SDN Technologies FAQs

FAQs / Overview of SDN Technologies

Pluribus Networks offers leading software defined networking technology solutions and can help you understand what SDN offers and how SDN integration with networks works. This guide will help you see what SDN can bring to your network.

What Is SDN Technology all about?

Software defined networking technology provides a way for many networks to become more agile and adaptive by scaling support for today’s dynamic, high-bandwidth applications. SDN separates the physical infrastructure from network control and forwarding functionality, so that the network itself becomes more directly programmable.

A few key points of SDN integration within existing networks:

  • Network controls are directly programmable so that you can completely manage all forwarding functionality, plus other network activities.
  • Network intelligence is centralized within SDN controllers, giving you a single platform or dashboard to maintain a global look at the network. Policy enforcement aims to work on local and broad levels.
  • There is a reliance on open standards, and SDN technologies also perform best when developed to operate in vendor-neutral settings. Today’s leading tech can operate and adjust to meet your specific and existing hardware.
  • SDN simplifies your network design by providing instructions from controllers instead of individual devices and protocols, which some vendors can set and limit on older networks.
  • Its heart is agile. The systems are designed to grow, move controls and adjust when network demands change. This can be due to growth or increased need, both at local levels or on network-wide levels.
  • Software defined networking technology solutions are designed to integrate with a variety of different software and hardware options. This is a core tenet of SDN technology.

This design focus helps software defined networking deployment address the dynamic needs of modern networks. Those networks still considered “conventional” are falling down in environments like data centers and large enterprise campuses because they struggle to adjust with processing, storage and other networked element needs.

What Is Driving Today’s SDN Technologies?

The adoption of modern, compute and storage intensive technologies and applications such as Big Data, Virtual Desktop Infrastructure, East-West Security and even DevOps wanting more agility – all are chief reasons we see brands looking at software defined networking integration within their existing data hierarchy and architecture. In order to manage the ever-growing nature of these demands upon the network, SDN technologies are stepping up to fill in the gap.

A few other growth areas in modern networking design, best practices and evolution are also guiding the adoption of SDN. Here are a few reasons your network might consider looking at SDN:

  • Customers want cloud support. Your customers and users are going to demand that your applications are accessible on-the-go, and this type of cloud support inherently brings new demands for making your processing, infrastructure, data and other networked resources in the cloud.
  • Application programming interfaces (APIs). Software defined networking technology solutions are using new ways for abstraction to support programmable infrastructure. One area of growth is in APIs, because they can be inserted into the controller and used by applications to manage access, address devices and provide communication.
  • Traffic is shifting. Data centers and networks are moving every day because of the cost of land, location of traffic and remote areas offering centralized distribution spokes in the wheel. As traffic patterns adjust with varying demands in new areas, many companies can save money by simply adjusting existing resources instead of trying to build new, inflexible infrastructure in areas of projected growth.
  • IoT is going to change your data streams. We often think of scalability as adjusting to the flood of data from growth, but using familiar channels. However, the rise of new, internet-enabled devices is bringing new data from new channels and with new ways of interacting. All of this demands flexibility and scalability of networks, central processing and more.
  • IT isn’t just yours anymore. Devices that staff use are trending more and more to be personal devices and those that must work in multiple scenarios. The growth of BYOD means that your network needs controls and governance in place that can adjust to any device, without completely controlling and managing that device.

These drivers are all important to you because they’re making it easier for SDN controls and other network elements to work with existing infrastructure.

Can SDN Work with My Existing Network?

If you’re looking here, you’re probably asking yourself the most common question we hear: “Will SDN work with my existing network, and can I afford it?”

Software defined networking integration is extremely common and the ability of SDN technology to operate with white box solutions actually saves many of our partners significant money. You’re likely using some form of a software-centric network, where switches or routers run an OS specifically designed to make the most of your networked equipment.

Software-centric elements give you support for virtualization, modularity, process isolation and more. SDN integration with networks like this is very simple and is often a matter of transferring controls to a specific network element or integrating APIs that give your network devices instructions and make better use of their capabilities.

The best news for you is that network management elements, virtualization management and APIs to manage both capabilities are being rapidly developed and new offerings are designed to work with older equipment. So, for you, the opportunities are growing.

