No matter what kind of cloud computing services operators plan to offer, they need to have an effective cloud database strategy in place or customers won’t have access to the necessary data in their cloud applications.
With that growing awareness, one of the most significant (and complex) cloud infrastructure issues facing cloud providers of many types is deciding how database support will be offered in the cloud, which is also leading to selling Database as a Service.
The wrong cloud database strategy can create application performance problems significant enough to discredit a cloud service, forcing the provider to incur additional costs to establish credibility with users. Ready or not, in 2011, database capabilities in the cloud are going to become a differentiator and a factor in sale for cloud providers.
The cloud database issue is complicated because it sits at the intersection of two cloud infrastructure models, two storage service models and two database management system (DBMS) models. Sorting out the details will require cloud services providers to consider their infrastructure, network performance and service goals.
The following services models can affect cloud database support:
- Single- and multi-site cloud infrastructure models. The two cloud infrastructure models differ in the way that resources are allocated to customers. In the single-site model, a customer’s applications run within a single data center in the cloud, even if multiple data centers are available. This means that the storage and/or DBMS resources used by a customer can be contained within a single storage area network (SAN), and that the customer’s application performance in the cloud can likely match that of a standard data center that uses virtualization. In the multi-site model, the customer’s applications can draw on resources from multiple data centers, which means that making the connection between the application and the database resources could involve WAN connectivity that limits performance. Whichever choice they make, service providers must be ready to address the issues that come with single- or multi-site cloud infrastructure.
- Storage and database service models. The storage service models available to a cloud planner are Storage as a Service or the more complex Database as a Service. With storage services, the customer will access virtual storage devices as though they were native disk arrays, which means that the applications will send storage protocols (such as Fiber Channel over Ethernet or IP SCSI) over any network connection. In the relatively new Database as a Service offerings, applications will access storage through a cloud DBMS that will accept high-level database commands and return the required results. This can create a less delay-sensitive connection, so it is better suited to cloud configurations where storage might be distributed over multiple sites.