Ibm TS7650G PROTECTIER User Manual

P R O D U C T P R O F I L E

Evaluating Enterprise-Class VTLs: The IBM System Storage

TS7650G ProtecTIER De-duplication Gateway

September 2008

Increasingly stringent service level agreements (SLAs) are putting significant
pressure on large enterprises to address backup window, recovery point
objective (RPO), recovery time objective (RTO), and recovery reliability issues.
While the use of disk storage technology offers clear functional advantages for

resolving these issues, disk’s high cost has been an impediment to widescale
deployment in the data protection domain of the enterprise data center. Now that storage
capacity optimization (SCO) technologies like single instancing, data de-duplication, and
compression are available to reduce the amount of raw storage capacity required to store a
given amount of data, the $/GB costs for disk-based secondary storage can be reduced by 10 to
20 times. Virtual tape technology, disk-based storage subsystems that appear to backup
software as tape drives or libraries, are one of the most popular ways to integrate disk into a
pre-existing data protection infrastructure because they require very little change to existing
backup and restore processes. While virtual tape libraries (VTLs) are interesting, SCO VTLs
that leverage data de-duplication and other related technologies are compelling.

Given high data growth rates, stringent SLAs for data protection, and the need to contain
spending, enterprise customers really need to take a look at SCO technologies. Taneja Group
predicts that large enterprises will rapidly move to SCO VTLs over the next 1-2 years while the
market for non-SCO VTLs (VTLs that do not have integrated SCO technologies) dwindles
rapidly. Data growth rates in the 50% - 60% range will be pushing this transition as much as
will the clear cost advantages that SCO VTLs offer over non-SCO VTLs. While SCO is a key
requirement, performance remains the number one need of the enterprise data protection
environment. After all, if the SLA for completing the day’s backup cannot be met, all other
criteria are moot. This has significant implications for vendors of SCO VTLs. Their solutions
must provide the capacity optimization that the enterprise customer demands, while enabling
enterprise-class performance. Vendors that can provide both efficient SCO technology and
enterprise class performance offer a very compelling value proposition.

In this Product Profile, we discuss the criteria we recommend be used to compare and contrast
enterprise-class SCO VTL solutions from different vendors, and then evaluate how the IBM
System Storage TS7650G ProtecTIER De-duplication Gateway performs against these criteria.
The TS7650G, IBM’s first offering based on technology from the April 2008 acquisition of
Diligent Technologies, supports very high single system throughput, multiple PBs of usable
capacity, and optional clustering with support for a global de-duplication repository - all
important considerations for enterprise SCO VTL prospects.

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The Inevitability of Disk-Based
Data Protection

Disk is in widespread use as a part of the
data protection infrastructure of many large
enterprises. Evolving business and
regulatory mandates are imposing stringent
SLAs on these organizations, pushing them
to address backup window, RPO, RTO, and
recovery reliability issues, and disk has a lot
to offer in these areas. Technologies such as
VTLs have made the integration of disk into
existing data protection environments a very
operationally viable option.

Cost has historically been the single biggest
obstacle to integrating disk into existing data
protection infrastructures in a widespread
fashion, but the availability of SCO
technologies such as single instancing, data
de-duplication, and compression have
brought the $/GB costs for usable disk
capacity down significantly. SCO-based
solutions first became available in 2004, and
the SCO market hit $237M in revenue in

2007. Over the next five years, we expect
revenue in the SCO space to surpass $2.2B,
with the largest single market sub-segment
being SCO VTLs (source: Taneja Group Next
Generation Data Protection Emerging
Markets Forecast September 2008). If you
are not using disk for data protection
purposes today, and you are feeling some
pressure around backup window, RPO, RTO,
or recovery reliability, you need to take
another look at SCO VTLs. It is our opinion
that within 1-2 years, SCO VTLs will be in
widespread use throughout the enterprise.
With data expected to continue to grow at
50% - 60% a year, the economics of SCO
technology are just too compelling to ignore.

