Q: What is data center bridging (DCB) and what Ethernet extensions were created to support it?

A: Data center bridging (DCB) is today's buzzword to describe the convergence of Fibre Channel storage atop traditional Ethernet-based devices. DCB specifically refers to four extensions to the Ethernet protocol that enable it to operate with the lossless nature of Fibre Channel traffic. Those four extensions are:

  • Priority-based Flow Control (802.1Qbb), which enables the management of a single, bursty source on a multiprotocol link.
  • Enhanced Transmission Selection (802.1Qaz), which enables bandwidth management between traffic types on multiprotocol links.
  • Congestion Notification (802.1Qau), which addresses the problem of sustained network congestion by moving corrective actions to the network edge.
  • Data Center Bridging Exchange Protocol (DCBX), which allows the automatic exchange of Ethernet parameters between switches and endpoints.
Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.