"> Nexsan steps up to the plate
Nexsan steps up to the Centera challenge
May 29, 2007: 5 years after the first content addressable storage (CAS) solution arrived, Nexsan is tackling digital archiving with its security-focussed new CAS range, Assureon. Liam Tung takes a tour of the Assureon with Nexsan’s Australian distributor, Busi-soft’s George Poutakidis.
Taking on EMC’s Centera is no small task. It is synonymous with disk-based archiving and was the first to offer CAS. Its installed user is large; its customers have recognisable brands. At the same time, what customers want from a long term, disk-based archiving solution has changed over the past 5 years. According to Busi-soft’s MD, George Poutakidis Nexsan’s Assureon line - a second generation CAS solution – reflect these changes in demand and make it a formidable competitor to Centera.
The Nexsan Assureon comes in three options: Assureon SA Appliance (for SMBs and Departmental applications); Assureon NX Appliance (for the long-term storage of business-critical information); and Assureon System (secure high availability archive solutions for larger applications). The difference with Assureon, according to Poutakidis, is its scalability, security and improvements to MD5 hashing.
Rather than Centera’s "brick" mode scaling, Assureon’s processing power scales independently of storage. Its storage units SataBeast, SataBoy and SataBlade offer native capacities of 31.5 TB, 10.5 TB and 6 TB respectively.
The Assureon line addresses concerns over the MD5 hashing algorithms used in Centera to generate unique addresses for new content by using a combination of MD5, SHA-1 and the file length to generate. Poutakidis says, “Unlike MD5 alone, as used by Centera, this 288-bit process eliminates the possibility of a duplicate CAS address and consequential data collision.”
Over the last few years the security of information-at-rest has become a major issue for organisations. California’s 1386 Bill, introduced in the same year as Sarbanes-Oxley, was a major catalyst for this, and suggested a convergence between security and storage. The cost of disclosing data breaches altered the value encryption could deliver.
Nexsan acknowledged the need for secured storage and offers hardware-based 256-bit encryption with a multiple-site key management process including remote manifest deposit. Every 5 minutes Assureon sends a “manifest” to the remote key server. (The "manifest" is a list of all files including: serial number, unique file identifier, date and time stamp, the file's retention policy, and the serial number of the encryption key used to encrypt the recently stored file. The key server is hosted by a trusted third party and each manifest is stored back into Assureon which becomes the first entry in the subsequent manifest.) The advantage of this process is that users can prove the authenticity and completeness of all records by comparing the local copy of the manifest against that stored at the remote key server. By sending the manifest to the key server, the key server can associate encryption key serial numbers to file serial numbers for its records.
Poutakidis says it encrypts at the individual file level and will also encrypt metadata and the encryption keys themselves. “At the end of a retention period Assureon performs a military strength disposition process to delete the specific files on all types of media including offline. Centera offers no such encryption and subsequent data privacy protection.”
“And lastly, Assureon has a lower price point and most importantly there no ongoing licensing fees,” says Poutakidis.
To give some idea of that price, Poutakidis says the Assureon NX 5U Appliance NAS Interface with 3.75TB usable storage comes in at $69,452, while the Assureon SA 7U Appliance with 2TB Usable Storage is $89,214. Assureon SX-10 4TB is $49,715.00 which is also available in a base Unit with 7TB or 21TB. The Assureon GX2-10 7TB is $86,435.00, also available in a base Unit with 14TB or 21TB. And at the big end, Assureon GX4-21 7TB comes in at $109,055.00, which is also available in a base unit with 14TB, 21TB, 42TB (2 x 21), 63TB (3 x 21) or 84TB (4 x 21).
The smarts: compliance and records management
To show the management features of Assureon’s GUI Web-interface, Assureon Explore Poutakidis and Busi-soft’s systems integrator, Byron Chen, took IDM on a virtual tour of Assureon’s smarts. Instead of using APIs it uses a client-based agent that automates policy assignment and management along with data movement.
The Assureon allows retention policies to be set and managed on a scheduled or real-time basis from authorised PCs on the network. Access to folders on the archive can be restricted to certain users or groups. Since it uses Windows Active Directory there is no need to replicate group-based policies once inside.
The FSW Watch feature enables users to review which policies apply to different file locations, helping the user in planning archive strategies. Archiving policies can be set and saved according to the needs of different business units or functions.
If certain groups of files are not required to be retained, the “Enable Flexible Retention” box can be checked. When determining asset retention, users can choose whether to archive the file while leaving the original in place, archive and delete the original, or archive and replace the original with a shortcut. Policy can also be set for instances where a file hasn’t been changed in a pre-determined period, say 90 days, which helps reduce the load on servers.
Poutakidis says some customers have found the ability to do file-specific archiving by extension, filename or directory useful to control automation at a more granular level. Depending on work processes, one variable may distinguish reusable content from others that leave the process.
The file disposition functionality in Explore allow for a final check of files prior to destruction. By bringing up the list of “candidates”, you’re given a last chance to remove a file from the candidate list. Disposition can also be scheduled for less active times in the day to minimise disruption.
A major bonus to storage efficiency is Assureon’s Single Instance Referencing (SIR). Explore allows approved users to restore files at the user level while SIR ensures there’s only one copy is stored where duplicates exist. If there are 10 identical files, only one will be kept.