Monday, February 15, 2010
The metaphor of the network as a "cloud" is appealing in its simplicity. The cloud abstraction imagines the network as a uniform communication medium in which location is no longer important. While a well provisioned and managed network can create this illusion, the reality is that networks are far from uniform and effective network visibility and control is required to maintain the illusion.
Using a cloud related metaphor to illustrate the importance of visibility; anyone who has driven in the fog knows how disorientating and dangerous a lack of visibility can be. Ignoring the need for visibility into network traffic in the data center risks turning the network cloud into a dense fog where the dynamic, efficient and flexible services promised by virtualization and cloud computing cannot be realized.
Network convergence to a single high-speed switched Ethernet fabric simplifies connectivity, while the sFlow standard implemented by most vendor's Ethernet switches, simplifies management by providing the network-wide visibility needed to manage network resources and deliver cloud services.