The Department of Spatial Information (DSI) is a State Government department. The major function of DSI is to provide accurate and timely spatial information to other Government departments, but also to make some of this spatial information available to the public. In order to provide both the government and public services, DSI has developed a number of web services that deliver this information through a number of internally developed services and applications. This suite of web services and applications is referred to as the DSI Online Spatial Delivery System (OSDS).

The OSDS is considered essential by DSI and their users, so these services must be:

• Readily available and accessible at all times,
• Capable of handling heavy loads in times of peak      demand,
• Capable of serving downloads to users as required,
• Secure from attacks,
• Capable of providing detailed reports on usage.

DSI have a number of new projects being developed that are expected to increase the demand for its spatial data dramatically. The Executive Management of DSI have looked at a number of proposals to support these new programs. The two alternatives they are investigating are:

1. Increasing the internal DSI Data Centre capacity to      host and support the new projects in the OSDS. This would probably need a      50% increase in web infrastructure and support services within the      Department. This would necessitate an increase in data centre      infrastructure, server numbers as well as a major increase in the      bandwidth available to DSI.
2. Migrating the OSDS to a Cloud provider. This would      allow DSI to continue to develop and refine the data in its internal      Maintenance systems and then move a copy of the completed data to the      cloud-based Delivery system for publication.

DSI Management would like to adopt Proposal 2, in order to meet their budget restrictions,  but have asked you to prepare a report for the DSI Board that looks at the following aspects of the proposal:

1. The possible delivery and deployment models that DSI      should adopt for a cloud-based OSDS. This should include:
   1. The advantages and disadvantages of using either an       IaaS or PaaS approach for the OSDS and
   2. The possible architecture(s) that could be used to       deploy the OSDS
2. Should the Board consider the use of an Cloud Edge      solution for the OSDS? What advantages and disadvantages would the Edge      give to the OSDS?
3. The OSDS software architecture uses a monolithic      approach to design, while a move to use the Edge will require many      applications and web services to be redesigned as microservices.
   1. Explain the differences between monolithic and       microservice architectures to the DSI Board using an example
   2. Describe the advantages and disadvantages of these two       styles of software architecture
4. Your recommended approach for delivery and deployment      of the OSDS, including the reasoning for your recommendation

Your report should not exceed 10 pages, excluding references.