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					             Modern Storage Network Technology and Storage Virtualization:
             New Advantages, Barriers to Acceptance, and Possible Solutions

Michael Spenser, School of Business, Auburn University Montgomery, Montgomery, AL 36124
                         (334) 244-3482, spencermike7@gmail.com

  Bob Gehling, School of Business, Auburn University Montgomery, Montgomery, AL 36124
                            (334) 244-3482, bgehling@aum.edu


                                          ABSTRACT

This paper addresses the growing use of virtualized storage and storage network technology by
organizations to manage growing amounts of data.

                                       INTRODUCTION

There is no question that the requirements of data management, from personal to enterprise level,
have exploded in recent years. According to an EMC forecast of overall data growth, the overall
size of digital universe in 2007 was 281 exabytes, or 281 billion gigabytes [3]. The study also
reported that enterprises are responsible for the security, privacy, reliability, and compliance of
85% of the digital universe. In order to meet the growing demand for storage capacity and
availability, storage area networks have emerged to provide an attached storage solution to meet
these needs.

Initially, the early adoption rate of storage area network technology was very slow and
experienced difficulty in meeting the full potential of centralized storage due in part to “most
components in SANs, despite vendors’ interoperability claims to the contrary, have a tough time
working with products from multiple vendors” [6]. Thus, initial adoption of new data storage
technologies yielded many of the limitations, benefits, and similar problems of normal direct
attached storage. Examples of this included loss of scalability (due to hardware conflicts and an
increase in complexity, such as new hardware additions from different vendors), inability to pool
capacity, and complexity barriers hindering centralized management.

As virtualization applications gained effectiveness in unlocking the potential of storage
networks, the virtualization and data storage relationship yielded the true benefits in adoption
and management of storage technologies. This relationship allowed the clustering of data
storage, implementation of better provisioning strategies, and gains in true utilization of an
entity’s IT resources. Although both technologies are still relatively new, the convergence of
storage virtualization and storage area networks provide a solution to the growing storage
problems of many enterprise environments. Though adoption and implementation of modern
storage strategies has been slowed by the individual difficulties associated with both
technologies and new issues created by their combination, virtualized storage environments are
finally becoming positioned for mainstream adoption by enterprise organizations. As reported
by some industry observers, by 2009, 50% of those enterprises expect to adopt storage
virtualization [4]. The new world of data storage administration in realization of its capabilities
creates new strengths and weaknesses in storage administration that are now beginning to
emerge. The convergence of storage virtualization with dedicated storage networks not only
provides a much needed solution to the growing worldwide data storage gap, but also exposes
problems that hinder full realization of their potential in full utilization as an IT resource and as a
sustainable growing industry.

Beneficial Attributes of the Storage Network/Storage Virtualization Relationship

The “storage management gap” - or storage management capability versus the total data to be
managed - from an overall industry standpoint, has continued to widen since the birth of recent
data storage technologies over the last decade. As the total data that had to be managed
increased at a faster rate than that of the average management capability, the gap growth rate
slowed from 2007 to 2008 [7]. It could be inferred that the gap itself, although still existent, has
begun to shrink due to the relationship between storage technologies and storage virtualization
offering new solutions to a constantly growing problem.

While virtualization generalized is not a new concept, storage virtualization is quickly becoming
less theoretical in nature. Its growth could partially be characterized by server virtualization, a
technology that has been widely accepted and employed in IT environments now for many years.
As reported by Neeraj Gandhi (2008), where modern storage technologies have experienced a
higher rate of adoption, “it is server virtualization that drives storage virtualization. Collectively
though, both of them are aimed at better utilization of the available resources, reducing
complexity and increasing productivity.” In other words, not only do the two technologies
complement each other, they need one another to fully utilize the potential of each to accomplish
shared goals in hosting a number of virtual servers in a large storage environment of a SAN, a
greater number of virtual servers can be deployed securely and management can be simplified.
Storage virtualization in an enterprise data center allows for flexibility and better provisioning of
resources for not only physical servers, but provides a better planning, implementation, and
security solution to be used by the organization.

