Doubts Cast on the Converged Network

Is the converged network really the path to lower costs and more efficient data center operations?

That notion took a major hit this week after Gartner issued a blockbuster report arguing that a single infrastructure for data and storage may not be in the enterprise's best interests.

The study, issued by research VP Joe Skorupa, is bound to ruffle a number of feathers in the networking industry, which has been feverishly touting 10 GbE, Fibre Channel over Ethernet (FCoE) and other technologies as a means to eliminate redundant network wiring and devices, at once simplifying data infrastructure and lowering operating costs. Skorupa argues that a single network will likely increase the number of switches and ports because it will be tasked with carrying the load of more simultaneous users, leading to a complicated grid of interconnect points that wouldn't exist under individual LAN and SAN architectures.

Management of this beast will be a major hassle as well, Skorupa argues. With multiple lines of traffic vying for ports, line cards and switches, expect congestion to increase -- resulting in higher latency and diminished overall performance. New standards like TRILL (Transparent Interconnection of Lots of Links) may provide some relief but probably won't be available for a few more years.

One study is not likely to provide the definitive word on converged networking, however, and top vendors are moving their product lines full bore toward converged environments. Cisco, for example, just announced the next phase of its Borderless Networks strategy, which combines LAN/SAN convergence with mobile infrastructure, collaboration technology and new services intended to create a single data center communications architecture. Key to the strategy is a new line of fixed-switching devices that incorporate 10 GbE, Power over Ethernet (PoE) and integrated virtualization and video capabilities.

Meanwhile, storage and networking companies are joining forces to make it easier for their systems to work together in a unified environment. NetApp, for one, recently added support for Emulex' OneConnect Universal converged network adapter (CNA) to its line of Ethernet storage appliances. The deal gives NetApp the ability to tap into both Ethernet and Fibre Channel infrastructures through the FCoE standard.

So who's right in all this? My guess is there is some truth in both arguments. Network convergence will reduce the number of switches and the amount of redundant cabling present in most data centers. But there is reason to be cautious of a single, unified network growing out of control, reintroducing the very problems that convergence was supposed to get rid of.

In the end, it comes down to the skill of the network architect. A little convergence will produce a number of benefits, but be careful not to enjoy too much of a good thing.