Why 16Gb Fibre Channel?

The decision to upgrade an existing SAN (storage area network) infrastructure involves a variety of factors, some related to business processes and others related to technology choices. Customers need to evaluate whether everything is working adequately and whether the SAN requires changes to any of its components, including servers, switches, storage systems and applications. If the SAN infrastructure is handling current workloads efficiently and is expected to adequately support anticipated growth, then an infrastructure upgrade is not needed in the near term. However, if business and data are growing at a rapid pace, or if network and application performance is becoming an issue, a change is probably warranted before performance degradation occurs.


Data center and technology drivers such as multicore processors, high-density servers, increased performance in server I/O, SSD storage arrays and server virtualization are driving the need for increased performance and bandwidth. 16GFC delivers the following benefits that support these technology trends.          


      • Doubled Throughput, Higher IOPS - 16GFC delivers 3200 MByte/sec bi-directional throughput (double 8GFC’s 1600 MByte/sec) and more than one million IOPS adequately supportingdeployments of densely virtualized servers, increased scalability and matching the performance of multi-core processors and SSD based storage infrastructure





      • Backward Compatibility - 16GFC is backward compatible with 8G/4G/2GFC and will auto-negotiate down to the fastest speed supported by both ports. This allows 16GFC devices and switches to be seamlessly integrated into expansion segments of existing FC networks without a forklift upgrade. In addition, existing 8G/4G/2GFC OM1-OM4 optic cabling infrastructure can carry 16GFC traffic.
      • Reduced Capital Expenses (CAPEX) - Higher speed 16GFC reduces the number of expensive HBAs and switch ports required to achieve similar performance, resulting in lower front end CAPEX. Fewer links also mean less structured cabling investment, running at hundreds of dollars per port.
      • Reduced Operating Expenses (OPEX) - Installing two 8GFC HBAs for doubling bandwidth could result in 100 percent increase in power consumption while installing a single 16FC HBA could deliver the same result for approximately a 40 percent increase in power. Reduced port counts also simplify manageability.
      • Investment Protection Roadmap - Mission critical applications have long relied on a dedicated FC network to deliver the required performance, resiliency and serviceability. Deploying 16GFC not only preserves this architecture, but is also future-proofed.  Standardization of 32GFC is in process, ensuring the continuity of FC technology.


Mike McNamara


I believe, 16 Gb FC is only backwards compatible to 8/4.

You'll need 8 Gb SFPs to be backwards compatible to 2 Gb FC.


All FC solutions will only support 2 previous generations link speed. 4 supports 2/1, 8 supports 4/2, 16 supports 8/4. Even with 8GFC SFP's you won't be able to use 2GFC connectivity.

The speed limitations are based on the SFP's, not ASIC/Switch.  You can put an 8Gb SFP into the new 16Gb switches to support a 2Gb device.  4Gb SFP's are not supported, so there is no support for 1Gb devices (and condolences if you still have to support a 1Gb device!) 

Thanks for the clarification on 16Gb FC compatibility, now just need to find some 16Gb SFPs! Avago have one listed, but no pricing/availability online. Any suggestions?

Dave Barnard

cinedigital, London