Part 3: Is Software-Defined Networking (SDN) Changing Everything?
This is the third in a series of a three blog posts on Software-Defined Technologies, which include posts on: 1) Data Centers, 2) Storage, and 3) Networks.
Software-Defined Networking is changing everything about how networking is provisioned, monitored, and supported. At a fundamental level, SDN is changing the face of data center operations and providing new opportunities to enhance cloud computing environments, integrate with enterprise data centers, and support individual IT Outsourcing providers.
SDN is designed to separate the hardware that forwards data packets (the router and data switch) from the logic that controls packet forwarding (the control plane). In SDN the decision-making that controls data forwarding is taken away from the physical switch, and given to a piece of software on a centralized server. In other words, SDN is about creating a programmable interface, similar to Software-Defined Storage, to control the network infrastructure.
To make this work, the OpenFlow protocol, which the Open Networking Foundation is in the process of standardizing across hardware devices and manufacturers, is an integral part of SDN and is used to communicate between an external controller and enabled switches. Without the OpenFlow protocol, SDN would not be possible.
The Need for a New Network Architecture
The Networking Industry, which includes data center operations, is being driven by very powerful trends in the market (e.g. mobility, server virtualization, cloud computing, and data security). These trends have caused the networking industry to reexamine traditional architectures, which are built on tiers of Ethernet switches. This traditional design made sense when client-server was dominant, but this architecture is no longer suitable for the dynamic computing and storage needs of today’s data centers.
Traditional networking technologies are extremely inadequate when compared to the current needs of the market. It is virtually impossible for traditional architectures to meet all the demands of the new computing trends that are growing and beginning to dominate the industry. Some of the key changes that are driving the need for a new network paradigm include:
- Changing traffic patterns: In traditional client-server applications, communication occurs between one client and one server. This is no longer the case. Today’s applications access different databases and servers, creating a flurry of multi-directional machine-to-machine traffic. At the same time, individual users need to access corporate resources from different types of devices, from anywhere, and at any time.
- The ‘consumerization of IT’: IT is under pressure to accommodate the increasing use of personal smartphones, tablets, and notebooks to access corporate networks. IT is required to provide support services for these devices while protecting corporate data and meeting compliance guidelines.
- The rise of cloud services: Enterprises need to access applications, infrastructure, and other IT resources in the cloud on demand and à la carte. To make matters even more challenging, cloud services must be provided in an environment of increased security and compliance. Additionally, enabling self-service provisioning, whether in a private or public cloud, requires elastic scaling of computing, storage, and network resources.
- Big Data means more bandwidth: Handling today’s ‘big data’ requires massive parallel processing on thousands of servers, all of which need network connections to each other. This trend is currently putting enormous pressure on computing networks as ‘big data’ continues to get bigger.
The changes mentioned above are exposing the limitations and weaknesses of traditional networking technologies. Existing network architectures were not designed to meet the requirements of today’s users, enterprises, and carriers. Network designers are constrained by the limitations of current networks, which include:
- Complexity of networks which must accommodate data, voice, and video on many different devices.
- Inconsistent network-wide policies required to configure thousands of devices and mechanisms.
- Inability to scale as the network becomes overly complex.
- Lack of industry-wide standards and protocols that create vendor-dependence.
Software-Defined Networking to the Rescue
SDN architecture is emerging, but has not yet become common-place. That said, there is a tremendous need for SDN and the future of networking will rely more and more on software to control and manage the devices and systems. When this happens on a larger scale, the pace of innovation for networks will accelerate as it has in the Software-Defined Storage domain. SDN promises to transform today’s traditional networks into flexible, programmable platforms with the intelligence to allocate resources dynamically and scale to support enormous data centers. SDN will also utilize virtualization technologies to support dynamic, highly automated cloud environments. SDN is certainly on its way to becoming the standard for network design in the future.
IT Outsourcing and SDN
As IT Outsourcers evolve to meet the needs of their markets, SDN will certainly be part of their growth strategies. IT Outsourcers have been and will continue to be among the earliest adopters of this technology. SDN will not only enable Outsourcing providers to be more efficient and agile, it will help them reduce costs and become more competitive.