Most companies that have implemented a heterogeneous storage network agree that putting together a new storage architecture is an extremely difficult process. Companies often cite problems with interoperability and technology manageability as reasons for slow adoption. Why do these problems exist, and why do they seem insurmountable?
Problems with interoperability and manageability are natural byproducts of the evolution of new technologies and standards. A natural lag-time occurs between the implementation of standards and products' increased interoperability, as vendors try to determine how to apply the standards to provide improved monitoring and management functionality.
This year, the Technical Council of the Storage Network Industry Association (SNIA) completed the SNIA Shared Storage Model, which describes a framework for various storage-system architectures and the services that use them. The model represents a major advancement for vendors and users in terms of definition and clarity in the nascent storage-networking industry and should accelerate the evolution and deployment of storage technology and standards compatibility.
The SNIA Shared Storage Model addresses all current and future storage system architectures, including Direct Attached Storage (DAS), Network Attached Storage (NAS), and Storage Area Networks (SANs). Similar to the Open System Interconnection (OSI) seven-layer networking model, the SNIA Shared Storage Model serves as a reference point rather than as a description of any particular technology or application: The model captures functional layers of a storage system (e.g., DAS, NAS, SANs) and describes interface points without referring to specific protocols or technologies.
Why is this type of reference so important? First, the SNIA Shared Storage Model gives storage hardware and software vendors a common vocabulary.
Although tacit agreement exists for most terms the industry uses to describe storage networks, without a model that clearly described interface points and architectures, some vendors defined common terms according to the variation their particular product provided. This self-generated vocabulary has caused confusion throughout the storage industry. For example, the lack of a clear definition for the term "virtualization" has confused both vendors and companies, making the term almost useless. Use of the SNIA Shared Storage Model's vocabulary can lead to common definitions for storage architecture elements.
Second, the SNIA Shared Storage Model provides a framework for discussion and design, nurturing familiarity with storage-system concepts. The model also includes a discussion of recognized necessary and value-added services.
Third, the SNIA Technical Council used a "layered" approach to describe the model, thereby helping vendors and customers clearly see where they need interoperability and where emerging standards are particularly important. The model uses simple terms to describe the location of interface points, thus letting vendors focus more on what differentiates their products and less on non-standards-based interoperability issues.
The SNIA Shared Storage Model is one of several solid initiatives that have come out of SNIA this year. As vendors and companies take advantage of the SNIA Shared Storage Model, it will prove to be a valuable tool with the potential to accelerate the development of interoperable storage networking products.
