Software-Defined Networking Technology
Software-defined networking (SDN) technology is a modern approach to networking that eliminates the complex and static nature of legacy distributed network architectures through the use of a standards-based software abstraction between the network control plane and underlying data forwarding plane, including both physical and virtual devices. This data plane abstraction provides a novel, standards-based approach to dynamically provision the network fabric from a centralized software-based controller. SDN technology enable dramatic improvements in your network agility and automation, while substantially reducing the cost of your network operations. Using an industry standard data plane abstraction protocol like OpenFlow, you are now free to use any type and brand of data plane devices, since all the underlying network hardware is addressable through a common abstraction protocol. Importantly, OpenFlow facilitates the use of "bare metal switches" and eliminates traditional vendor lock-in, giving you freedom of choice in networking like you have n other areas of your IT infrastructure such as compute and storage. SDN controllers also expose APIs northbound, which allow you to deploy a wide range of off-the-shelf and custom-built network applications — many of which were fundamentally not feasible prior to the advent of SDN.
Compared to legacy networking architectures that are vertically integrated from the underlying hardware, through the operating system, and into the network application functionality, the inherently open nature of an SDN represents a fundamental shift in power giving you choice, agility and automated network operations not previously possible.
The OpenFlow Protocol
The OpenFlow protocol is the only standards-based SDN protocol in the world to abstract the network control plane (where forwarding decisions are made) from the network data plane (where packets are forwarded), which enables you to create a single network control policy that universally programs the entire network fabric. OpenFlow enables a central controller to remotely provision the underlying data plane device forwarding tables in a common, scalable way, and eliminates the vendor-specific, proprietary nature of legacy networking equipment. Specifically, OpenFlow enables automation through a centralized software controller that eliminates the need to program devices and interfaces for every network service request. And, for the first time in the history of networking, it provides you with flexibility and choice in networking vendors without re-architecting your entire network around vendor-specific protocols. In short, OpenFlow represents the most transformative standards-based protocol to hit the networking industry in over 20 years.
The OpenFlow protocol is managed by the Open Networking Foundation (ONF), which was an outgrowth of principal research done at Stanford University’s Clean Slate Program led by Big Switch Networks founder, Guido Appenzeller. The ONF, a non-profit user-governed consortium, has now grown to include some of the largest users in the world, including Google, Facebook, Yahoo!, Deutsche Telekom, Verizon and Goldman Sachs. Given the explicitly user-driven governance model of the ONF, the OpenFlow protocol is not subject to conventional vendor politics and manipulation that plagues other vendor-controlled industry standards bodies.
Network virtualization is an SDN technology application that creates unmatched network agility and dramatically reduces costs of network operations by automating network provisioning for both increasingly dynamic virtual workloads as well bare metal workloads. A network virtualization program eliminates the conventional shortcomings and time consuming provisioning tasks related to legacy network segmentation technologies, like switched VLANs, routed subnets, and firewall ACLs. Alternatively, an SDN-based network virtualization application supports arbitrary assignment of IP/MAC addressing schemes, while at the same time automating network configuration tasks and enforcing expected network segmentation. Network virtualization leverages the OpenFlow protocol to dynamically and automatically provision virtual network segments and virtual routing services on both physical and virtual networking devices. You can automatically provision network security policies through a cloud orchestration platform, like OpenStack, or automatically assign workloads according to workload attributes like MAC, subnet, VLAN, IP protocol, or other attributes. Network virtualization applications eliminate the time consuming provisioning process required with legacy networking gear, enable unmatched network agility, and dramatically reduce the cost of network operations.