The grown in unstructured data, such as large media files, have been a driving force in adopting
modern ways to manage, deduplicate, safely store, and move the large media files that are now
commonplace in the enterprise environment. An example of tackling this problem is the use of
clustered storage systems for virtualized storage with storage area networks to provide high
speed connections between hosts and disks. For instance, in an example presented by
Government Computer News, NASA and the Department of Defense currently films and
produces multiple terabyte media files for spacecraft and missile intercept missions for study and
research. Media files and digital content of that magnitude simply cannot be supported by
traditional data storage methods.

To solve this problem, a clustered storage system was used in conjunction with an iSCSI SAN
that provided high speed connections and simultaneous shared access to the data store. This
approach allows users to add more storage and then have multiple clients access that same
storage pool. Rutell Yasin (2007) reported that the advantage of this approach is that you have a
single copy of the data and you have multiple parts of the workflow working on the same data.
In this situation, virtualized storage not only enables the movement and management of
extremely large files containing unstructured data, but also provides hosting and resource
utilization that can be simplified through the storage virtualization-SAN relationship.

To properly provision (allocate) storage space in an enterprise data solution, a clear picture of
must be formed in order to properly assess the needs and limits of data resources to effectively
meet the needs of an organization. Previously, the costly approach of fat provisioning, where
data storage space is allocated beyond current needs in anticipation of future storage
requirements, was often employed. The inability to combine storage resources, often due to
interoperability and compatibility issues in heterogeneous equipment approaches, complicated
the abilities of data administrators to formulate this clear picture. Fat provisioning also proved
costly and poorly utilized available storage resources. Through the combination of storage
virtualization with their storage resources, many organizations are implementing thin
provisioning throughout their storage system to take better advantage and gain better utilization
of these resources. Through the SAN-storage virtualization relationship, resources are better
managed and scaled in accordance to business need better than without the combination.

With recent disasters such as Hurricane Katrina and the recent record floods in Kansas and Iowa,
the need for contingency planning and implementation has quickly become a reality in order to
achieve business continuity. During the recent floods in Iowa, many businesses failed to
effectively plan for data recovery in the face of a catastrophic event. An example would be in
Cedar Falls, Iowa, and the number of businesses who did not integrate redundant off-site storage
of data and implement remote access of a secondary virtualized storage environment within their
contingency planning. One data center in Cedar Falls that did have natural disaster safeguards in
place became the primary provider for business continuity and access of data for organizations
that were not prepared: “Team Technologies, which owns and manages a data center in Cedar
Falls, provided expertise - and, in some cases, sanctuary - for hospitals, a local utility company,
telephone systems and even cable-television service that were able to continue to function
through the chaos that was the Flood of 2008 [8]. Through this, a software development firm in
Cedar Springs, Iowa, experienced no degradation or disruption in continuity in its data
operations during and after the disaster. This company located its data center, which houses 60
servers, source code repositories, and client projects in a third party facility 5.4 miles away from
downtown Cedar Falls. They were also prepared to failover its systems to a secondary facility
outside of Chicago if the floodwaters did cause the 18,000 sq. foot data center to shut down or
lose power for a significant period of time [1]. In other words, modern storage environments
enable organizations to persevere in the face of natural disaster or security threats and achieve
maximum business continuity when combined with effective contingency planning. Without the
combination of virtualization technologies and enterprise storage solutions, total loss of data
assets can be prevented now like never before.

Finally, another great strength gained in the combination of large scale data storage and
virtualization within the environment is tackling one of the greatest issues preventing adoption of
the technology to date: hardware, software, and interoperability conflicts. It is now much easier
for SAN hardware from different manufacturers to achieve simplified administration by
bypassing the interfaces of the individual devices to create a virtual data pool managed by a
single interface. From a scalability and cost perspective, it accomplishes the selling point that
has been pushed by SAN providers all along: a simplified, large scale storage solution that
simplifies the administration of an enterprise environment’s data assets. This returns purchasing
power back to the data administrator without forcing the hardware requirement of purchasing
from a single manufacturer. It is now possible to host a cluster of virtual web servers, production
database servers, and provisioned storage space for multiple business areas under the same
umbrella in a much easier manor. With the data storage technology and storage virtualization,
the combinations of manageable, large scale modern storage is no longer a prospect of the future;
it is now possible and a reality.

