Riverbed to Encroach on EMC’s Space

Storage makers like EMC who have experienced enviable sales growth for more than a decade may soon find growth slowing for an unexpected reason—Riverbed is about to re-purpose an acceleration technology that has served them well to reduce network traffic, to now take a load off storage servers. How will they do this? They are developing a new box that applies dictionary compression (which they call de-duplication) to permanently reduce the amount of storage space used. The new box, aptly named Atlas, will lift a burden from the server. Here's how it works.

Riverbed's dictionary compression is, in essence, caching on an arbitrary data segment size. The Riverbed Atlas boxes will sit in front of the server watching bytes go by and determine if a chunk of data referred to as a segment can be tagged. The segments have no relationship to a file or file name. Some, few, or many segments can equal a file, and some, few, or many files can equal a segment.

The first time data comes through the Atlas, it detects patterns (segments) in the data, and each segment is tagged with a reference number. The Atlas then saves the segment and reference number in the storage system. It leverages all of the storage features that already exist like RAID redundancy and does not replace the file structure. Files are still found and retrieved by the storage system—they just use fewer storage system resources. Every write and read into the storage system goes through the Atlas box since it knows how to reconstruct the file from the tags and stored file segments.

The power of the approach comes from finding many common file segments across multiple files. Riverbed reckons they can lower the cost of future storage growth (file data) by 30 to 90 percent. Given that the cumulative sum of data storage in the world is predicted to grow exponentially in the next three years, there's no need to feel sorry for EMC just yet. But just as installing Steelhead devices forestalls bandwidth upgrades, installing Riverbed's Atlas devices should forestall storage upgrades, many of which would otherwise be lucrative forklift upgrades. EMC should not get complacent.

• Network Management
• Riverbed
• Storage Management
• storage-area network