SDN and NFV allow you to simplify network configuration, scale networks and services on demand, automate network management, increase the capacity of the physical infrastructure by overlaying virtual, reduce CAPEX and OPEX , and in the future - quickly reconfigure the business for current tasks.The first large SDN was implemented in 2012 by Google based on its own design of switches. Thus, she managed to remove those restrictions that are inherent in the solutions used by traditional operators. Traffic is redirected between the data centers as it is convenient and profitable at the moment. In addition to Google, SDN technology is used by NTT, Pertino, AT&T, Telecom Italia and several other companies. Two strategic directions for the implementation of SDN, NFV and clouds are emerging.
The first is related to improving network efficiency and service flexibility. The main goal is to reduce network operating costs and reduce time to market. The second is aimed at taking advantage of a combination of new business opportunities. The goal in this case is different - the formation of new differentiated cloud services and dynamic, depending on the current demand profile, their provision. The first path goes to companies such as the German Deutsche Telekom and the Spanish Telefonica, the second - Japanese NTT and American AT&T.
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