A method for operating a virtual network infrastructure, wherein a corresponding physical infrastructure comprises one or more physical infrastructure resources, includes monitoring utilization levels of one or more resource units of the one or more physical infrastructure resources for virtual resources requesting the one or more resource units; calculating average absolute resource utilization values based on the utilization levels for each of the virtual resources; calculating a reference resource of score (RRAS) for each of the one or more resource units of the one or more physical infrastructure resources, wherein the RRAS indicates an impact of the utilization of a reference resource unit on utilization of other resource units on a physical infrastructure resource using the calculated average absolute resource utilization values; and assigning resources by a virtual infrastructure controller (VIC) and/or a VIC-agent on a resource, based on the RRAS for the virtual resources.