EGI is composed of a small central coordinating body (called the EGI.eu) and National Grid Initiatives (NGIs) performing the following tasks:

1. Authentication of individual users as the people they claim to be.

2. Allocation of project or discipline collaboration members to VOs where resources are shared.

3. Allocation of computing resources to those VOs which VO members will be authorized to use.

4. Authorization of VOs to run computing jobs, store and retrieve data on individual computing resources (machines, data centres, facilities, etc.).

5. Distribution and scheduling of computing jobs, workflows, data retrieval and access requests to authorized computing resources.

6. Monitoring of the jobs submitted, processed, and the data stored by individuals.

7. Accounting of users and VO in their allocations and usage of computing resources.

8. Reporting to each NGI of their allocation of resources to VOs, and the use of those resources by individual users, in order to enable the NGI and the national funding bodies to account for the use of funds in terms of the research results produced by VOs.

9. Coordinated management of software updates and hardware upgrades while maintaining a continuous service.

The NGI in each member state needs to support these functions so that it can interact with EGI. The activities of the NGIs are not limited to the tasks that each NGI performs at national level to maintain its infrastructure, but extend to international tasks that allow the sharing of IT resources in a robust and transparent way and the support of the international application communities. The characteristics of the NGIs can be identified as follows: Each NGI should:

• be the only recognized national body in a country with a single point-of-contact representing all institutions and research communities related to a national grid infrastructure;
• have the capacity to sign the statutes of EGI.org – either directly or through a legal entity representing it;
• have a sustainable structure, or be represented by a sustainable legal structure in order to commit to EGI.org in the long term;
• mobilise national funding and resources and be able to commit to EGI.org financially, i.e. to pay EGI.org membership fees and – if there is a demand for such services in the NGI – request and pay for EGI.org services;
• ensure the operation of a national e-Infrastructure to an agreed level of service and its integration into EGI;
• support user communities providing general services to the applications and fostering the grid usage for new communities;
• adhere to EGI policies and quality criteria.