A Brief Primer on SCO

Taneja Group has chosen the term
SCO to apply to the range of technologies
that are used today to minimize the amount
of raw storage capacity required to store a
given amount of data. Data de-duplication is
a common term in use by vendors, but this
term really only describes one set of
algorithms used to capacity optimize storage.
And many vendors of de-duplication use it
along with other technologies, such as
compression, in a multi-step process used to
achieve the end result. That said, de­duplication is the primary technology that
enables solutions to reach dramatic capacity
optimized ratios such as 20:1 or more. Given
the focus and attention on de-duplication ­as well as the fact that it is at the heart of
IBM’s TS7650G - let’s take a closer look.

At their most basic level, data de-duplication
technologies break data down into smaller
recognizable pieces (ie. elements) and then
look for redundancy. As elements come into
the system, they are compared against an
index which holds a list of elements that are
already stored in the system. When an
incoming element is found to be a copy of an
element that is already stored in the system,
the new element is eliminated and replaced
by a pointer to the reference element. In
secondary storage environments like backup
where backed up data may only change 3-5%
or less per day, there is a significant amount
of redundancy that can be identified and
removed (a 5% change rate implies a 95%
data redundancy rate!). De-duplication
algorithms can operate at the file level (this is
also referred to as single instancing) or at the
sub-file level. Sub-file level de-duplication

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tends to produce higher data reduction
ratios. Looking across vendor offerings in
the market today, it is not unreasonable to
achieve data reduction ratios against
secondary storage like backup data sets of
10:1 to 20:1 or greater over time.

To provide an example of how de-duplication
performs in practice in backup applications,
let’s take an example. Assume a new data set
that has never before been backed up. On
day 1, it is backed up to disk and de­duplicated (this may occur during the
backup or after the backup, but more on that
later). On day 2, the data set is once again
backed up to disk, but as de-duplication is
applied, it can now look at both backups to
find common elements. The data reduction
ratio achieved on day 2 is very likely to be
higher than that achieved on day 1,
particularly if the backed up data has not
changed much in the 24 hour period. If we
assume that 30 days of backups are retained
on disk, then it is very likely that there is a lot
of redundant data that can be removed and
replaced with pointers. The factors affecting
data reduction ratios in backup include the
change rate of data (day to day), the number
of days of retained backups, and the specific
SCO technology in use.

SCO Approaches and Architectures

SCO can be deployed either at the source
(backup client) or at the target (backup
target). Performing the capacity
optimization work requires CPU cycles, so
where it is performed may have a
performance impact that needs to be
evaluated. Source-based SCO typically
leverages resources on the backup client to

perform the work, which may impact backup
and/or application performance, but it does
minimize the amount of data that has to be
sent across a network to complete the
backup. Source-based SCO may offer certain
advantages in remote office back office
(ROBO) backup environments, but tends to
be targeted at environments where each
backup client does not have a lot of data.

Target-based SCO presents a backup target,
often through a VTL interface, and leverages
resources on an appliance or a storage
subsystem to perform the work. Target­based SCO supports much greater
throughput than source-based, and tends to
be targeted for use in enterprise
environments to handle large backup
volumes per client. Target-based SCO can
offer the opportunity to much more
efficiently leverage a global data de­duplication repository during the capacity
optimization process than source-based SCO
can. Vendors that support a global
repository can often offer higher data
reduction ratios than those that do not since
they can perform the redundancy
identification and elimination across a much
larger number of backup clients.

Capacity optimization can be performed
through either an in-line or a post­processing approach. In-line processing
performs the capacity optimization work as it
is writing data to the backup target. Post­processing allows the data to be first written
to the backup target, and then through a
separate process picks this data back up and
runs it through the capacity optimization
process. The operative metric for an end
user, assuming that you want your backups

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in capacity optimized form, is the amount of
time it takes to both ingest the backup and to
perform the capacity optimization, not just
the time it takes to ingest the backup.

