software-defined networking

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software-defined networking

An approach to designing, building and operating large-scale networks that is essentially based on programming the forwarding decisions in routers and switches via software from a central server. Software-defined networking (SDN) differs from traditional networking, which requires configuring each device separately and which relies on protocols that cannot be altered.

The primary applications of SDN have been in wide area network (WAN) traffic engineering, datacenter network virtualization and monitoring. SDN gives network administrators the flexibility to customize their networks for their traffic requirements.

Separate the Control from the Forwarding
SDN routers and switches ("bare metal devices") perform basic forwarding functions under program control from a central server that commands the hardware via the OpenFlow interface. Fewer built-in protocols and vendor-specific features in the hardware mean less complexity and greater reliability, and central control makes setting up new networks, as well as making changes, much easier than deploying scripts to each device or waiting for vendors to update their firmware. Software control also enables the creation of innovative forwarding algorithms, and simulating and testing them is simplified, because the hardware can be easily emulated. See SD-WAN.

SDN and OpenFlow
The OpenFlow protocol, which is the basic instruction set in SDN routers and switches, was standardized in 2009, and the first large-scale deployments occurred starting in 2011. See OpenFlow and NFV.

Example From Big Switch Networks
This shows the separation of the software (control plane) from the forwarding (data plane). Providing network virtualization and monitoring, Big Virtual Switch and Big Tap communicate with Big Network Controller (an SDN operating system). Big Network Controller controls the virtual hypervisor switches and physical switches via OpenFlow commands. (Image courtesy of Big Switch Networks, Inc.,
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References in periodicals archive ?
The post How to improve visibility in the age of SDN appeared first on
SDN makes it easier to introduce and deploy new applications and services rather than the classical hardware-dependent standards.
This SDN will enable Jazz to move from current manual node-level working on IP routers to a fully automated E2E dynamic adjustments in capacity, priority, routing, resilience and maintenance related shutdowns.
Speaking about the SDN deployment, Khalid Shahzad, CTO Jazz, said, 'Digital transformation is forcing companies to be agile and move with speed, and the network needs to be equally agile and fast.
The seven elementary schools are SDN Jayamukti 01, SDN Sertajaya 05, SDN Mekarmukti 06, SDN Pasir Gombong 01, SDN Harjamekar 04, SDN Wangun Harja 02 and SDN Pasir Sari 04.
This new SDN brain will accomplish all of this efficiently through an end-to-end high-level visibility created by connecting it to all individual routers, the statement added.
Even though SDN and NFV are closely related, yet differs from each another.
SDN is a developing architecture that enables applications and the network to communicate to each other using application program interfaces (APIs).
SDN is approaching adoption by an early majority of enterprises and will compose nearly 40% of global enterprise network infrastructure revenue (roughly $12.7 billion) by 2020, TBR's latest Enterprise SDN Market Landscape research shows.
According to Allied Market Research, the SDN market is expected to reach $132.9 billion by 2022.