Cisco has announced a blade addition to its Nexus line of data centre switches designed to aggregate multiple physical x86 blade servers from various vendors into a 10G Ethernet fabric.

The Nexus 4000 is the first blade switch in the Nexus line, which also includes the Nexus 7000 core switch, the 5000 top-of-rack switch, the 2000 fabric extender and the 1000V software-based virtual switch. The 4000 is intended to fit inside a blade server system enclosure and aggregate multiple 1G server NIC connections into a 10G pipe for connection to and from the Nexus 5000 and 7000 top-of-rack and core switches.

The Nexus 4000 supports the same NX-OS converged LAN/SAN operating system as the rest of the Nexus family, and Cisco's MDS SAN switch line. This is intended to provide consistency across the data centre as well as scale, high availability, fault tolerance and uniform management, Cisco says.

The Nexus 4000 supports FibreChannel and FibreChannel over Ethernet, and IP-based iSCSI or Network Attached Storage over Ethernet Data Center Bridging specifications for converged LAN and storage access from the server. It features a specialized ASIC for low latency and lossless operation in a virtualised environment, said Cisco.

It can work in conjunction with Cisco's Nexus 1000V virtual switch, which resides on blade servers running VMware's ESX 4.0 virtualisation software. The 1000V aggregates virtual machine images from a single server while the 4000 aggregates multiple physical blade servers, Cisco says.

The Nexus 4000 will be sold to Cisco's OEM customers who will rebrand it and then sell it to end users. Cisco expects its existing base of Catalyst blade switch OEMs to purchase the new Nexus blade switch.

Since it is being developed for blade server vendors, Cisco says it will leave product details, availability and pricing up to those particular vendors. The new switch will compete with HP's new 6120XG and 6120G/XG blade switches, and 6- and 10-port BNT switches from Blade Network Technologies, which are resold by IBM.

The Nexus 4000 is a small piece of a broader strategy outlined by Cisco for its data centre and FCoE initiatives. As part of that strategy, Cisco is positioning its MDS FibreChannel SAN switches as evolutionary elements in the transition to unified data centreswitching fabrics.

In that vein, Cisco says it plans to unveil FCoE modules for both the MDS and Nexus 7000 switches; a 16Gbit/s FibreChannel MDS switch; and an 8Gbit/s FibreChannel expansion module for the Nexus 5000 FCoE switch. These will likely come in the first half of 2010, Cisco officials said.

These will be piece parts in Cisco's plan to incrementally evolve data centres to FCoE by starting at the server edge/access point and deepening the immersion into the aggregation and core areas of the data centre network.