This dichotomy (in-line vs post processing)
has some key implications on overall system
performance that may not be entirely
evident. When an in-line vendor quotes a
throughput number, that is the single
number necessary to evaluate how long it
takes to complete the backup and process the
data into capacity optimized form, at which
point it is ready for any further processing
(e.g. 600MB/sec can process roughly

2.16TB/hour). When a post-processing
vendor quotes throughput, that generally
refers to how long it takes to ingest the data
and does not include the post-processing
time necessary to capacity optimize it (e.g.
600MB/sec can ingest 2.16TB/hr but
additional time will be required to perform
post-processing). To truly understand if a
post-processing approach can meet your
backup windows, you need to evaluate the
total time required to both ingest the backup
and to perform the post-processing. Post­processing vendors may argue that since the
post-processing is de-coupled from the
backup, it doesn’t matter how long it takes.
In some environments, that may be true but
if you have an 8 hour window to complete
your backups and capacity optimize them
before you clone data to tapes, or replicate
your backup sets to a remote site for DR
purposes, and you cannot complete the
backup ingest and the post-processing within
that 8 hour window, then the post­processing approach will impact your DR
RPO.

Without a doubt, in-line approaches require
less overall physical storage capacity than
post-process approaches. For a given
environment exhibiting a 10:1 capacity
optimization ratio, the system will write
100GB of data for every 1TB it backs up. A
post-process method will need to write that
1TB to disk first, then cycle it through post­processing, eventually shrinking the storage
required to store that backup to 100GB.
Thus, post-processing systems must
maintain spare capacity to allow for the
initial ingest of data prior to the de­duplication process. Post-processing
products clearly require more capacity for a
given environment than in-line solutions to
allow for this buffer, but the actual amount
will vary based on the specific post­processing approach being used.

Post-processing approaches introduce
additional time before a capacity optimized
backup is ready for further processing, such
as cloning to tape, distributing electronically
to a DR site, etc. If additional time and
capacity are available, then you may be
indifferent between the two approaches, but
if they are not, then this is something to
consider when evaluating solutions. Note
that some post-processing vendors allow the
post-processing to be started against a
particular backup job before it completes,
thereby reducing both the capacity and time
requirements that would otherwise be
associated with approaches which perform
these operations sequentially. In-line
approaches, however, will generally complete
the overall backup processing (ingestion +
capacity optimization) faster than post­processing approaches since they complete
their work in a single pass.

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What To Look For In A SCO VTL

First, you need to understand what your
backup issues are and how you prioritize
them. If you’re like most enterprises, they
will be most of the following: backup
window, RPO, RTO, recovery reliability,
solution cost, and offsite data storage
requirements (whether by tape transport or
replication). Other considerations include
integration issues with your existing data
protection infrastructure, whether you’re
targeting ROBO or data center environments,
and what the quantity of data is that you will
be dealing with over the lifetime of the
solution. Once these issues have been
understood, it’s time to take a look at the
technology options. Over the last several
years, we have talked with hundreds of end
users that have deployed SCO VTL
technology, and that input, combined with
our take on the developing trends in data
protection, has led us to define the following
criteria for evaluating SCO VTL solutions:

Performance. Assuming you want the
data in capacity optimized form, the
operative issue here is how fast you will be
able to complete the backups and get the data
into its capacity optimized form so that it is
ready to be used for any additional
processing, such as tape cloning and/or
replication to a remote site. Whether you
choose an in-line or a post-process approach
may impact backup ingest time, but you still
need to understand the total time required to
ingest and capacity optimize the backup to
ensure that you will have sufficient time to
meet any further backup processing
requirements.

If your target is to complete daily backup
activities within 8 hours, and you have
roughly 26TB of data that will have to be
transferred each day to perform the backups,
then an in-line solution would need to
process data at about 900MB/sec on a
sustained basis to meet this requirement.
With a post-process solution, you would
need to be able to ingest the backup and
complete the separate SCO processing within
that same 8 hour period - a difficult
challenge. To make this calculation, you’ll
need to ask the vendor about the rate at
which data is capacity optimized during
post-processing.