Barriers and Fears Hindering Utilization & Adoption of the Data Storage/Storage
Virtualization Relationship

Although there are many reasons that adoption of virtualization and storage area networks is now
a cost effective and realistic solution to meeting the storage challenges faced in many enterprise
environments, there are still problems and barriers to adoption that hinder widespread acceptance
of the two technologies. With advances and gains in the modern storage field growing almost
daily, combination and implementation of storage virtualization and large scale storage systems
is still relatively new. Storage requirements, in their own right, have accelerated at such an
alarming rate that some IT managers are “caught off guard” in identifying and accepting realistic
storage needs. With server virtualization now facing dawning security threats to exploit flaws in
software, virtualized storage volumes face the possibility of dealing with the spread of malicious
attacks within a storage network. In addition to the inherent compatibility difficulties of
complex storage systems such as heterogeneous fiber mesh SANs, more frustration can emerge
as some interfaces and software gain popularity and deny compatibility with competitors to
protect proprietary interests.

Furthermore, with the rapid growth of data technologies and conventional philosophy of network
storage needs merely being another part of network administration, many organizations are left
with dependency on service providers and vendors to implement solutions and conduct
administration of data operations. With competition within all segments of the storage market so
fierce (with declining investor faith in many respects), it’s hard to determine exactly what is fact
and what is spin. To make matters worse, storage administrators are new specialists that
organizations have difficulty in locating, recruiting, and training.

Security Risks in the New World of Virtualized Storage

Server virtualization and storage virtualization are separate things; however, if server
virtualization is one of the primary driving factors in advances for storage virtualization, security
weaknesses in one could severely impact the other. In addition, a virtualized storage environment
comprising of separate physical storage arrays could theoretically serve as a “bridge” for an
attack to propagate throughout other parts or even an entire virtual volume. Given the popularity
of virtualized servers on shared storage, security concerns for virtualized storage on storage area
networks should take the flaws of individual virtual servers into consideration as a likely point of
entry and launch pad for a possible attack.

One possible exploit comes from the tools that simply virtual network administration on storage
volumes: virtual machine monitoring software itself. Vijayan (2007) reported that virtual
machine monitors use consoles to manage the resources of the hardware hosting the virtual
machines and to act as an interface between the hardware and various virtual machines hosted on
it. He indicated that depending on the interaction between monitoring software and a storage
virtualization software solution, attacks on virtual machines could essentially be the “skeleton
key” to unlock the possibilities of a larger security threat.

An example of a way that attacks can utilize virtualization engines to spread throughout a storage
environment can be seen in one of the industry leaders in all things virtualization: VMWare.
With increasing pressures for storage hardware manufacturers to support virtualization, virtual
storage controllers are being manufactured to support VMWare’s Infrastructure software
platform. In combination with VMWare’s other virtualization products that could all share
similar vulnerability issues, preference to use VMWare for all virtualization needs could extend
exposure to a possible threat. “The VMWare platform, with its rights and privileges to the host
operating system and hardware, makes a tempting target for malware writers… That makes it a
question of when—not if—virtual machine specific malware will start jumping between virtual
machines, down the stack to the host operating system or even to the virtual machine monitor
layer” [9].

Another key point in such vulnerability is the monitoring software usually sits just one level
above the hardware and can be used to launch virtually undetectable attacks against the operating
system and application layers above it [11]. In other words, monitoring software deployed over a
large virtual storage volume might open doors for large-scale attacks that may prove difficult to
detect. Although only a single scenario in an infinite arena of possibilities, it is a snapshot of
how the simplification gained through the SAN-virtual storage relationship increases concerns
for storage and security administration.

