Following up on our discussion of RDMA and 10 GbE Thursday, this is an interesting, if somewhat overlong, article on HPCwire discussing the need for greater scalability and reliability among 10 GbE switches to keep pace with the newest server adapters hitting the market.
With multicore CPUs, blades, virtualization and a host of other advances hitting the datacenter, 10 GbE switch port density seems to be stuck in neutral. As enterprise data needs continue to expand, many will have no choice but to turn to Fibre Channel and/or Infiniband, both of which support multiport mesh fabrics but are unfriendly to wider IP and Ethernet networks, not to mention killer expensive.
The main reason for this state of affairs is the plug-and-play convenience of Ethernet devices. Since they don't keep frame histories, data can get lost in a perpetual loop between ports. Things like the spanning tree protocol (STP) can help alleviate this problem, but you have to move up to Layer 3 switching, which costs a premium.
What's needed is a new set of algorithms that let switches deliver a multipath Ethernet fabric on Layer 2 that combines the speed and scalability of Infiniband and the resiliency of Fibre Channel. This piece sites Woven Systems working along those lines, and indeed the company drew big crowds at Interop last month with a Layer 4 switch. If a Layer 2 design can bring 10 GbE flexibility up without blowing current price points, that would certainly be a major development in enterprise networking.
Here's hoping they can pull it off.