Scalability. There are several issues to
consider here. First, understand what the
base capacity of the system is. Capacity
optimization ratios generally vary across
workloads, but the more base capacity is
supported, the more usable capacity will be
supported. Let’s define some terms here.
Base capacity is the amount of raw capacity
supported after any RAID-based data
protection schemes have been taken into
account. Usable capacity refers to the
amount of storage capacity represented after
any applicable SCO technologies have been
applied against base storage capacity. For
example, a system with 50TB of base
capacity, when used with a workload that can
be capacity optimized at a rate of 10:1, can
store up to 500TB of raw data.

Next, understand what kind of capacity
optimization ratios you can expect to
achieve. If vendors offer a capacity planning
tool that can be run against a target workload
to provide an estimate, then take advantage
of this. If at all possible, test several of the

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technologies that look most promising in
your environment, and don’t just run them
against a single backup. The throughput
performance of various SCO algorithms may
change over time as the indexes grow;
conventional hashing and content-aware
algorithms may actually suffer decreased
throughput once their index has outgrown
main memory capacity (something that often
happens around 20TB of base capacity with
conventional indexing algorithms). In
environments that do weekly full and daily
incremental backups, ratios will generally
improve over time, approaching a steady
state. The daily change rate of your data is a
critical determinant of the ratios you’ll
achieve over time, and if you’re like most
shops your daily rate will vary somewhat.

Finally, understand if the solution you’ve
chosen supports what is called a “global”
repository. Earlier, we stated that some sort
of index is generally referenced as each
element comes into the system.
Architectures that allow multiple SCO VTLs
to reference a single, global repository that
includes all the elements that have been seen
before tends to offer better ratios than
systems that have a single, separately
developed index for each SCO VTL.
Architectures that support global repositories
tend to offer a better growth path as well,
since when the performance capabilities of a
single SCO VTL are outgrown, a new one can
be added and can immediately take
advantage of the index that is already there.

High availability. In today’s 24x7
environments, even secondary data has to be
highly available so that stringent SLAs can be
met. SCO VTLs cannot compromise that

high availability as they are integrated into
existing data protection infrastructures.
Once data is converted into a capacity
optimized form, it is not usable by
applications until it can be re-converted back
into its original form. If there is a failure,
either within a SCO VTL or at the level of the
entire SCO VTL, the data may not be
available. For that reason, it is important to
support high availability solutions that can
ride through single points of failure. High
availability architectures allow maintenance
to be performed on-line as well, further
improving the overall availability of the
environment. Clustered architectures are a
good way to meet this need, and can
contribute to higher overall throughput as
well if a global repository is supported. Look
for support also for various RAID options on
the back end storage to protect against disk
failures.

Reliability. Because SCO VTLs effectively
convert data into an abbreviated form prior
to storing it, there is some conversion risk
that must be evaluated. How does the
system perform the conversion, and what is
the risk of false positives (two elements that
are not exactly alike being identified as
such)? In SCO VTLs that use conventional
hashing methodologies, this risk is called out
as the “hash collision rate.” While nominal
hash collision rates may appear to be low
with conventional systems, if they are going
to be used in enterprise environments that
may be dealing with petabytes of usable
capacity, they need to be evaluated in light of
that level of scale.

When data is read back, it’s important to
verify the accuracy of the conversion process.

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Does the SCO VTL perform data verification
to ensure that any retrieved data, after it is
converted back into its original form, exactly
matches the data that was originally written
by the application? How is this done? Any
system being evaluated for use in an
enterprise environment must offer
independent data verification to ensure
conversion accuracy.

Solution maturity. With a technology like
SCO, there is a learning curve for vendors.
Being further down on the learning curve can
translate directly into better performance,
higher scalability, and improved data
reliability. Look for vendors that have at
least hundreds of systems deployed in
production and can point to a number of
references whose environments look similar
to your own. Large enterprises often look for
very broad support coverage which can
address locations they may have on a
worldwide basis. Larger, more mature
vendors tend to offer better geographical
support coverage than smaller vendors.

