SC2012VMM SP1 - How to Create a Internal and Private Networks on Hyper-V

Hi,

There is an article about how to create Virtual Networks in SC 2012 VMM:
http://social.technet.microsoft.com/wiki/contents/articles/3140.create-networks-with-vmm-2012.aspx

Would anybody be so kind to explain how to create virtual networks in SC 2012 VMM SP1? Particluarly, how to be able to create Internal and Private Networks on Hyper-V from SCVMM Console?

Thank you very much in advance!