Cloud storage as a service is available today, but how can you realize the cost savings it promises? Learn what use cases and what capacities can make cloud storage work for your business with substantial cost savings over in-house solutions. Based on the results of this analysis, cloud storage can be very compelling for companies replicating up to 60 TB to a public cloud. For a mid-sized company or departments within a larger organization, this represents a substantial capacity range for replicating data to the cloud.

1. Economics of Public Cloud
Storage:
For primary storage and
disaster sites
November 2009

2. Comparison
 Compare total cost of ownership (TCO) of cloud storage versus local
storage
 Capital and Operating expenses, ignoring local site floor/power/cooling costs
 Calculate 3-yr TCO across the following storage use cases
 Primary storage tier
 Local storage array, local tape backup –versus-
 CloudArray™ storage gateway, cloud storage, snapshot-based backup
 Offsite replicated storage tier for disaster recovery
 Local storage array with remote replicated disaster site –versus-
 Local storage array with CloudArray™ cloud-hosted disaster site
 Observe TCO as capacity increases
 Start with 1TB baseline
 Compare across fixed size X TB storage configurations
 Compare across linearly growing 0-X TB storage configurations
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3. Baseline: 1TB storage capacity
$250,000.00
$200,000.00
$150,000.00
Capex
$100,000.00
Opex
3yr TCO
$50,000.00
$0.00
Local Cloud In-house Cloud
Storage Storage Disaster Disaster
recovery recovery
Primary storage tier Offsite replicated storage tier
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4. 3-yr TCO:
Fixed capacity, primary storage
$120,000.00
$100,000.00
$80,000.00
$60,000.00 Local Storage
Cloud storage
$40,000.00
$20,000.00
$0.00
1 2 3 4 5 6 7 8 9 10
Capacity in TB
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5. 3-yr TCO:
Fixed capacity, offsite storage
$400,000.00
$350,000.00
$300,000.00
$250,000.00
In-house Disaster
$200,000.00 recovery
$150,000.00 Cloud Disaster
recovery
$100,000.00
$50,000.00
$0.00
1 2 3 4 5 6 7 8 9 10 15 20 25
Capacity in TB
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6. 3-yr TCO:
Growing capacity, primary storage
$160,000.00
$140,000.00
$120,000.00
$100,000.00
$80,000.00 Local Storage
Spikes in cost
$60,000.00 are from Cloud storage
additional
storage array
$40,000.00
$20,000.00
$0.00
1 5 10 15 20 25
Capacity inTB
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7. 3-yr TCO:
Growing capacity, offsite storage
$700,000.00
$600,000.00
$500,000.00
$400,000.00 In-house Disaster
Spikes in cost recovery
$300,000.00 are from
Cloud Disaster
additional
storage array recovery
$200,000.00
$100,000.00
$0.00
1 5 10 15 20 25 30 35 40 45 50 55 60 65 70
Capacity inTB
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8. Results
 Small capacities (~1TB)
 Cloud storage appears considerably less expensive than local
 Storage arrays do not scale down to a true pay-as-you-go model
 For fixed storage capacities
 Cloud storage less expensive up to about 7TB for primary storage and 20TB for
offsite storage
 Cloud saves significantly on the remote site infrastructure needed for an offsite
copy of data
 Linearly growing storage capacities
 Crossover point advances to 20TB for primary storage and 60TB for offsite
storage
 Cloud benefits from a pay as you go, 100% utilized model, versus a pay up front,
underutilized model.
 All results based on model assumptions and may vary across
configurations
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9. Model Cost Assumptions
Local Storage
Local storage array $30,000.00
Local tape library $3,400.00
Local storage base capex $33,400.00
# of drives per RAID set 5
cost per drive $875.00
capacity per drive (GB) 600
RAID set capacity(TB) 2.40
RAID set cost $4,375.00
RAID opex (annual) $5,000.00 (maintenance and administrative cost)
Backup opex (annual) $5,023.05 (maintenance and administrative cost)
Storage array capacity (TB) 45.60
Local power/cooling/floor space not factored for this study
Cloud Storage Cloud Provider Cost 0-50TB 50-100TB
Cloudarray base license $4,000.00 max cap TB 25 capacity cost per GB/mo $0.15 $0.14
Capacity cost per TB/mo $150.00 $140.00 bandwidth cost per GB/mo $0.10 $0.10
Bandwidth cost per TB/mo $100.00 (assuming 100% update rate/mo)
Additional capacity for snapshots 10.00%
3yr capacity total cost per TB $9,900.00 $9,504.00
Cloud opex base 1,000.00
In-house DR to remote site
In-house DR base capex $107,400.00 (2X storage array, $20K remote lab infrastructure + $25K replication license)
RAID set cost $8,750.00 (2X capacity)
Remote site annual operating costs $24,114.00 (space, power, cooling, multi-site management, network)
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10. Additional resources
 Clarity AP used to model baseline configuration
 Free download from www.twinstrata.com
 Download configuration file from Clarity AP portal: cloudROI - local.cyr
 Change parameters to model your exact configuration
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11. Thank You
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