Decoding SDN
Welcome, NC
Posted on: Jul 28, 2014
Compiled by The Juniper Networks SDN Team
For the past year, software-defined networking (SDN) has been the buzz of the networking world. But in many ways, networking has always been defined by software. Software is pervasive within all of the technology that impacts our lives and networking is no different. However, networks have been constrained by the way software has been configured, delivered and managed - literally within a box, updated monolithically, managed through command lines that are throw-back to the days of mini-computers and DOS in the 1980’s.
THE CHALLENGES WITH NETWORKING SOFTWARE
In the service provider world, carriers struggle to configure and manage their networks. Like Google, they too have built operational support systems to configure their networks but these systems are often 20+ years old and they are crumbling from the burden placed upon them by networking software. For a service provider, the network is their business, so they must look to networking vendors to introduce new capabilities in order to enable new business opportunities. Here again, networking software is failing the industry - it is developed as a monolithic, embedded system and there is no concept of an application. Every new capability requires an update of the entire software stack. Imagine needing to update the OS on your smartphone every time you load a new application. Yet that is what the networking industry imposes on its customers. What’s worse is that each update often comes with many other changes - and these changes sometimes introduce new problems. So service providers must carefully and exhaustively test each and every update before they introduce it into their networks.
WHAT IS SDN?
Service providers are seeking solutions to their networking challenges. They want their networks to adjust and respond dynamically, based on their business policy. They want those policies to be automated so that they can reduce the manual work and personnel cost of running their net- works. They want to quickly deploy and run new applications within and on top of their networks so that they can deliver business results. And they want to do this in a way that allows them to introduce these new capabilities without disrupting their business. This is a tall order but SDN has the promise to deliver solutions to these challenges. How can SDN do this? To decode and understand SDN, we must look inside networking software. From this understanding, we can derive the principles for fixing the problems. This is what SDN is all about.
Here are six principles of SDN with corresponding customer benefits:
- Cleanly separate networking software into four layers (planes): Management, Services, Control, and Forwarding - providing the architectural underpinning to optimize each plane within the network.
- Centralize the appropriate aspects of the Management, Services and Control planes to simplify network design and lower operating costs.
- Use the Cloud for elastic scale and flexible deployment, enabling usage-based pricing to reduce time to service and correlate cost based on value.
- Create a platform for network applications, services, and integration into management systems, enabling new business solutions.
- Standardize protocols for interoperable, heterogeneous support across vendors, providing choice and lowering cost.
- Broadly apply SDN principles to all networking and network services including security - from the data center and enterprise campus to the mobile and wireline networks used by service providers.