Introduction

Storage Bridge Bay, or SBB, is an open standard for storage disk array and computer manufacturers to create controllers and chassis that use multi-vendor interchangeable components. The SBB working group was formed in 2006 by Dell, EMC, LSI and Intel and the standards are openly published at the SBB website. Visit their web site to learn more about the background and current member companies.

SBB based solutions have been shipping for some time now but have not really been marketed to end users for their multi-vendor capabilities. The primary benefits so far are based around either reduction in test and development costs for the vendors themselves or from a tier 1 OEM perspective (i.e. the IBM, Dell or HPs of the world), it provides the ability to maintain a standard chassis (which includes the drives, disk trays, internal mid-plane that connects the drives to the controllers) and invite several vendors to bid for the controller portion. All in all, this is a solid attempt to replicate the PC whitebox model by standardizing the various components inside of a RAID disk array product and enabling multiple different vendors to make plug and play components.

Primary Features of SBB

The SBB specification amongst other things, standardizes on the interchangeability of the primary pluggable components or FRUs – field replaceable units i.e. the controller and power supplies. It does not however dictate disk drive tray styles, overall chassis size or rack mounting features allowing vendors to continue to differentiate look and feel.

In summary, the v2.0 standard addresses:

  • Controller formfactor, internal connections from controller to drives and power supply component to facilitate mix and match controllers from different vendors in the same chassis
  • Controller hookup connections for up to 48 drives (3Gbps), power supplies and dual controller interconnects
  • Power requirements of up to 200W per cannister
  • Minimum management requirements that the controllers must perform to conform to the standard

It does not however dictate which host interfaces, drives or other auxiliary connections are required on the controllers themselves – this is up to the individual vendors to specify.

End User Benefits

Long term, end users stand to benefit from SBB as it accomplishes two things: firstly greater competitiveness in what has been a closed, proprietary market for many years, and secondly the introduction of more feature rich controllers based on alternative architectures.

Both Intel and AMD have provided SBB reference designs to the developer community which provide what is essentially an x86 class server in an SBB formfactor. While this is generally a more expensive solution that that provided by established vendors such as LSI Logic, Infortrend or DotHill for example, they do provide a greater flexibility for open storage vendors to add value add functions beyond the basic RAID level and traditional disk array management functions such as snapshot or replication such as integrated storage virtualization functions or unified (SAN and NAS) functionality relatively easily.