Loss-less Ethernet via Data Center Bridging
FCoE requirement: Loss-less Ethernet via data center bridging To deliver storage traffic reliably and in a timely manner, Fibre Channel protocols assume that the underlying fabric is loss-less, even during network congestion. FCoE can use existing 10 Gigabit Ethernet interconnects via the existing IEEE physical pause mechanism.During periods of heavy congestion, customers can pause lower-priority traffic while allowing high-priority and latency-sensitive tasks (such as data storage) to continue.
But new Ethernet extensions, such as priority flow control under the label DCB (Data Center Bridging)-also known as Data Center Ethernet or Converged Enhanced Ethernet-enable logical pause capabilities in order to prioritize traffic types when consolidating I/O. This allows the creation of virtual lanes within an Ethernet link, with each virtual lane assigned a priority level.