Open-source Networking Before SDN
While there has been significant coverage of SDN and the open source movement behind SDN, the reality is that open source existed within and contributed to networking in significant ways before SDN. In the early days of the Internet, many of the key Internet infrastructure applications such as Paul Vixie’s BIND (DNS) and Eric Allman’s Sendmail were open-source. Likewise, the BSD UNIX operating system and its derivatives including FreeBSD, OpenBSD, NetBSD powered a good number of network appliances and routers in the early days of the Internet—often as private modified versions that were shipped as proprietary products. And of course, Linux and its variants were also used in embedded networking devices and today continue to feature prominently on many open-source whitebox platforms.
On the networking security side, Martin Roesch’s SNORT rose to prominence in the IDS (Intrusion Detection System) realm, and was eventually acquired by Cisco. And today, BRO and Suricata join its ranks, along with many other open-source projects in the networking security realm.
And in routing, projects like XORP (eXtensible Open Routing Platform), BIRD, Quagga evolved, with Quagga gaining prominence within many large cloud service providers, and Quagga now sees its future in the Free-Range Routing (FRR) project under the auspices of the Linux Foundation.
A Brief History of SDN and NFV
Circa 2007-2008, Software Defined Networking (SDN) ushered a new era of open networking with fundamental concepts originating in academia. At that time, the focus was on OpenFlow, an emerging standard control interface and switch abstraction to enable SDN Control.
SDN (and OpenFlow) was propelled to the forefront by the formation of the Open Networking Foundation (ONF) in 2011. The ONF forged the familiar high-level SDN model that characterized Software Defined Networking by the following attributes:
- Logically centralized control
- Network programmability and intelligence
SDN was defined more rigorously by the ONF SDN architecture framework, which motivated operators, solution providers, software innovators, and integrators alike to use SDN to transform their networks.
Network Functions Virtualization (NFV) was introduced in 2012 by a series of progressive operators who from the outset recognized the need for close collaboration to realize the vision for virtualizing the carrier network. The NFV Industry Specification Group was formed in the European Telecommunications Standards Institute (ETSI) just after the seminal white paper was released in October, 2012. Today there are close to 40 operators participating in the ETSI NFV ISG, which engaged in the third phase of its work program.