A.Class Of Service (COS) Tagging
C.User-defined network resource pools
Class of Service tagging and user-defined resource pools are deprecated in NIOC3.
In vSphere 6.0, version 2 and version 3 of the Network I/O Control coexist. The two versions implement different models for allocating bandwidth to virtual machines and system traffic. In Network I/O Control version 2, you configure bandwidth allocation for virtual machines at the physical adapter level. In contrast, version 3 lets you set up bandwidth allocation for virtual machines at the level of the entire distributed switch.
When you upgrade a distributed switch, the Network I/O Control is also upgraded to version 3 unless you are using some the features that are not available in Network I/O Control version 3, such as CoS tagging and user-defined network resource pools. In this case, the difference in the resource allocation models of version 2 and version 3 does not allow for non-disruptive upgrade. You can continue using version 2 to preserve your bandwidth allocation settings for virtual machines, or you can switch to version 3 and tailor a bandwidth policy across the switch hosts.