It didn't get as much attention as VMware's higher-level and less-specific announcements, but the most significant technology announcement coming out of VMworld this week may have nothing to do with VMware's vision of the future or competition with Microsoft. The most important thing may be the result of its partnership with Cisco and an advance in Cisco's virtual-network-switch technology called the Virtual Network Link (VN-Link). Pitched by Cisco as a replacement for VMware's own VM switching capability, Cisco's VM-Link is designed to give network and server administrators a way to establish the security, storage and networking links for a particular VM and have that configuration move along with the VM when it's migrated from one physical host to another. VMware's VMotion allows server administrators to migrate, reprovision or relaunch servers pretty much at will within an ESX virtual infrastructure. It doesnt automate the process of configuring all the network, storage and security software, however. VN-Link is designed to bridge that gap, automating the process of applying the same network, storage and security configurations to a VM after it's moved from one domain to another. That should allow administrators to manage not only the VMs, but also their storage, network and security configurations by policy instead of by hand. That not only makes it a lot easier to manage the VMs, it makes the job of network and storage administrators a lot easier by allowing them to reallocate their own resources to accommodate changes within the virtual environment. VN-Link is designed to let them automatically provision network, storage and security for VMs, whether mobile or stationary, and provide diagnostic tools to check on the health and policy compliance of the VMs they're already tracking. It will also provide a way to bridge the often-contentious organizational divide between administrators responsible for server farms or virtual infrastructures and those responsible for the networks, storage and security systems on which the VMs depend.VN-Link will be delivered both as part of Cisco's Nexus 1000V switch and as a software-only edition that will be integrated with VMware's vNetwork Distributed Switch\u2014a more sophisticated version of VMware's own virtual switch technology. VN-Link itself won't do much to control virtual-server sprawl, as some pundits are predicting. Sprawl comes from not being able to say 'no' to users who want another virtual server, then another, then another.But being able to connect the applications that control the location, behavior and access rights of all the VMs in an infrastructure does give administrators a better idea of what VMs are out there, what they're allowed to do, and whether there are network, security or storage accounts that are still open and available, even though the VMs for which they were created have moved on (in the physical, virtual or metaphysical sense).Virtual data center operating systems, cloud computing, dynamic information technology, ultra-flexible virtual desktop infrastructures are all good and interesting concepts. Some of them eventually will do a lot to change the way IT in general and data centers in particular actually function. But a tool that lets you set policies for a server, then move it around without ever losing the connection to the networking, security or storage management applications that make a virtual server work? That's better than visionary; that's useful.