Software-Defined Storage: Principles, Practices, and Ecosystem – An Overview and Book Recommendation

The article begins by noting that the accompanying image advertises a book on software-defined storage (SDS) and invites readers to explore the technology rather than merely view a commercial promotion.

It outlines the origin of SDS, explaining that the term emphasizes resource transparency and layered abstraction, similar to the broader “software‑defined everything” trend highlighted by Gartner in 2013 and supported by open‑source projects such as OpenStack, OpenFlow, and OpenRack.

In August 2012, VMware introduced the Software‑Defined Data Center (SDDC) concept, separating management, infrastructure, control, and application layers; SDS was presented as the storage component of this architecture.

The technical background section argues that SDS is driven by innovation from startups and a few forward‑looking vendors, especially in Israel, and is enabled by trends such as the X86‑based storage hardware, multi‑core CPUs, high‑speed networking (PCIe, InfiniBand, NVMe, RDMA, 10/40 GbE), and the increasing capacity of disks and flash.

Business‑level motivations are described, highlighting the inefficiencies of traditional “siloed” IT infrastructure and the demand for transparent, pooled, and hierarchical storage resources that can be provisioned on‑demand.

The article then presents several definitions of SDS from organizations like IDC, ONF, and SNIA, emphasizing automation, standard APIs, virtual data paths, scalability, and transparency.

Three primary SDS categories are identified: storage‑function virtualization (decoupling software from hardware), storage‑compute convergence (e.g., Nutanix), and separation of data and control planes (e.g., EMC ViPR, Huawei DJ), all leveraging commodity hardware.

Future directions are discussed, including controller‑data‑plane decoupling with RESTful interfaces, hyper‑converged flash‑based NAS solutions (e.g., Elastifile), integrated block‑file‑object platforms (e.g., Formation Data System), and cold‑storage services that replace tape with cheaper, reliable archival options.

Finally, the recommended book is presented as a comprehensive resource covering cloud computing, big data, mobile and social networking contexts, and detailing products from more than twenty vendors, offering readers a systematic view of SDS definitions, evolution, classifications, and trends.