SONETizing storage

If you are looking to connect multiple storage-area networks over long distances, then utilizing technology known as storage over SONET may be something to look at.

Basically, the idea behind storage over SONET is to physically extend the full integrity of the SAN fabric over long distances, allowing users to link geographically dispersed SANs into one system. It also lets users more effectively control bandwidth.

According to our Technology Update author (sadolph@akara.com) most enterprise storage applications require less than full protocol throughput capacity. For example, a Fibre Channel link may provide 100 megabytes of capacity, the application typically requires much less than that.  Dense wave division multiplexing-only products, which can provide approximately 250M bit/sec of real bandwidth per wavelength, typically assign an entire wavelength to each Fibre Channel, regardless of throughput requirements, our author states. This results in a low typical efficiency of 4% to 12%. A storage over SONET device can subdivide a wavelength amongst multiple storage links, and dedicate the exact amount of bandwidth required for each application to each link, our author says.

Storage over SONET promises to improve the performance of applications such as remote disk mirroring, disaster recovery and remote back-office applications such as those from Oracle.https://www.nwfusion.com/tech/2003/0331techupdate.html

For more on storage over SONET see: