Simplifying the Network with 10 Gigabit Ethernet Unified Networking

White Paper: Simplifying the Network with 10 Gigabit Ethernet Unified Networking
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Ethernet Enhancements for Storage
Data Center Bridging for Lossless Ethernet
To strengthen 10GbE as a unified data center fabric, the IEEE
has standardized on Ethernet enhancements to support
storage traffic, including FCoE and iSCSI. These extensions,
known collectively as Data Center Bridging (DCB), enable
better traffic prioritization over a single interface, as well
as advanced means for shaping traffic on the network to
decrease congestion. In short, DCB delivers a lossless
Ethernet fabric for storage traffic.
Fibre Channel over Ethernet (FCoE):
Enabling End-to-End Unified I/O
Fibre Channel over Ethernet (FCoE) is a logical extension
of Ethernet that uses Fibre Channel’s Network, Service, and
Protocol layers to carry data packets over Ethernet’s physical
and data link layers. Fibre Channel’s unique network-centric
management model has proven administrative capacities
to scale to thousands of end nodes in a data center. Using
Fibre Channel’s upper layers smoothes the transition to FCoE
because existing SAN-based applications do not need to
change to benefit from the performance and cost benefits of
FCoE. The provisioning responsibilities, now split between
the server and storage administrators, can be maintained
in the transition from Fibre Channel SANs to Ethernet-
based FCoE-powered SANs.
Many Enterprises have extensive FC installations, and the
availability of software-based FCoE initiators makes the FC
SAN easily accessible for any server with a 10GbE Ethernet port.
By allowing FC to use DCB-capable Ethernet, FCoE eliminates
the need for dedicated Fibre Channel host bus adapters (HBAs),
reducing cabling and switch-port requirements, while coexisting
with existing Fibre Channel infrastructures. The result is a simpli-
fied data center infrastructure, lower equipment and power costs,
and universal SAN connectivity across the data center over the
trusted Ethernet fabric.
Introducing the Open FCoE Architecture
The Open FCoE approach consists of standard 10 GbE adapt-
ers and native operating system-based FCoE initiators, which
together provide a robust, scalable, and high-performance
server connectivity option without expensive, proprietary
hardware. As shown in Figure 2, Open FCoE implements
the complete FC protocol in the operating system kernel. It
provides libraries for different system-level implementations,
allowing vendors to implement data plane functions of the
FCoE stack in hardware to deliver optimum performance.
Open FCoE: Momentum in the Linux* Community
The Open FCoE project was accepted by the Linux community in
November 2007 with the goal of accelerating development of a
native FCoE initiator in the Linux kernel. The industry responded
enthusiastically, and today there are over 190 active participants
in the community who are contributing code, providing
review comments, and testing the Open FCoE stack. To date,
the Open-FCoE source web site (www.Open-FCoE.org) has
received over 20,000 hits. Open industry standards and Open
Source play a significant role in the modern data center, as they
lower R&D investment and enable access to a multi-vendor
supply chain that is designed for heterogeneous interoperability,
ultimately resulting in greater choice and lower equipment costs.
The Open FCoE approach offers a number of advantages in
terms of accessibility and ease of use.
Accessibility: The Open FCoE approach makes FC SAN
access available to any server with a DCB-capable 10GbE
adapter installed. IT departments can standardize on these
adapters to simplify server connectivity across multiple use
cases. With FCoE support integrated into the operating
system, FC SAN access will become readily available across
these converged networks and even more accessible once
10GbE LOM technology grows to pervasive status.
Ease of use: Because the Open FCoE approach uses DCB-
capable 10GbE adapters that comply with broad, well-known
Ethernet standards, IT can leverage existing knowledge to
configure and manage these adapters for FCoE deployments.
In fact, IT can standardize on a single product or product family
for all LAN and SAN connectivity. FCoE initiator integration into
the OS also means common OS-based tool support across a
product family or even adapters from multiple vendors, as they
become available.
Figure 4. Overview of the Open FCoE initiator solutions
FCoE data path offloads
Ethernet MAC
Ethernet PHY
Open FCoE Solution
Device Driver
Operating System
Application I/O
SCSI storage interface
Fibre Channel protocol
FCoE transport protocol