When is a node not a node?
One of the things that irks me is when press/analysts/vendors compare a competitor’s solution to a one node SEPATON solution. SEPATON’s VTL as well as our DeltaStor deduplication and DeltaRemote replication products rely on our DeltaScale™ architecture which is designed around the concept of grid scalability. The grid allows us to scale dynamically and transparently across multiple independent nodes. This is very different from competing solutions that rely on a monolithic server approach.
Creating a truly dynamic and grid-based VTL with deduplication and replication is difficult. That’s why most vendors have opted for a single node approach. In order to achieve performance, they include the largest servers feasible to try to minimize the server hardware bottleneck. These are typically 2U+ servers that are loaded with huge amounts of RAM, four or more of the fastest possible CPUs and often SSD’s to hold the deduplication index. The challenge with this approach is that the customer must buy the right long-term solution to meet their needs on day one. If they do not, they will either have to perform a forklift upgrade to a new product version with a faster server or purchase multiple iterations of the same system—and cobble them together.
SEPATON’s DeltaScale architecture relies on a grid of relatively inexpensive 1U nodes. All of these nodes appear as one system image and share common back end storage, virtual libraries/drives and a deduplication repository. The benefit of this approach is that a customer is not forced to buy the maximum performance required on day one. Instead,they can buy what they need today and increase performance later by adding nodes to the grid. The system automatically recognizes the increased performance and integrates it, load balancing all processing across all nodes without operator intervention. This also helps with the economics of the system since SEPATON’s nodes are less expensive than those of the competition. SEPATON could easily inflate single-node performance by providing similarly powerful nodes as the competition does, but we believe that the benefit of low cost and granular performance in our current design is a better fit with our customers’ needs.
As a further clarification, I thought that it would be helpful to give an idea of the cost differential between a SEPATON node and a monolithic one from a competitor. In this case, I assume a node such as that recently announced by Data Domain. I configured systems on Dell’s website and the price stated is based on estimated configurations, and excludes any custom parts or volume discounts. The point is to illustrate the order of magnitude difference. Click on the price to view a PDF of the server quote from Dell.
SEPATON Node | Competitor Node | |
Dell list price |
The result is that a SEPATON node is about one quarter the price of those used in competing systems.
In summary, SEPATON’s DeltaScale architecture supports a grid of thin nodes while competing solutions typically rely on one over sized node. The SEPATON approach provides the ability to scale performance dynamically in a single system image through the addition of nodes and the alternative is to increase performance by adding independent systems.
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30. Jul, 2009 







Not sure if its fair to say the SEPATON is a truly grid architecture as a single node going down can bring the entire grid down. It provides grid scalability and addressability but not necessarily grid availability. Fair enough?
I also think it is worth mentioning the cost of a single node whether is be SEPATON, Data Domain, or any other VTL vendor is not strictly the cost of hardware, but the cost of hardware+software+support+things like RU space/power/etc. Might be worth providing a comparison looking at all those components.
Cheers.