What are some of the possible ways that data can flow through a real-time cloud system? In his book, Cloud Economics, Joe Weinman suggests a triangular relationship between the three key players in the cloud game: user, enterprise, and cloud. He classifies the “user” as the consumer of the data, as well as the producer, or both. He then goes on to show how in a hybrid cloud architecture, there are six possible relationships between the key players.
This is a helpful way to look at things, but I would take it one step further for a real-time hybrid cloud. Since in a real-time system the data producer is usually a device, instrument, or machine, and the data consumer is often a person, it might be helpful to look at the architecture as a diamond, instead of a triangle. To Weinman’s three players, we could add a fourth: data source.
The resulting four-cornered diamond shape is helpful for illustrating the possible data paths through the cloud system. For example, the pre-cloud data path is from the data source through the enterprise to the user. We might then expect that implementing a cloud solution would switch the path to go from the data source through the cloud to the user.
Those would seem to be the two options, in an either/or world. But when we consider the possibilities of a hybrid cloud, more paths become possible, and in many cases more useful. For example, most industrial users keep tight control on their systems, and would not think of exposing their data sources directly to the cloud. However, if the system architecture incorporates the core principles of real-time cloud design, then one path of selected data for qualified users could be from the data source to the enterprise, and from there to the cloud and the user.
In that same scenario, it could be that some users get data directly from the enterprise itself part of the time, and from the cloud at other times. For example, an operator at a plant may view a SCADA system on a control panel, but when walking around the plant, or when on call during the weekend, could receive notifications and a critical subset of the data on a table or smart phone, via the cloud. So the data from the source would go to the enterprise, and then directly to the user, or via the cloud to the user, depending on the needs.
In some circumstances, the enterprise may be a secondary recipient of the data. For example, if the data source is another company that is supplying its data over the cloud. Or in the case where the system design favors putting data from sensors or other field devices on the cloud first. In these cases, both the users and the enterprise would interact with the data via the cloud.
These are a few of the possible data paths for a real-time hybrid cloud system. At any given time an application may use these or other paths, depending on the needs of the users and the limitations and requirements of the system. This inherent flexibility of the architecture makes a hybrid approach an attactive option for many real-time cloud applications.