Broadcom Raises the Bar for CNA Technology

Broadcom recently unveiled the BCM578x0, its latest generation of 10Gbit Ethernet ASICs for LAN-on-Motherboard (LOM) and NIC applications, and the first in a new class of converged network adapters (CNAs), or converged NICs (C-NICs). The new family of ASICs includes several innovations that raise the bar for CNA technology and provide a glimpse at the capabilities of the next generation of high performance Ethernet adapters.

The quad-port BCM57840 delivers twice the port density of competitive dual-port ASICs, in a footprint smaller than any competitor's smallest dual-port ASIC. In addition, the high-performance BCM57840 hardware is remote direct memory access (RDMA)-ready, which positions the product line to serve as the industry's first LOM/NIC platform for complete LAN, iSCSI SAN, Fibre Channel over Ethernet SAN and low-latency high-performance computing (HPC) network convergence. Looking forward, this class of Ethernet controller with 40Gbits of bandwidth has the potential to serve as a 40Gbit Ethernet host adapter or a 40Gbit Ethernet iSCSI storage port.

The advanced technology in the BCM578x0 is the first in a new class of network controllers you can expect to see later this year in new high-performance servers. There are five key reasons why data center managers will need the capabilities of this new generation of LOM and NIC in their virtualized servers:

1. Servers are set to drive high throughput on multiple 10Gbit Ethernet ports with eight- and 12-Core Processors. The days when servers didn't have the power to drive 10Gbit Ethernet traffic are gone. The new generation of eight- and 12-core processors from Intel and AMD are designed to drive I/O to and from servers loaded with virtual machines. According to Intel, its new eight-core Xeon 7500 can deliver up to 20 times the performance of servers with single-core processors.

2. Servers are set to scale 10Gbit Ethernet ports with PCIe 3.0. Another reason the capabilities of this new generation of LOM and NIC will be coveted in data centers is because they're speed-matched with the latest generation of PCIe 3.0 I/O interconnects, which will appear in new servers beginning in 2011. The bi-directional bandwidth of an x8 PCIe bus is 64Gbits, which means a single bus can support up to six 10Gbit Ethernet adapters, or one 40Gbit Ethernet adapter, running at full speed.

3. Virtualized servers require full offload. VMware's inbox support for 10Gbit Ethernet iSCSI offload in 2010 was an acknowledgment that CPU should be preserved for virtual machines, and that virtualized servers require adapters with full offload. Best practices in the future will include deployment of 10Gbit Ethernet adapters that offload all network protocol and virtual switch processing, including TCP/IP, iSCSI, Fibre Channel over Ethernet, RDMA and Virtual Ethernet Bridging (VEB).

4. Virtualized servers require more system memory. As the average number of virtual servers per physical server grows, so does the average amount of memory configured per physical server. The new generation of Ethernet LOM ASICs is critically important to server designers and administrators because it frees motherboard space for more system memory.

5. Complete convergence on Ethernet requires lower latency Ethernet. The current generation of 10Gbit Ethernet adapters and switches supports Data Center Bridging (DCB) and Fiber Channel over Ethernet for network convergence. However, complete network convergence requires support for the the RDMA protocol used for low-latency traffic found in HPC clusters. When this final convergence building block is put into place, LANs, NAS, iSCSI SAN, Fiber Channel over Ethernet SAN and HPC cluster traffic can converge onto Ethernet. The BMC57840 is designed to support hardware offload of RDMA, making it the first LOM/NIC ASIC capable of supporting offload of network protocol processing and VEB, the features needed for complete network convergence.

The bottom line is that Broadcom has raised the bar for its competition in the CNA market. To stay in the game, high-end Ethernet LOM/adapter ASICs from Brocade, Chelsio, Emulex, Mellanox, QLogic and SolarFlare need to support 40Gbits of bandwidth, at least four ports and full offload, including VEB and some form of the RDMA protocol.