The advent of sever virtualisation, the growth of digital data and the adoption of Web 2.0 applications are driving the need for highly flexible, highly scalable and high-performance data centre architectures. This must be accomplished while maintaining network simplicity for reduced capital and operational costs.
Fibre Channel (FC) networks have long provided organisations with the reliability, performance and network intelligence for low-latency, high-bandwidth applications. However, today, organisations are evaluating the possibility of leveraging a new Converged Enhanced Ethernet (CEE) infrastructure, which gives them the ability to consolidate multiple transport layers on a single physical interconnect.
CEE will enable a new protocol called Fibre Channel over Ethernet (FCoE), which allows organisations to extend the reliability and network services of Fibre Channel to a broader range of server environments. This will reduce costs and complexity for customers implementing a virtualised data centre.
While FCoE is a powerful new technology that will be capable of transforming the way enterprises deploy and manage data centre infrastructure, it is important to note that it is a new technology. It will take time to fully develop standards and implement correctly in a cost-efficient way.
FCoE will aggregate the number of network interface cards (NICs), host bus adapters (HBAs), and cables needed by a server, because multiple protocols will be able to share a single physical transport layer. This will provide the framework in which to deploy a robust, powerful, scalable and simple data centre fabric. Armed with the ability to extend FC benefits to CEE networks, IT departments will be able to support increasingly powerful applications, growing data pools, increased bandwidth and the expansion of holistic virtualised strategies — all with managed growth and cost.
Extending fabric intelligence throughout the data centre
FCoE extends the transportation of the existing FC protocol over a completely new class of transport: CEE. Proponents of CEE aim to provide converged I/O for servers supporting TCP/IP, storage access and high-performance server-to-server connectivity on the same transport layer with the enhanced efficiency, security, low latency and ultra-high-performance demanded by virtual applications. The goal of the new architecture is to create a deterministic, lossless, high-performance protocol while managing growth and cost.
Today’s ethernet networks do not have these fundamental characteristics, making them unsuitable as the basis for a reliable and flexible data centre fabric. On the other hand, FCoE uses the proven, standard Fibre Channel protocol and allows customers to continue to expand their existing Fibre Channel network infrastructure today and leverage FCoE and CEE technology in the future for interconnectivity, avoiding a costly and disruptive rip-and-replace migration strategy.
The FCoE protocol creates a new server edge interconnect that can help reduce the cost of large-scale server deployments while maintaining the advantages of Fibre Channel. Today, some rackmount and blade servers implement a complex set of interface cards to connect to TCP/IP, Infiniband and fibre channel networks. Many organisations deploy multiple interface cards of the same protocol in each server, providing performance, redundancy or network separation. However, this leads to servers with four, eight or even twelve different interface cards and their corresponding cables connecting the server to the various networks. Cabling complexity becomes an issue, since each of the interface cards has at least one cable connecting it to a switch. CEE would allow a single interface card in the server to run multiple protocols over the same physical interface.
Benefits of utilising CEE
The ability to use CEE as the foundation for the data centre architecture provides many cost savings, including capital costs and ongoing operational costs. These include:
- Equipment procurement — fewer interface cards required.
- Cables and cabling costs — consolidation of the number of server interfaces, resulting in fewer cables from the server to embedded or top-of-rack switches. This reduces cable expenditure and management complexity, also mitigating the potential for human error.
- Power and cooling — the consolidated interface cards require less power and cooling.
FCoE migration strategy relies on existing Fibre Channel infrastructure
FCoE is not a replacement for Fibre Channel, which will continue its vital role in the data centre due to its built-in performance, scalability and security. Analyst firm Gartner predicts that “for non-critical and mission-critical applications, converged networks must be engineered to the appropriate level of reliability. In life-critical applications, separate networks probably will be required.”
Instead, FCoE augments existing Fibre Channel fabrics, providing enterprises with additional server connectivity options. Different servers will have different requirements, which will drive the choice of protocol, fabric interface and the overall design of the fabric itself. However, until FCoE is ready for full deployment in production environments, organsiations will rely on Fibre Channel in the data centre.
Until that time, careful work is underway to ensure that Fibre Channel seamlessly interoperates with the server environment, whether it runs over a Fibre Channel physical interface or over a CEE physical interface. This standardisation and consistency will enable organisations to eventually migrate current procedures, policies and best practices to CEE if they so choose.
FCoE in summary
Converged Enhanced Ethernet (CEE) and Fibre Channel over Ethernet (FCoE) are powerful new technologies that organisations can leverage to extend Fibre Channel reliability, network services, intelligence and performance to networks that have traditionally relied on ethernet. As a critical component of the future state-of-the-art data centre architecture, these new protocols will allow organisations to build a reliable, powerful and dynamic infrastructure that enables data centre virtualisation.
*Graham Schultz is Country Manager A/NZ at Brocade.