11.6 Multivendor Storage Virtualization

Although the SNIA is attempting to define the basic characteristics of storage virtualization to determine whether standardization can be applied, to date little progress has been made toward an open systems approach to storage virtualization. This is not because of lack of interest or support by vendors and customers. Instead, the causes are the complex facets of the virtualization gem and the difficulty of retrofitting a standards-compliant framework onto storage arrays whose added value is already based on deeply proprietary technologies.

Because storage-based virtualization is inherently proprietary, heterogeneous SANs must rely on either host-based or interconnection-based solutions. Given the administrative overhead of host-based virtualization, interconnection-based solutions are by default more suitable for larger multivendor storage networks. With the caveat of potential performance bottlenecks, interconnection-based solutions can at least accommodate heterogeneous server platforms upstream and mixed environments of RAIDs and JBODs downstream with less administrative overhead. Reduction of administrative overhead and its associated costs is, after all, one of the main drivers of virtualized storage solutions.