Such attacks are unlikely in most environments, as there are a number of defense mechanisms or
safeguards (depending upon the design of each individual storage solution) that can prevent
many security exploitations in the storage environment. Virtual switches can be deployed
between virtual servers, as well as strategic decisions on what virtualized elements exist inside
and outside the DMZ of a virtual network to prevent many exploits on devices within specific
LUNs. Furthermore, in a fibre channel environment, LUN masking and zoning strategies can
isolate vulnerable volumes to isolate attacks. However, with more pressure for utilization of
storage virtualization in storage area network technology and compromises made to
accommodate for its advantages (such as choosing soft zoning in a heterogeneous fibre channel
storage environment to achieve interconnectivity), future security threats could add
consequences and complication in pursuing virtualized volumes. Any security threat, theoretical
or proven, can prevent adoption and utilization of modern storage solutions by organizations
unwilling to fully commit to good security practices and expertise required for proper
deployment of either virtual storage or dedicated storage networks.

Economic and Industry Barriers to Mainstream Virtualized Storage Acceptance

Investor faith in data storage products and services seems to be mixed. Excluding market factors
that influence stock prices for each individual firm, hardware vendors that manufacture storage
products (such as HP, Dell, IBM, Hitachi, EMC, etc.) have overall experienced greater
profitability and growth from the year 2000 to present. It could be inferred that the effect of
storage virtualization to deliver better value from SAN technology has pulled storage through the
early adoption phase and into better positioning for mainstream acceptance. However, other
hardware vendors, virtualization firms, and service providers have experienced very mixed
results. Virtualization software developers, for example, are highly competitive with one another
to gain market share. In regards to adoption and utilization of storage technologies and storage
virtualization, two factors can be seen as barriers: value creation achieved in using large scale
storage and ethical and political dilemmas in upper management of storage technology firms
creating negative impact upon the entire industry.

In the early adoption stage of storage area networks, vendors promised things that the technology
aimed to achieve but had varying degrees of difficulty in turning into a beneficial reality:
simplified, secure, cost effective, and centralized data management. Since then, these goals are
now achievable with the combination of virtualization solutions implemented into a firm’s
overall data infrastructure. Although adoption of storage technologies has increased, it is still
moving at a slow rate as a lack of understanding still creates the fear of the unknown.
Furthermore, in a business making the purchasing decision, relevance is placed on the bottom
line benefits, return on investment, and business need for these solutions. All stakeholders in
storage technologies, from small NAS and FAN vendors to the sellers of large scale virtualized
fibre channel or iSCSI SANs, need to deliver factual value creation benefits and eliminate
industry “fear of the unknown.” Currently, this is not occurring in many situations. Staimer
(2005) reported that a “few vendors actually articulate clear, quantifiable value propositions for
their products… Most vendors assume their customers will understand the value proposition
intuitively or that it does not matter.” The need for a general understanding of the value in
buying into these modern technologies does matter when an economic decision maker within a
firm makes the decision to purchase.

A second negative influence that could hinder adoption is the ethical and political dilemmas
occurring in the boardrooms of storage firms. From an ethical standpoint, many service providers
and vendors have encountered ethical issues in the boardroom. For example, Brocade is an
industry leader in fibre channel switching technologies that are used heavily in mesh fibre
storage area networks. In 2007, its former CEO and other executives were found guilty of stock
options fraud (thus painting a negative picture on the firm). Another example would be
VMWare, in which it lost some investor faith in what some may call a mysterious resignation of
its CEO and cofounder, Dianne Green, in early July of this year. Stock price fell approximately
30% in response.

Boardroom shakeups, lacking delivery in communication of the benefits of adoption of storage
technologies, and ethically questionable business practices further cloud the confusion in the
decision making process of IT and business managers alike. Although the long-term benefit
usually outweighs the high initial cost of implementing a large scale storage solution (especially
during today’s recession and volatile economic climate), many factors come to play in
establishment of the vendor-customer relationship. While gains are being made now at a faster
pace than ever before, all players in storage and virtualization technologies need to consider that
all facets of modern storage are still in an early adoption stage and at the verge of reaching
mainstream acceptance. It is possible to remain an individually competitive firm in earning a
“piece of the pie” in the technology market, while pursuing professional and ethically
responsibility in that everyone involved in the new world of storage is a stakeholder.

