Recently there are many confusion about these new terms VN-Link & Cisco nexus 1000V which been widely communicated to the IT user groups. Where were the confusion come from? Most of the time, we are getting confuse about what is VN-Link meant by Cisco. Below is some short description you may want to refer to.

Cisco Nexus 1000V is a enhance virtual distributed virtual switch which integrate to the VMware vSphere 4. With Cisco Nexus 1000V, you will contain VSM and VEM, which VSM will be the virtual appliances that host the management of Nexus 1000V, and VEM will be installed on each ESX host that been connected to the Nexus 1000V.  I will not go in too details about Nexus 1000V in this post as my intention is to clear up the confusion on the VN-Link meant by Cisco.

6 months ago, this new term had come to my career while someone had claimed that the VN-Link will allow virtual machine to direct interact to the physical IO devices on the PCI-E without hypervisor in place. Well, this features had been included in VMware for quite some times in vSphere 4 by using the functionality call VMDirectPath I/O. But while doing this, you will lose the functionality of VMotion, and most users will not go for this due to the limitation on VMotion. Since this is new, no right or wrong, I decided to leave it for a while and further research to understand it.

After many round of discussion and reading on the blog and white paper, finally I have the answer I want now. VN-Link is the product name for a family of products, does not specifically refer to any one product so forget the idea of hardware vs. software implementation, etc.  Think of the Nexus family of switches: 1000v, 2000, 4000, 5000, 7000.  All different products solving different design goals but are components of the Data Center 3.0 portfolio from Cisco.  In VN-Link it contains Cisco Nexus 1000V, Hypervisor Bypass with Direct Path I/O, Pass Through Switching, Virtual Interface card & VNTag. If you had done the administration or implementation on Cisco UCS, Nexus 1000V, Nexus 5000 & 2000, you should familar with all these term that I mentioned here.

For more details information, I will recommend the Unified Computing Blog who had done the good explanation to described further in details for the VN-Link technology.