There's an interesting article on Infostor this week questioning the validity of SAS-based SANS -- not that the technology isn't viable or does not have some appreciable benefits, but whether anyone is really interested in yet another storage fabric.
Author Kevin Komiega points out that SAS is both a disk interface and an interconnect, a double role that does simplify network topologies a bit. But this is the era of converged storage networking; enterprises are prepping themselves for a new generation of network adapters that bring iSCSI and Fibre Channel under one roof. So why add even more complexity to the network?
Members of the SCSI Trade Association (STA) are quick to point out that SAS-as-interconnect is not the technology's main focus. But they do point out that SAS could be useful as a short-hop solution, say within a blade chassis or server cluster. And a company called Rancho Technology is working on expanders and other technologies that could be used to connect targets and initiators in the hopes of providing a solution for front-end storage subsystems.
Any kind of SAS-based storage network system would probably need to show some real advantage over existing protocols to make a dent at this late stage of the game. There's no question that the technology can be delivered -- it's only a matter of whether it provides any real value.