How Fibre Channel over Ethernet Improves Data Center Efficiency

By Jay Kidd  |  Posted 2008-11-24

How Fibre Channel over Ethernet Improves Data Center Efficiency

Fibre Channel over Ethernet transports Fibre Channel frames over an Ethernet fabric. This enables data centers to increase application performance while simultaneously reducing cost, power and manageability tasks by converging storage, networking and clustering data on a single fabric.

There are six key benefits of FCoE:

Benefit No. 1: High-performance storage access over loss-less 10 Gigabit Ethernet fabrics

Benefit No. 2: Transparent access to storage devices using existing SAN (storage area network) management methods

Benefit No. 3: Retention of enterprise-proven Fibre Channel drivers and management tools

Benefit No. 4: Lower capital, energy and cooling costs with fewer adapters, cables and switches

Benefit No. 5: Lower management overhead by maintaining a single fabric

Benefit No. 6: Increased application availability by simplifying the network and server configuration

FCoE is the encapsulation of Fibre Channel in Ethernet

FCoE is an evolution of Fibre Channel that uses Fibre Channel's network, service and protocol layers to carry data packets over Ethernet's physical and data link layers. Using Fibre Channel's upper layers simplifies FCoE deployment by allowing customers to leverage enterprise-proven Fibre Channel software stacks, management tools and trained administrators. Most importantly, no change is required for mission-critical applications to benefit from the performance and cost benefits of FCoE.

FCoE Deployment in Data Centers

FCoE deployment in data centers

The first FCoE products will be CNAs (Converged Network Adapters) that provide server LAN and SAN connectivity over Ethernet. In addition, FCoE switches will connect FCoE-capable initiators (server side) to existing Fibre Channel SANs, enabling customers to consolidate server interconnectivity on a single Ethernet fabric.


FCoE access switches and CNAs, or server adapters with FCoE initiators, simplify the network topology

To the nodes in the Fibre Channel SAN, the FCoE initiators appear to be directly connected, and can be managed and maintained with the same tools.

A fully converged network architecture with end-to-end FCoE

Next, native FCoE storage arrays, along with existing iSCSI and NAS storage, enable a fully converged fabric.

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.

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.

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.

Benefits of Convergence: Cost and Power Savings

Benefits of convergence: Cost and power savings

Data Center Bridging Ethernet and FCoE make it possible to converge enterprise storage, networking, management and clustering data onto a single fabric that is simple to manage, high-performing and cost-effective.

Significant cost savings can be expected by converging storage and networking onto Ethernet fabrics. Not only are energy, management and maintenance costs reduced, but the cost of Ethernet adapters, cables and switches is lower than Fibre Channel because of the higher volumes and ultracompetitive market forces.

Converging on a single Ethernet network eliminates the need for multiple host I/O cards, including host bus adapters and NIC cards (and separate physical networks for connecting those hosts together). As a result, users can recognize significant savings in power consumption across the data center. In addition, a converged network allows for the reduction of the number of host adapters in each server, and the number of switches and cables required to build a data center infrastructure.

 Jay Kidd is chief marketing officer at NetApp. Jay has extensive experience in storage, networking and high-performance systems. Before joining NetApp, he held the position of chief technology officer and VP of product management at Brocade. Before joining Brocade, Jay was VP of marketing for Omneon Video Networks (a supplier of storage and networking equipment for video broadcasters) and Multigen (a real-time 3-D simulation software company).

Prior to working at Multigen, Jay spent seven years at Silicon Graphics (SGI), where he directed marketing efforts for the graphics workstations, servers and SGI Web systems business. Earlier in his career, Jay worked at Hewlett-Packard, where he held key engineering positions in the Information Networks group.

Jay holds a bachelor's of science degree in electrical engineering from Princeton University. He can be reached at

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