The Standardization and Professional Barriers to Utilization of the Storage Networking-
Storage Virtualization Relationship

Data storage administration, with advances in utilizing storage networks and storage
virtualization, has emerged as a specialized role in the enterprise storage environment. Proof of
this fact can be seen in the rapid increase of scale in all things storage, the very complicated
methodologies and changes in elements available in data administration today, and the need for
understanding for the broad spectrum of possibilities and available products and uses for storage
solutions that can meet the needs to protect and manage hardware and data assets of an
enterprise. In some ways, the rapid growth of and need for storage technologies has increased
this confusion faster than the identification and understanding of many IT departments within
organizations. Three factors can help visualize some of the professional and standardization
barriers to understanding and implementing modern storage technologies: the lack of industry
standards and conformity to them by stakeholders, internal conflicts preventing the empowering
of data administrators within a firm, and the slow increase of professional and specialized data
administrators in the labor market.

Storage Networking Industry Association (SNIA) is working to create a good foundation for
which data storage standards can be built. However, it still faces a very difficult challenge in
gaining the support and strength it needs to advance acceptance of standardization. In describing
the standards battle, [5] reported that part of the problem: “As with many fast evolving
industries, little attention has been paid to standards, resulting in a flood of proprietary
implementations.” In other words, the industry has grown so quickly that the structure of
standards beneficial to other IT industries have been replaced in the storage arena by a high
expectation of support and use of specific vendor features. Gsoedl [5] also reported that in
addition to slowly evolving standards, the adoption of existing standards has been hampered by
incomplete implementations of SMI-S and vendors trying to protect their turfs. With such
vendor protectionism and resistance to adoption of standards, interoperability and advancement
of storage technologies as a whole are hindered.

Another important factor hindering full utilization of storage technologies can be identified in the
lack of realization that the storage administrator (or storage administration team) is truly a
specialized role that has a primary goal of fully utilizing the advantages by implementing their
own storage strategy, and having the ability to make a business’ storage strategy efficient,
effective, and secure. In other words, IT departments may not fully understand the need to
empower their storage administrator and relinquish control they once felt entitled to under older
conventional wisdom. In a special report on Enterprise Storage Forum:

       “In [a] Gartner poll, while 70 percent of respondents had a dedicated storage team
       in place, the teams were typically not empowered to address broad storage issues,
       nor were they able to deliver the potential benefits…Departments and lines of
       business are reluctant to yield control of their environments to meet broad cross-
       enterprise storage initiatives. The brittleness and complexity of traditional and
       legacy storage infrastructures has taught them that desired service levels and cost
       optimization are compromised by attempting to ‘share’ these infrastructures with
       others, perpetuating silos of infrastructure” [12]

In not recognizing the need of a dedicated storage administrator or data storage administration
team, organizations can quickly lose benefits reaped by adoption and utilization of a storage
solution. Also, a data administrator’s ability to properly provision storage resources to best fit an
organization’s need greatly diminishes when having to conform to the pressures and will of other
IT departments’ requests for their allocated stake in the overall storage space. This also strains
the administrator’s ability to enforce data deduplication, and greatly reduces the ability to gain
the simplification in managing storage resources.

A third need in the storage industry (and in battling the storage gap in general) is the creation of
storage administrators that are educated, trained, and specialized to manage and implement
storage resources. Not only is it important to accept the need to specialized storage
administrators, but also for a firm to have their own in-house storage expertise in order to
implement a storage solution that best fits the organization’s need. With a global shortage in
storage administrators and individuals with the variety of disciplines needed for their roles, in-
house storage expertise is quickly becoming more difficult to obtain. Thus, organizations are
forced to turn to vendors and service providers for storage solutions, which can diminish
purchasing power and overall control of a company’s own IT department. All stakeholders in
the storage industry, from manufacturers to individual IT managers, face the growing need in
educating the public on the benefits and knowledge of modern storage technologies to break
down communication barriers among one another caused by confusion in rapid growth of the
industry.

Breaking Down the Walls: Overcoming Barriers to Acceptance of Storage Networking and
Storage Virtualization

Although there are identifiable fears and gaps in acceptance and understanding of modern
storage needs and solutions, new opportunities are rising to diminish these threats. However, in
order to battle these shortcomings, all stakeholders in storage technologies need to contribute to
the development of standards and creation of resources to enable full utilization, adoption, and
beneficial growth of large scale storage environments. Without adherence to standards and
communication among storage stakeholders, the gap of understanding and productive industry
growth will continue to grow out of control.

