Driving data center network convergence with Fibre Channel over Ethernet technology

By Jason Phippen, Director Marketing, and Chris Hill, Major Account Manager, both of Emulex Ltd.

The Need for Network Convergence

Since the emergence of Fibre Channel-based Storage Area Networks (SANs) in the late 1990s, enterprise IT managers have maintained two types of networks: a SAN for storage I/O traffic and a Local Area Network (LAN) for data networking traffic. The increasing adoption of blade server and server virtualization technologies has extended the demand for SANs from the traditional database tier to the application server and Web server tiers. While IT managers could continue to operate with a dual-network model across the enterprise, the overarching need for data center consolidation is forcing organizations to seek network convergence solutions that will improve the overall cost structure and operational efficiency of the data center networks.

Leveraging Ethernet for Network Convergence

Ethernet is the predominant networking technology in the data center. The prevalence of Ethernet makes it an ideal choice to produce the convergence of data center networks. However, Ethernet, as it exists today, is prone to high latencies and packet loss when subjected to network congestion – characteristics that are highly unsuitable for carrying storage traffic. IEEE is working on enhancements to Ethernet protocol, rightfully termed “Enhanced Ethernet (EE),” to eliminate these drawbacks and facilitate storage and networking traffic to be carried over the Ethernet infrastructure.

Key enhanced abilities being rolled into the emerging 10Gb/s Ethernet include:
•    Isolation and prioritization of different traffic types using Priority Flow Control
•    Bandwidth guarantees for multiple traffic types
•    Communication between end-points and switches through an enhanced management protocol

Emergence of FCoE and 10Gb/s Converged Network Adapters

In order to leverage the Ethernet enhancements and drive convergence in the data center networks, a consortium of storage and data networking vendors have worked together under the guidance of the INCITS T11 committee to develop a new standard called Fibre Channel over Ethernet (FCoE). FCoE encapsulates complete Fibre Channel frames onto Ethernet frames, enabling a consolidated 10Gb/s Ethernet infrastructure to carry both data networking and storage networking traffic. By continuing to use Fibre Channel as the upper layer protocol, FCoE also provides seamless connectivity to existing Fibre Channel SAN resources.

A new family of adapters called Converged Network Adapters (CNAs) leverages the Ethernet enhancements and FCoE to drive convergence over the underlying 10Gb/s EE infrastructure. The FCoE CNA offloads Fibre Channel protocol processing from the CPU and provides high-performance storage connectivity while improving overall CPU utilization.

Benefits of FCoE-enabled Network Convergence

An FCoE-enabled converged network provides the following important benefits to IT organizations:
• Lower total cost of ownership through infrastructure simplification
A converged network based on FCoE lowers the number of cables, switch ports and adapters required to maintain both SAN and LAN connectivity. The reduction in the number of adapters facilitates the use of smaller servers and the expanded offload to the CNA enables higher CPU efficiency, which directly affects power and cooling costs.
• Investment protection for existing SAN infrastructure
FCoE retains Fibre Channel as the upper layer protocol, which enables seamless connectivity to existing Fibre Channel SAN infrastructure. The Fibre Channel frame encapsulation methodology is less compute-intensive and thus ensures high levels of storage networking connectivity to existing SANs without the need for routers. The continued use of Fibre Channel as the storage protocol also ensures that existing investments in management tools and processes are protected, further lowering the long-term operating cost of the data center.
• Increased IT efficiency and business agility
A converged network streamlines and eliminates repeated administrative tasks such as server and network provisioning with a “wire once” deployment model. The converged network also improves business agility, allowing data centers to dynamically and rapidly respond to requests for new or expanded services, new servers and new configurations. The converged network fully complements server virtualization in addressing the on-demand requirements of the next-generation data center, where applications and the infrastructure can now be provisioned on the fly.
• Maintained alignment with existing operational models and administrative domains
FCoE allows organizations to roll out network convergence over multiple stages. The technology drives consolidation in new deployments without affecting the existing server and storage infrastructure or the processes required to manage and support existing applications. The technology enables IT architects to design a data center that aligns with existing organizational structure and operational models. This minimizes the need to unify or significantly overhaul operational procedures used by storage and networking IT staff.

Deployment Architecture

As data centers transition to 10Gb/s Ethernet to meet the demands of blade servers and server virtualization environments, it is imperative that IT managers also plan for network convergence with FCoE. The CNAs when combined with 10Gb/s Ethernet Switches (with FCoE support) provide the ideal solution for converging the server access network.

Emulex’s Role in Network Convergence

Emulex is one of the leading proponents and developers of FCoE technology. Emulex LP21000 CNAs are designed to support high-performance storage and networking applications in enterprise data centers. The Emulex CNAs fully leverage the proven Emulex LightPulse® architecture. The use of a common driver model ensures the same driver code is used for Emulex FCoE CNAs and Fibre Channel host bus adapters (HBAs) thus extending their reliability, performance and manageability.

Emulex has closely partnered with Cisco in developing an FCoE-enabled converged network solution for enterprise data centers. The combination of the Cisco Nexus 5000 switch and the Emulex LP21000 family of CNAs provides standards-compliant, fully interoperable solutions that facilitate faster adoption of FCoE-enabled convergence in the data center. To help customers evaluate and fully understand the benefits of network convergence, Emulex CNAs are also made available at no cost for 90-day trials with select Cisco Nexus switches.

Conclusion

Enterprise IT managers are constantly facing challenges of enhancing the availability and operational efficiency of the data center. FCoE-enabled network convergence provides an evolutionary approach toward achieving high operational efficiencies within the network infrastructure. Besides simplifying network infrastructure, FCoE protects existing investments in Fibre Channel SAN and SAN management tools and processes. Enterprises are now well-positioned to begin deploying the technology in a phased approach, so as to streamline the process for mass adoption. In addition to lowering the total cost of network infrastructure, FCoE-enabled network convergence empowers organizations to be more adaptive in meeting their dynamic IT requirements.

For more information visit www.emulex.com/products/fcoe or contact Chris Hill (chris.hill@emulex.com)