Single control plane vs separate control planes

[Alex]

Hello.

One of the most significant differences between VSS and vPC is that in case of using VSS, virtual switch has single control plane. And in case of vPC there are always two separate control planes - one per vPC peer switch. So my question is: are there any advantages in having two seperate independent control planes? Why Cisco made completely new feature (vPC), and not just migrate and evolve VSS in Nexus series somehow?

Thanks in advance.

Best regards, Alex.

[Jianbin Huang]

As a user I also prefer single control plan while vPC has so many restriction.yep, it can eliminate the STP, but it also bring the complex and  new restriction  to our network.

The only reason I came out for why cisco made this new protocol is:

Single control plan require more resource to handle all other node, for example the sup-1 may double the CPU/RAM etc. capacity to achieve this goal. 

The other reason is separate control plan has lower delay (latency) than single control plan while handling some process (such as port up/down).