Enterprise Application Integration
You need to consider how your system integrates with other systems in your organization. Clouds are good but one-off systems that use cloud but do not integrate with existing systems will diminish the payoffs of using a cloud.
You need to consider how your system and its data get integrated with existing data. This may need to be done both ways. Without access to existing data or data created and maintained by your cloud based system, you will again limit the potential of your system under design.
You may also need to integrate your application with your enterprise’s existing authentication and authorization solution.
Even if integration is not an immediate concern, an architectural choice can make it impossible to integrate even in future. You will need to worry about different networks and firewalls and if the protocols you will use to integrate these systems will work across these networks and firewalls.
Development Considerations
Once you start building the system, you will need to take into account how many engineers and support people are comfortable with the technologies you are using (in this case – something cloud based). You may need to take training and documentation time into account in your plans.
If you need to move large amounts of data between your internal computers and the cloud, you will need to either have sufficiently fast network connections or take the associated delays into account. This delay could play a major role in how you trouble-shoot issues, provide other kinds of support, take backup or just make the data collected by your application available to the users within your internal network.
Offshore development is a reality and if your application is either developed and/or maintained by a team working offshore, network speeds, latency and round trip times will all come to play a major role. This means your choice of development and support tools and environments should work well over a bad network. VNC and Xserver-clients do not behave well, text terminals work better, light-weight HTML based clients work best. You also need to worry about moving large amounts of data in and out of the cloud from your development and support centers.
If you have specific regulatory compliance requirements, you need to be sure that the platform complies with the standard. For example, Amazon EC2 instances are not PCI (payment card industry) compliant so you should not plan on storing credit card information on Amazon EC2 instances. There could be regulations regarding sending customer data out of country and when you store data in a cloud, you (or even the provider) may have no control on where (which node) that data could be at any given time.
