If I subscribe to a Platform as a Service provider, am I locked into Software as a Service and Infrastructure as a Service from the same cloud vendor? What technologies and service providers allow me to subscribe to PaaS, SaaS and IaaS from different cloud service providers?
If you subscribe to a PaaS vendor, you will be limited to using IaaS and SaaS products that are compatible with the Platform as a Service you choose, but not necessarily from the same provider. The SaaS apps must interoperate with the PaaS and be portable -- or movable -- across multiple IaaS cloud providers.
Interoperability between the PaaS and SaaS products is typically required for the two to effectively exchange data. This exchange requires a secure, reliable communication path, so data must be in a format that's compatible. This effort is much easier if the two cloud service providers share common application program interfaces (APIs).
The portability of your PaaS product across multiple IaaS cloud providers is a more common concern, especially in terms of vendor lock-in. The current PaaS market presents a challenge because it is still quite young and highly fragmented, with each cloud provider promoting its own incompatible standards.
Several PaaS development groups are working to establish a set of standards and common APIs to act as the middleware between IaaS and SaaS installments. These initiatives include:
- The Cloud Application Management for Platform (CAMP), which contains 10 PaaS cloud vendors that specify a common development API;
- The open source VMware-sponsored Cloud Foundry PaaS project, which supports its Cloud Foundry Core framework as a standard; and
- The OpenStack Foundation, whose members include Rackspace, HP and IBM, among others, and which has created the Topology and Orchestration Specification for Cloud Applications (TOSCA) for PaaS application portability within the OpenStack community.
You'll want to review each of these approaches if you are selecting an IaaS and PaaS cloud service provider for the first time. If you're already using an IaaS provider, however, you may want to look at what is available from PaaS Virtual Appliance vendors. These companies create turnkey PaaS, such as Application and Database Servers that are already preconfigured to run on multiple clouds. Companies in this space include Engine Yard, Jump Box and Open Logic.
About the author
With a background in managing one of the largest global financial networks, Mark Szynaka brings his network monitoring, security and ITIL best practices to the cloud. He helps enterprise IT investigate and implement cloud computing architectures -- public, private and hybrid -- using Amazon Web Services, Terremark/Verizon and Rackspace technologies.