?Botero and et al?. ?\cite{Ref004} introduce hidden hops constraints?. ?They believe each virtual link which is embedded on a substrate path?, ?needs the CPU demand in the intermediate nodes (hidden hops) of the substrate path and this problem has not been taken into account as an important parameter in related works?. ?To address this problem the author of \cite{Ref004} add hidden hops constraint to a heuristic algorithm in their proposed method?.

?In Ref \cite{Ref005} VNE problem was formulated as a mixed integer linear programming problem and was introduced stochastic bandwidth demand to solving it?. ?In VNE problem?, ?physical node reusable mapping (PNRM) shows a virtual node should be mapped on a single substrate node and each pair of the virtual node in the same virtual network should be mapped on separated substrate nodes?. ?But ref \cite{Ref006} to reach high acceptance ratio and high revenue?, ?ignored PNRM and has maps one virtual node in several substrate nodes?. ?Abedifar and Eshghi \cite{Ref007} propose a virtual link mapping approach that routes the virtual links on the substrate infrastructure and assigns the available wavelengths to the resulting light paths trying to minimize the used wavelengths per physical link?. ?Their work is the first optical network field and they introduce some open problems?, ?e,g?. ?how to include the effect of physical layer Impairment (PLI) degradations in the optical VNE feasibility?, ?especially in larger networks scenarios?. ?Most of uncoordinated VNE algorithms?, ?complete node mapping phase with node ranking?, ?large to large node mapping or priority based node ranking (base on nodes status like degree and local neighbors) and complete link mapping phase with the shortest path?, ?k-shortest path or random path with optimization?. ?Leivadeas et al?. ?\cite{Ref008} are extended the scope of the VNE paradigm by including ?socio?-aware features?. ?Socio-aware features are features which are related with substrate network?, ?e,g?. ?accounting?, ?social and load?.

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