SDN Overlays vs. Underlays

SDN overlays and underlays are not mutually exclusive – in fact, you can deploy both in your network. But the key takeaways to focus on are that overlays are a means for system engineers to provide connectivity to virtual infrastructure, while underlays transform how the network is operated.

Overlay networks are software deployments, typically run on hypervisors at the compute layer, that put a selected flow-based path at its end points – and then tunnels through.

Underlay networks operate directly at the switch (physical) layer, and allow you to software-define the entire networking functionality.

Traditional Networking – what are the basics in light of SDN?

The network configuration we consider “traditional” is still used by many networks today. There are two main things that will let you know if your network is in a traditional layout:

  1. Functions in the network are typically implemented in a dedicated device for each purpose. These devices include your switches, routers and application delivery controllers.
  2. Functionality within each device is executed in a specific piece of dedicated hardware. This will often make the use of application specific integrated circuits.

Traditional network devices have a control plane that gives them desired information which they use to create a forwarding table, and the data plane references this forwarding table to make decisions. Frames or packets delivered to the device are then sent on based on the control plane’s rules, and both of these planes exist within the networking device itself.

Development of a traditional network requires specific, planned steps that tend to require an IT administrator to be present even during maintenance. Traditional networking often requires manual configuration of devices on a device-by-device basis before network management tools can be applied for device-level management.

If a traditional network uses hardware from multiple vendors, each individual element will need to be configured to work with other devices and deployments, but much of this work will have to occur on a case-by-case basis with direct configuration.

Software Defined Networking – what is it, in light of Traditional Networking?

Software defined networking (SDN) is the virtualization of your network by decoupling hardware from software, making adjustments on the two device planes we discussed in the traditional networking setting.

The control plane is removed from the device and is placed on what is essentially a layer of networking software. The data plane stays on the networked hardware so that it can still execute commands and directions from the control plane.

What this means for your network is that the hardware no longer controls data paths, allowing you to build out centralized software that makes decisions and creates a virtual control mesh in the network. This is network virtualization, and it operates very similarly to server virtualization.

SDN allows a network to be flexible to change data handling and flow when your business needs change. If you also integrate network automation controls, such as APIs, then your controller can deliver instructions throughout your network quickly and without the need to understand command line and code for each different vendor whose equipment you’re using.

What are the Benefits of SDN over Traditional Networking

When looking at traditional networking and software defined networking, there are a lot of differences, both large and small. There are two big business benefits to consider when making the traditional networking vs. software defined networking choice:

  • Data flow optimization. Data flows play a significant role in traditional networking and software defined networking. SDNs will perform a little better for business needs, especially in data centers, because the SDN controller is able to identify and use multiple paths per data flow. Traditional networks are typically stuck with a single path and don’t allow you to split traffic across multiple nodes. Using multiple nodes and adjusting flow based on traffic size can help maintain a quick network and prevent a slowdown or bottleneck.
  • SDN and traditional networking both need to have a network configuration that supports your business goals. Traditional networks are configured through largely manual processes on a per-device scheme. The core of SDN support is that devices can be configured automatically and adjusted automatically, improving network responsiveness and preventing you from taking up all of the time of your system admins whenever any network element needs to change.

Thus, flexibility and speed are two big differences between SDN and traditional networking.

In addition, SDN is usually able to deliver significant cost savings by simply reducing the amount of spend you have to put toward infrastructure — you’re optimizing devices to sometimes run multiple different use cases dynamically as your traffic changes. You’ll get the most out of existing devices without needing to purchase and install new equipment for each possible use case.

With that cost savings also comes increased visibility, because your system administrators are working from a viewpoint of overall network functionality. They can then adjust resources where needed, pre-stage commands for quick responses and even automate control changes and flow changes so that your network automatically scales and adjusts.

What might be a summary of SDN vs. Traditional Networking?

SDN vs. traditional networking comes down to a choice between time and flexibility. Modern networks need to adjust to new demands, and often have to do so with fewer human resources. It’s a lot easier to scale virtual network resources than it is to hire a new staff as soon as demand hits.

There is a wide range of performance benefits SDN delivers, especially if your company wants to make more data-driven business decisions.

Often, we see improvements in creating more visibility in networks, improved efficiency by automating network asset use, simpler control of secondary traffic and the ability to support new hardware thanks to a platform that’s vendor-neutral.