Some implicit issues of network virtualization

An attempt is made to expose and elucidate some implicit issues of network virtualization. Various facets of the modern network function virtualization (NFV) trend are revealed. Contiguity of the virtual networking and NFV is discussed. The NFV sources and history are observed in interaction with server virtualization and virtual machines. “The sphere of interests” of the modern NFV technology is outlined. Mutual inclination of two actual network concepts — NFV and software-defined networking — is stated on the basis of the following common objectives: refusal of proprietary network equipment, commonality of the centralized control paradigm, and the spatial limitation within data centers (including software-defined data centers). A number of impartial obstacles in the NFV practical deployment are shown: necessity to massively replace available equipment, insufficiency of the standard support, impossibility to estimate cost efficiency, and absence of real precedents and successful implementation examples. Special attention is paid to the performance inadequacy of NFV solutions for data centers' networks.