IBM’s TS7650G: An Enterprise­Class SCO VTL Solution

In April 2008, IBM announced the
acquisition of Diligent Technologies. With
their in-line SCO VTL gateway, Diligent had
already achieved considerable success,
having established themselves as a leading
SCO VTL vendor to large enterprises. The
IBM acquisition puts the muscle of a trusted
storage supplier behind Diligent’s unique
and innovative ProtecTIER technologies.

IBM’s announcement of the TS7650G
ProtecTIER De-Duplication Gateway in

September 2008 represents the integration
of Diligent’s technology into IBM’s Tape
Systems product portfolio and includes
important new functionality for large
enterprises. With this release, IBM offers
clustering for high availability, supports a
global repository across cluster nodes, and
doubles the sustained single system
throughput of their SCO VTL to almost
1GB/sec – a number that clearly marks them
as the industry leader for in-line, single
system SCO VTL performance today. This is
a familiar position for them however, since
the previous version of the ProtecTIER
technology had the industry’s highest in-line,
single node throughput before it was
superseded by the TS7650G.

The ProtecTIER Technology

The TS7650G is a SCO VTL gateway based on
an IBM System x with 3 GHz, quad core Intel
processors and 32GB RAM, running Red Hat
Linux. Available in two models – a single
node or a dual node cluster – it supports FC
on both the front and back ends and
dedicated Ethernet connections for the
cluster communications. While the gateway
supports heterogeneous storage on the back
end, IBM has specifically qualified their own
storage subsystems, including the DS4000,
DS8000 and IBM XIV storage platforms, as
well as storage subsystems from EMC and
HDS.

HyperFactor is the patent pending de­duplication technology that is used to
perform the capacity optimization. What is
so unique about this technology is that it is
based on an extremely efficient indexing
design that can map up to 1PB of base

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storage in a scant 4GB of RAM. This
supports the TS7650G’s industry leading in­line, single node throughput because element
identification and referencing is all
performed in main memory – no accesses to
disk are required. Competitive indexing
technologies such as hashing and content­aware approaches have much less efficient
mapping algorithms, forcing them to
reference a disk-based index during the
capacity optimization process to map more
than around 20TB of base capacity. This
explains why alternative capacity
optimization technologies generally suffer
decreased throughput as the repository
grows; they run very fast when all the index
references can be handled in main memory,
but once they outgrow the available memory
and must touch disk, reference times can
slow down by two orders of magnitude. This
efficient index mapping design sets
HyperFactor apart, allowing it to scale
linearly for repositories up to 1PB in base
capacity. After HyperFactor completes the
de-duplication process, it then compresses
elements before they are stored.

The Importance of SCO VTL Clustering

With this announcement, IBM is unveiling
gateway clustering along with support for a
global repository. Although today they are
supporting two node configurations, the
architecture is designed to support up to 16
nodes over time, providing a very scalable
growth path for high end customers.
Clustered TS7650Gs present a single VTL
image to backup servers across which single
system throughput can be scaled. Based on
data from ProtecTIER’s installed base, many
of their customers are seeing single node

sustained throughput in the 450MB/sec
range, with peak throughputs topping
600MB/sec. In adding a second node and
supporting a global repository, IBM is
pushing the sustained throughput rate into
the 900MB/sec range, with peak
throughputs even higher. Because the entire
index is mapped into the main memory of
each node, it doesn’t matter which node a
backup stream hits: it will enjoy the same
high level of performance.

When it comes to throughput in clustered
environments, there is an important
distinction between single system and
aggregated throughput. Single system
throughput identifies a throughput number
against a single repository, access to which
may be spread across multiple VTLs and
multiple processing nodes. In the TS7650G’s
case, multiple gateways leverage a global
repository, which makes the single node
throughput number additive as nodes are
added to scale the system. For example, a
single node TS7650G can sustain speeds of
450MB/sec, while a two-node cluster can
sustain 900MB/sec, all while accessing a
single large repository. Other competitors
talk about aggregate throughput numbers for
their clusters, which implies that they do not
support a global repository. In these
products, there is a separate repository for
each “node” so the performance numbers for
each node are not additive. Such products
lead to independent islands of storage, which
limits the capacity optimization ratios to
those achievable by a single node.
Enterprises that are looking to consolidate
their backup sets to improve efficiencies and
reduce management points, necessarily
prefer solutions with high single system

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throughput as opposed to throughput that is
aggregated across several independent
systems.

