Analyst reports, press articles and the blogosphere are full of commentary about new fabric architectures from Brocade, Cisco and Juniper, that are designed for flatter scale-out in virtualized clouds, LAN/SAN convergence and 40/100Gbs performance. Brocade was the first to introduce this class of fabric with the unveiling of its Brocade One architecture, VCS technology and VDX switches in June of 2010. Cloud-optimized fabrics built with this class of technology connect virtual servers and their application workloads to other virtual servers, as well as to virtual LUNs in storage resource pools--all while maintaining secure, load-balanced client access to the Web, applications and databases deployed on virtual machines.
Cloud-optimized fabrics consist of a switched fabric and server end nodes, but the industry buzz about new fabrics excludes mention of network adapter innovation. Perhaps it's because the industry has its hands full assimilating infant Converged Network Adapter (CNA) technology. Adoption of 10Gigabit Ethernet CNAs started to ramp up in 2010, mostly because server vendors bundled the technology with their products. However, the vast majority of CNA ports were deployed to provide a fatter 10GbE pipe to virtualized servers. The deployment of CNAs running Fiber Channel over Ethernet for LAN and Fiber Channel SAN convergence has been slow because an investment in new FCoE switching infrastructure is an expensive prerequisite. According to IT Brand Pulse, in 2010, the total available market (TAM) for 10GbEt LOM and adapters grew to $327M, or 17.8% of the total network adapter market opportunity.
The silence surrounding new adapter technology to complement faster, flatter and more virtualization-aware switched fabrics is about to end. IT Brand Pulse expects Brocade Communications--first to introduce the newest class of switched fabric--to be first to introduce a new class of adapter called a Fabric Adapter (FA). FA functionality is a superset of CNA functionality with the following new technology added: simultaneous connectivity to Ethernet (LAN, NAS, iSCSI SAN and FCoE SAN) and Fibre Channel networks, 40Gigabits of adapter bandwidth supporting combinations of 10GbE, 16Gb Fibre Channel ports and dynamic migration of virtual machines from one network protocol to another (for example, FCoE to iSCSI).
Three years ago, when the first generation of CNAs was unveiled, my expectation was that by 2011 the adoption of FCoE would be well on its way. In 2008, I thought integrating Fibre Channel connectivity into a future CNA would burden the adapter with logic and cost that would hardly ever be used. Instead, the majority of IT departments have voted to bypass FCoE and stay with servers connected to dedicated Ethernet and Fibre Channel networks via separate Ethernet CNAs and Fibre Channel HBAs. Given IT's preference for separate Ethernet and Fibre Channel networks, convergence at the server using a Fabric Adapter that can support the existing networks should be immediately attractive to data center managers.
Connecting servers to LANs and Fibre Channel SANs used to involve a NIC for LAN connectivity and a Fibre Channel HBA for Fibre Channel SAN connectivity. Today, 10GbE adapters from all the major adapter vendors are CNAs that can be deployed as a NIC alongside a Fibre Channel adapter or, if FCoE is used, as a converged adapter. Not all major adapter vendors have the Fibre Channel ASIC core and software stack needed to build an FA, so FAs will not completely replace the current generation of CNAs. IT Brand Pulse expects LAN and SAN connectivity to be shared by three types of adapters in the future (Ethernet NICs, Fibre Channel HBAs and Ethernet + Fibre Channel Fabric Adapters), at least until the IT community shakes out a winning technology or two. The vendors capable of delivering FAs are vendors that already have Fibre Channel ASICs and software stacks. As a result, IT Brand Pulse is expecting Brocade, Emulex and QLogic to provide FAs. For the same reason, Broadcom, Intel and Mellanox are not expected to develop Fabric Adapters.
The new capabilities of a Fabric Adapter are made possible by two key technologies.
- ASIC Speaking Ethernet & Fibre Channel The first generation CNAs were dual-ASIC designs with an Ethernet ASIC, a Fibre Channel ASIC and some logic tying them together. Second-generation CNA ASICs were dual core. And now Fabric Adapters have a single ASIC core that can natively speak either protocol. Brocade is the first adapter vendor to integrate its Ethernet and Fibre Channel cores into one. The results are chips that can be used to converge traffic in a Fabric Adapter, or to converge traffic in a storage system. Storage Array vendors should love this technology because it frees space on their array controllers and/or eliminates the need for daughter cards to configure Ethernet or Fibre Channel.
- Virtual Fabric Link (vFL) IT Brand Pulse defines a Virtual Fabric link as a Fabric Adapter configured as a virtual NIC, virtual iSCSI HBA, virtual Fibre Channel HBA or virtual FCoE HBA--depending on the need of the virtual machine and on the application the VM is supporting. vFLs enable adapter consolidation while maintaining management granularity and isolation in virtual environments. The concept of virtual adapters is not new, but this is the first time this concept is taken to native Fibre Channel. vFL implementations will evolve in the near future to incorporate Single Root I/O Virtualization (SR-IOV) technology for greater scalability and hypervisor bypass. Fabric Adapters are expected to evolve in the long term to incorporate Virtual Ethernet Bridging (VEB) and Virtual Ethernet Port Aggregator (VEPA) technology to take the switching load off the virtualization software and improve overall system performance.
Brocade will Lead the Migration to FAs. Brocade has a clear vision for aligning I/O adapter capabilities with the evolution of data center fabrics. Clearly the data center is evolving toward private and public clouds, environments where only Fabric Adapters will be equipped with the performance, VM-awareness and manageability for delivering I/O as a service. I expect Brocade to be the first vendor to introduce Fabric Adapters sometime in 2011. When this happens, Brocade will deliver the first 16Gbit Fibre Channel adapter technology, the first ASIC technology with native Ethernet and Fibre Channel integrated into a single core,
and the first vFL technology
