Software-Defined Deluge: Promises, Pitfalls And Players

Software-Defined Whatever?

Ever since the term "software-defined networking," or SDN, moved from geek status to become a widely recognized trend via VMware's monster $1.2-billion acquisition of SDN startup Nicira, the IT industry has been assaulted with talk of software-defined storage, software-defined compute, software-defined data centers and, well, software-defined anything.

Yet for all the talk, software-defined is real. Software-defined refers to the abstraction of the functionality of some traditional data center hardware component such as a networking switch or storage array into software, adding some type of orchestration and automation, and making it available to applications via APIs -- either open source or proprietary -- to let those applications better control the functionality.

Turn the page to get a taste of the software-defined movement, starting with a look at what could happen to hardware vendors as well as a who's who in the industry.

Proprietary Hardware Or Generic Servers?

The adoption of a software-defined environment offers customers and developers better control over how compute, storage, networking, security and other resources are used by applications, and automates the allocation of those resources. The big question is, will those data center resources be based on generic white-box-like servers, or on the proprietary hardware that currently make up IT infrastructures?

In today's hardware-defined world, the functionality of a storage array or a networking switch is defined by the software, which is likely running on industry-standard servers. That has software-focused startups in the software-defined world developing alternative solutions that can be run on any low-cost, no-name servers.

More traditional hardware vendors, which recognize that customers will be attracted to the flexibility and automation offered by software-defined environments, counter that their hardware is optimized for their software stack, and therefore should not be written off.

VMware And The Software-Defined Data Center

VMware has taken the spotlight in the push toward what it calls the software-defined data center, and is supported by many of those developing storage, networking and other data center technology that takes proprietary hardware out of the picture.

In the software-defined data center, most if not all data center infrastructure functionality could be defined in software running on racks of generic servers, and if carried out to its extreme could one day see a data center running a business' operations and private clouds with no proprietary hardware.

VMware, known for its tradition of partnering with all the top IT vendors including archrivals of its parent company EMC, says that its vision is not aimed at cutting out proprietary hardware, and that it leaves the door wide open for customers to choose their IT infrastructure.

System Vendors Push Back

For traditional system vendors Hewlett-Packard, IBM, Dell and Cisco, the idea that storage, networking and other functions could be defined by upstarts in software-only technology and run on generic server hardware is a big threat to their business models, which depend on selling those functions tied to their software.

The system vendors traditionally have been going in the opposite direction of software-defined environments with the development of converged infrastructures, which tie server, hardware, networking and even applications into integrated systems managed by a single pane of glass. System vendors will tell you this optimizes performance and manageability in a way software-defined solutions cannot do.

However, those vendors realize that software-defined creates among customers the idea that hardware is a commodity. Consequently, they're all developing software to present an open-source interface to let applications do some of the management.

Software-Defined Networking: The Startups

Software-defined networking, or SDN, abstracts all or part of the function of networking switches and routers into software, which can then be used by applications to orchestrate and automate the management of networks.

For many startups, SDN represents a chance to either build an open-source networking layer on top of existing networks or replace existing networking gear with software running on generic hardware, in either case challenging established networking vendors.

CRN has identified a number of SDN startups to watch, including Big Switch Networks, one of the most-talked-about startups in this space, and Insiemi, which was started with funding from Cisco and could some day be acquired by that company.

Software-Defined Networking: The Incumbents

SDN, however, is not just a startup play. Nearly all the incumbent hardware vendors including Cisco, HP and Dell recognize that customers and developers will want to adopt technology that lets applications have better access and manage networking resources. As a result, they have pretty much adopted OpenFlow as a standard protocol to allow applications access to their networking gear features.

However, the hardware vendors insist that open-source technology cannot access or take advantage of all the services provided by their gear, and so in parallel to OpenFlow they are still developing their proprietary APIs as well.

Most of the hardware vendors also joined the Linux Foundation's OpenDaylight Project for developing a common platform for sending APIs to applications that enable those applications to work with multiple SDN protocols including OpenFlow, other standard protocols, and networking vendor-specific interfaces.

Software-Defined Storage: The Startups

Whether the term "software-defined storage" is descriptive of a new storage trend or a clever way to take advantage of the better-known "software-defined networking" moniker, is subject to debate. However, it is quickly catching on as a way to describe a software layer that provides storage services, including such functions as deduplication, replication, snapshots and thin provisioning, using industry-standard server hardware.

Unlike SDN, where many of the startups are building technologies that add open-source orchestration and automation to existing networks, the software-defined storage startups are out to replace traditional storage hardware with software running on generic servers.

Startups such as SwiftStack, Basho and Inktank are the primary developers of open-source storage technologies. Other software-only storage developers include ScaleIO, Jeda Networks and Zadara Storage; they develop software-only systems that can be part of a software-defined environment.

Software-Defined Storage: The Incumbents

While startups are trying to take center stage in the software-defined storage market, traditional storage hardware vendors are fighting back.

Like the startups, the hardware vendors are taking a variety of approaches to software-defined storage. Hewlett-Packard, for instance, says its Virtual Storage Array (VSA) product already offers all the capabilities of at least its definition of software-defined storage. EMC is developing technology that will allow it to put an open-source-focused overlay over multivendor storage hardware to add the management and automation layer.

Meanwhile, more established storage software vendors such as Coraid and DataCore have introduced software-defined storage products, and flash storage acceleration technology developer Fusion-io recently acquired ID7, the commercial support organization of the open-source SCST Linux storage subsystem.