A software-defined video network (SDVN) is a piece of networking equipment that manages and distributes video traffic by software rather than hardware. SDVNs use containers such as the MPEG Encapsulation Format or H.264 to encapsulate video payloads and routes them accordingly to an intended device…
As video is transforming into an essential business task, it is imperative that companies are able to utilize the benefits of video technology in order to successfully facilitate the required business processes. As a result, businesses are increasingly using software-defined video network technology in efforts to improve their efficiency.
Software-Defined Networking (SDN) is an approach to networking that uses software-based controllers or application programming interfaces (APIs) to communicate with underlying hardware infrastructure and direct traffic on a network.
This model differs from that of traditional networks, which use dedicated hardware devices (i.e., routers and switches) to control network traffic. SDN can create and control a virtual network – or control a traditional hardware – via software.
While network virtualization allows organizations to segment different virtual networks within a single physical network, or to connect devices on different physical networks to create a single virtual network, software-defined networking enables a new way of controlling the routing of data packets through a centralized server.
Why Software-Defined Networking is important?
SDN represents a substantial step forward from traditional networking, in that it enables the following:
- Increased control with greater speed and flexibility: Instead of manually programming multiple vendor-specific hardware devices, developers can control the flow of traffic over a network simply by programming an open standard software-based controller. Networking administrators also have more flexibility in choosing networking equipment, since they can choose a single protocol to communicate with any number of hardware devices through a central controller.
- Customizable network infrastructure: With a software-defined network, administrators can configure network services and allocate virtual resources to change the network infrastructure in real time through one centralized location. This allows network administrators to optimize the flow of data through the network and prioritize applications that require more availability.
- Robust security: A software-defined network delivers visibility into the entire network, providing a more holistic view of security threats. With the proliferation of smart devices that connect to the internet, SDN offers clear advantages over traditional networking. Operators can create separate zones for devices that require different levels of security, or immediately quarantine compromised devices so that they cannot infect the rest of the network.
The key difference between SDN and traditional networking is infrastructure: SDN is software-based, while traditional networking is hardware-based. Because the control plane is software-based, SDN is much more flexible than traditional networking. It allows administrators to control the network, change configuration settings, provision resources, and increase network capacity — all from a centralized user interface, without the need for more hardware.
There are also security differences between SDN and traditional networking. Thanks to greater visibility and the ability to define secure pathways, SDN offers better security in many ways. However, because software-defined networks use a centralized controller, securing the controller is crucial to maintaining a secure network.
How does Software-Defined Networking (SDN) work?
Here are the SDN basics: In SDN (like anything virtualized), the software is decoupled from the hardware. SDN moves the control plane that determines where to send traffic to software, and leaves the data plane that actually forwards the traffic in the hardware. This allows network administrators who use software-defined networking to program and control the entire network via a single pane of glass instead of on a device by device basis.
There are three parts to a typical SDN architecture, which may be located in different physical locations:
- Applications, which communicate resource requests or information about the network as a whole
- Controllers, which use the information from applications to decide how to route a data packet
- Networking devices, which receive information from the controller about where to move the data
Physical or virtual networking devices actually move the data through the network. In some cases, virtual switches, which may be embedded in either the software or the hardware, take over the responsibilities of physical switches and consolidate their functions into a single, intelligent switch. The switch checks the integrity of both the data packets and their virtual machine destinations and moves the packets along.
Benefits of Software-Defined Networking (SDN)
Many of today’s services and applications, especially when they involve the cloud, could not function without SDN. SDN allows data to move easily between distributed locations, which is critical for cloud applications.
Additionally, SDN supports moving workloads around a network quickly. For instance, dividing a virtual network into sections, using a technique called network functions virtualization (NFV), allows telecommunications providers to move customer services to less expensive servers or even to the customer’s own servers. Service providers can use a virtual network infrastructure to shift workloads from private to public cloud infrastructures as necessary, and to make new customer services available instantly. SDN also makes it easier for any network to flex and scale as network administrators add or remove virtual machines, whether those machines are on-premises or in the cloud.
Finally, because of the speed and flexibility offered by SDN, it is able to support emerging trends and technologies such as edge computing and the Internet of Things, which require transferring data quickly and easily between remote sites.
What are the different models of SDN?
While the premise of centralized software controlling the flow of data in switches and routers applies to all software-defined networking, there are different models of SDN.
- Open SDN: Network administrators use a protocol like OpenFlow to control the behavior of virtual and physical switches at the data plane level.
- SDN by APIs: Instead of using an open protocol, application programming interfaces control how data moves through the network on each device.
- SDN Overlay Model: Another type of software-defined networking runs a virtual network on top of an existing hardware infrastructure, creating dynamic tunnels to different on-premise and remote data centers. The virtual network allocates bandwidth over a variety of channels and assigns devices to each channel, leaving the physical network untouched.
- Hybrid SDN: This model combines software-defined networking with traditional networking protocols in one environment to support different functions on a network. Standard networking protocols continue to direct some traffic, while SDN takes on responsibility for other traffic, allowing network administrators to introduce SDN in stages to a legacy environment.
SDN elements
An SDN architecture delivers a centralized, programmable network and consists of the following:
- A controller, the core element of an SDN architecture, that enables centralized management and control, automation, and policy enforcement across physical and virtual network environments
- Southbound APIs that relay information between the controller and the individual network devices (such as switches, access points, routers, and firewalls)
- Northbound APIs that relay information between the controller and the applications and policy engines, to which an SDN looks like a single logical network device
SDN adoption
SDN has seen wide adoption across data centers (64%), WANs (58%), and access networks (40%). For more information on SDN trends, see the 2020 Global Networking Trends report.
SDN and IBN
SDN serves as a foundational element of a comprehensive intent-based networking (IBN) architecture. SDN has been limited to automated provisioning and configuration. IBN now adds “translation” and “assurance” so you can automate the complete network lifecycle and continuously align the network to business needs. Watch our Beyond SDN webinar recording to explore more ways intent is changing how we network.
Conclusion:
Today’s most expensive networking technology uses a hardware architecture, but with emerging technologies such as Software Defined Networking (SDN), you can build a flexible and cost-effective network with next-generation hardware architecture.