government has to develop a benchmarking strategy to monitor SDI progress with corresponding activities in Europe. Indicators, such as the level of awareness, capacity in the community and system availability can be used in this process. Also, the maintenance of the overall platform is very important, in order to have a functioning SDI. A clear maintenance and support strategy is needed. SDI maintenance is difficult and challenging and requires effort and finance. The country has to maintain and upgrade the institutional structure as well as the SDI components.

This paper evaluated the current situation in spatial activity in Greece, discussed the major issues for the development of a Greek National SDI and proposed a National SDI conceptual model and its components. Finally, it proposed a roadmap for a complete and consistent implementation of the National SDI platform. The roadmap covers the initial steps of the SDI implementation in Greece and can act as a guide for those with key roles in promoting, adopting and developing SDI.

Concluding, although this paper highlights major issues for Greek National SDI, lessons can be learnt from it and applied in other jurisdictions. Different countries with diverge priorities and cultures need different SDI development models. However, by investigating various countries’ SDI activities, strengths and weakness become apparent, therefore allowing countries to learn from one another.

The authors would like to acknowledge the financial support from the State Scholarships Foundation of the Greek Government and the Centre for Spatial Data Infrastructures and Land Administration of the University of Melbourne, Australia. However, the views and opinions expressed in this paper are those of the authors and do not necessarily refl ect the position of the above mentioned organizations

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