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In order to support these requirements, in the last few years, a few emerging technologies and concepts have appeared and disrupted how network equipment is designed, and how networks are built and operated: hardware commoditization and disaggregation of software from hardware and of software itself, extensive use of open source (Linux), Software Defined Networking (SDN), Network Functions Virtualization (NFV) and DevOps.
<suggested addition - Ranny Haiby : The The telecommunications industry is going through one of its major transformations, becoming a digital, software focused business. Communications Service Providers (CSPs) require higher degree of agility that was traditionally lacking in their mostly hardware based business. In the past, offering new services required changing the physical structure of the network and often took as long as months or even years. CSPs identified the need to move to software, and especially open source software as the only way to deal with these new demands. Open source software has proven to be a perfect platform for rapid innovation in many domains such as operating systems and enterprise software. The time is right to leverage these advantages in the networks operated by the CSPs. The projects under the Linux Foundation Networking umbrella provide the open source building blocks for building the modern networks.>