One such example can be seen in the empowerment, support, and adherence to SNIA itself. With
industry leaders now providing support to the organization, vendor-neutral development and
achievement of standards is now beginning to emerge. SNIA certifications help develop
expertise in the field of storage technology, while guiding professional development to create
qualified data professionals. Now with a worldwide scope and reach, SNIA has increased
communications across the storage industry and strengthened the areas of storage technology and
virtualization while providing valuable resources to all industry stakeholders through education
and establishment of vender-neutral programs.
Currently, there are very few actual dedicated data storage academic programs to develop
interest and professionals for data storage technologies and storage virtualization at both the two
and four year traditional education level. Understanding of storage area networks, storage
virtualization, and important industry trends is something difficult to groom and educate in the
current landscape of information technology. There are a wide variety of possible solutions and
methods in order to build awareness in the storage industry; however, a successful example of
how to overcome many of the barriers and challenges faced by modern storage technologies can
be found in a case study of Auburn University of Montgomery in Montgomery, Alabama.

Unisys Corporation is a successful storage technology provider in the central Alabama region.
Unisys holds several defense, government, and commercial contracts in the area as a service
provider for data storage solutions. As the difficulty in obtaining trained data storage
professionals regionally became apparent, steps were made to meet the need of its customers in
developing storage expertise. The Alabama Technology Foundation was formed as an outreach
organization to further the advancement in education of data storage technologies in the region.
Partnered with hardware providers such as Hitachi Data Systems, Hewlett Packard, and EMC,
data storage service contractors such as Unisys, and non profit organizations such as the Armed
Forces Communications and Electronics Association, ATF founded the Data Storage Center of
Excellence at Auburn University Montgomery.

Through this combination of industry stakeholders, funding and equipment has been donated at
the school to produce graduates of a dedicated data storage degree program. Students can
achieve a dedicated academic data storage management degree with a curriculum focusing on the
adherence to SNIA principals, with donated fibre channel storage area network equipment, to
receive a rounded education in storage technologies and storage virtualization to produce
graduates with a modern understanding of the requirements of storage administration. The
Alabama Technology Foundation will then contribute to professional development of graduates
by assisting with job placement with organizational partners to build experience in the arena of
storage technologies. These contributions have brought a understanding of concepts and interest
in storage administration that was once absent in both the business and academic community on
the regional level; thus overcoming many barriers to utilization of storage technologies that will
help meet the storage needs locally and regionally in the future.

                                        CONCLUSION

Storage virtualization has helped storage area network technologies realize the goals of
simplification in storage management that were initially unable to fully be realized due to the
administration conflicts existing in first generation hardware. The relationship between
networked storage and storage virtualization is not only a possibility, but now an industry
accepted reality that is pushing acceptance as a fully realized solution into the IT industry.
Although security risks exist in the rapid acceptance and deployment of virtualization
technologies that may yet be fully identifiable, exposure can be minimized by following sound
security practices to prevent exposure to attack.

However, fighting the storage gap with modern and simplified virtualized enterprise storage is
something that everyone has a stake in. The industry as a whole, while fighting to obtain
competitive advantage within their respective markets, must also invest in the education,
standardization, and proliferation of modern storage solutions to sustain the industry as a whole.
Storage administrators must not only be trained to identify the best solution to fit their in-house
needs, but also be abreast of all the inherent risks and rewards in deployment and proper
management of their data storage environment. By conforming to industry-wide accepted SNIA
standards, with industry stakeholders pursuing establishment of those standards over a
proprietary-centric approach, virtualized storage can become more accessible to all IT
organizations with a need to securely and effectively manage their data assets with specialized
and empowered storage administration professionals. Therefore, by having a view of the “bigger
picture” of threats to mainstream acceptance of large and simplified mass storage, all industry
stakeholders can gain from having an interest in sustaining the advancement of the industry as a
whole. Networked storage and storage virtualization not only influence growth of one another;
instead, they are now complimentary technologies that coexist effectively.

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