The introduction of clustering technology
has important implications in the areas of
performance and high availability. As
mentioned above, it allows IBM to increase
their in-line, single node performance lead in
the industry even further. Very high single
system throughput is most important when
customers have newer, higher performance
FC interfaces between the backup servers
and the VTL – just what you’d expect in the
large enterprise environments at which IBM
is targeting the TS7650G.

Availability is another extremely important
consideration in these types of
environments. In two node configurations, a
single node can fail and the remaining node
will immediately begin servicing the entire
workload, although the overall throughput of
the configuration will drop to that of a single
node. The failed node can be replaced on­line and re-integrated into the cluster
without having to disrupt the backup
applications that are writing to the VTL.
Clustering also gives customers additional
flexibility in performing maintenance and
upgrades to cluster nodes, as well as
gracefully expanding cluster size in the
future as larger node counts are supported.
The TS7650G clustering technology supports
both improved performance and availability,
not just improved availability.

Evaluating the IBM TS7650G

How well does the TS7650G perform against
the criteria we identified earlier for

evaluating SCO VTL solutions (performance,
scalability, availability, reliability, solution
maturity)?

Performance. We’ve already reviewed the
TS7650G’s industry-leading in-line, single
node and single system performance
numbers, showing how that is directly
related to IBM’s patent-pending HyperFactor
de-duplication technology. The highly
efficient index design of HyperFactor allows
it to scale up to 1PB of base capacity without
impacting indexing performance, a
considerable problem for competitive
alternatives that are based on hashing or
content-aware algorithms. IBM’s roadmap
includes expanding the solution to a higher
number of nodes over time, which will offer
large enterprises a non-disruptive, long-term
growth path to higher performance.
Competing vendors may offer higher
aggregate throughput today, but single
system throughput is the operative number
for the enterprise data center. What is clear
is that the TS7650G supports the industry’s
highest in-line, single system throughput
performance for a SCO VTL today by a wide
margin.

Scalability. The data growth rates that
most large enterprises are experiencing today
mean that most will be managing at least
hundreds of terabytes of secondary data in
the near future. With ProtecTIER’s ability to
support up to 1PB of raw capacity, the
TS7650G can support multiple petabytes of
usable capacity, depending on the achieved
capacity optimization ratios across the
relevant workloads. Hash-based and
content-aware de-duplication algorithms do
not even come close to the scalability of

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HyperFactor, whose ability to map 1PB of
base capacity in main memory supports
multiple petabytes of usable capacity. The
fact that IBM can scale to this level against a
single, global de-duplication repository is
key: all other things being equal, they will
achieve higher data reduction ratios by using
a global repository than vendors scaling to
the same usable capacity but that spread that
capacity over multiple repositories (one
associated with each SCO VTL appliance).
And the TS7650G’s single node performance
and scalability mean that you can build out
these large configurations with less
hardware, creating simpler, less expensive
configurations. Whether you’re consoli­dating multiple existing backup targets or
creating a single backup target that can scale
to petabytes of capacity, the TS7650G lets
you do this very cost-effectively.

Availability. The introduction of clustering
not only doubles single system performance
but also addresses the enterprise
requirement for higher availability. IBM’s
clustering technology provides a highly
available environment that can tolerate the
failure of a VTL node while maintaining
access to all the data within the repository.

To provide the necessary levels of high
availability, enterprise SCO VTL solutions
also need to be able to ride through single
disk failures. The TS7650G supports
heterogeneous storage on the back end, and
IBM recommends the use of RAID
capabilities supported by this back end disk
to provide high data availability. If higher
levels of resiliency are desired, users can
flexibly configure storage subsystems with
the required levels of resiliency. IBM’s Best

Practices provide tools that recommend
certain RAID configurations for it’s
repository (metadata and user data) for
optimal performance and resiliency.

Reliability. Two basic issues were
identified earlier in this area: the risk of false
positives and the verification of retrieved
data. HyperFactor uses a unique approach
to identify and confirm redundant elements.
At a high level, HyperFactor does a very low
latency “fly by” looking for elements that look
similar to what it has already seen. A more
in-depth analysis is then performed only on
the elements identified as “similar” whereas
the “new” elements go immediately into the
index before they are stored on the back end
storage. Competitive approaches execute
their full “chunk evaluation algorithm” on
each and every element, which in the end
generally means they end up doing a lot more
work (at very high latency cost since a large
percentage of references may require reads
from disk) for every element. HyperFactor’s
approach not only handles higher
throughput but also more reliably identifies
each element.

ProtecTIER retains metadata about each
element, one piece of which is a cyclic
redundancy check (CRC or checksum). On
reads, ProtecTIER assembles the required
elements, performing checksums on each
element once they have been converted back
into their original form to verify that the data
element read out of the repository is the
exact same data element originally stored
there.

The RAID capabilities of the underlying
storage subsystems provide yet another level

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P R O D U C T P R O F I L E

of data reliability. Most RAID technologies
from major storage suppliers offer options to
repair bit error rates on the fly if they occur,
and will reliably retain data even as disks
occasionally fail. ProtecTIER solutions take
on this additional level of data reliability as
they support these storage subsystems.

Solution maturity. The ProtecTIER
technology has an installed base of
production deployments that numbers in the
hundreds, most all of whom are in the
Fortune 1000. Representative industries
include financial services, healthcare,
telecommunications, oil & gas, retail, media
and entertainment, manufacturing, and
government. There are customers managing
storage capacities in the hundreds of
terabytes of usable capacity across multiple
ProtecTIER gateways. In its third year of
availability, the base HyperFactor technology
is mature and proven, with most customers
seeing data reduction ratios between 10:1
and 25:1 for backup data.

The IBM acquisition is an important
milestone in ProtecTIER’s technology life
cycle since its target customers care deeply
about issues like reliable long-term
technology sources, keeping the number of
vendor relationships low, worldwide support
coverage, and integration with other key data
protection technologies. IBM is a company
that large enterprises trust to address these
issues.

NOTICE: The information and product recommendations made by the TANEJA GROUP are based upon public information and sources
and may also include personal opinions both of the TANEJA GROUP and others, all of which we believe to be accurate and reliable.
However, as market conditions change and not within our control, the information and recommendations are made without warranty of
any kind. All product names used and mentioned herein are the trademarks of their respective owners. The TANEJA GROUP, Inc.
assumes no responsibility or liability for any damages whatsoever (including incidental, consequential or otherwise), caused by your use
of, or reliance upon, the information and recommendations presented herein, nor for any inadvertent errors which may appear in this
document.

Taneja Group Opinion

Given the amount of data with which large
enterprises have to deal, and the expected
growth rates for this data over the next five
years, non-SCO VTLs are generally not going
to provide a sufficiently scalable, cost­effective solution as a backup target. For this
reason, we see the VTL market rapidly
transitioning to SCO VTLs over the next 1-2
years. How a SCO VTL compares in its
overall performance and scalability are the
two critical issues which set enterprise-class
solutions apart.

With this new announcement, the TS7650G
offers the features required in an enterprise­class SCO VTL: industry leading in-line,
single system throughput, expandability to
multiple petabytes of usable capacity, high
availability with a clustering approach that
supports a global repository, built-in features
to ensure that data is reliably identified,
stored, and retrieved, and a mature solution
that has been reliably deployed in hundreds
of customers across multiple verticals. If
you’re looking for a SCO VTL solution to
handle the kinds of backup workloads
common in large enterprises, IBM’s pedigree
in this area is solid. Just ask their
ProtecTIER customers.

.

Copyright The TANEJA Group, Inc. 2008. All Rights Reserved

87 Elm Street, Suite 900 Hopkinton, MA 01748 Tel: [phone] Fax: [phone] www.tanejagroup.com

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