- 3.1 Evolving Network Requirements
- 3.2 The SDN Approach
- 3.3 SDN- and NFV-Related Standards
- 3.4 Key Terms
3.3 SDN- and NFV-Related Standards
Unlike some technology areas, such as Wi-Fi, there is no single standards body responsible for developing open standards for SDN and NFV. Rather, there is a large and evolving collection of standards-developing organizations (SDOs), industrial consortia, and open development initiatives involved in creating standards and guidelines for SDN and NFV. Table 3.1 lists the main SDOs and other organizations involved in the effort and the main outcomes so far produced. This section covers some of the most prominent efforts.
TABLE 3.1 SDN and NFV Open Standards Activities
Organization |
Mission |
SDN- and NFV-Related Effort |
Open Networking Foundation (ONF) |
An industry consortium dedicated to the promotion and adoption of SDN through open standard development. |
OpenFlow |
Internet Engineering Task Force (IETF) |
The Internet’s technical standards body. Produces RFCs and Internet standards. |
Interface to routing systems (I2RS) Service function chaining |
European Telecommunications Standards Institute (ETSI) |
An EU-sponsored standards organization that produces globally applicable standards for information and communications technologies. |
NFV architecture |
OpenDaylight |
A collaborative project under the auspices of the Linux Foundation. |
OpenDaylight |
International Telecommunication Union — Telecommunication Standardization Sector (ITU-T) |
United Nations agency that produces Recommendations with a view to standardizing telecommunications on a worldwide basis. |
SDN functional requirements and architecture |
Internet Research Task Force (IRTF) Software Defined Networking Research Group (SDNRG) |
Research group within IRTF. Produces SDN-related RFCs. |
SDN architecture |
Broadband Forum (BBF) |
Industry consortium developing broadband packet networking specifications. |
Requirements and framework for SDN in telecommunications broadband networks |
Metro Ethernet Forum (MEF) |
Industry consortium that promotes the use of Ethernet for metropolitan and wide-area applications. |
Defining APIs for service orchestration over SDN and NFV |
IEEE 802 |
An IEEE committee responsible for developing standards for LANs. |
Standardize SDN capabilities on access networks. |
Optical Internetworking Forum (OIF) |
Industry consortium promoting development and deployment of interoperable networking solutions and services for optical networking products. |
Requirements on transport networks in SDN architectures |
Open Data Center Alliance (ODCA) |
Consortium of leading IT organizations developing interoperable solutions and services for cloud computing. |
SDN usage model |
Alliance for Telecommunications Industry Solutions (ATIS) |
A standards organization that develops standards for the unified communications (UC) industry. |
Operational opportunities and challenges of SDN/NFV programmable infrastructure |
Open Platform for NFV (OPNFV) |
An open source project focused on accelerating the evolution of NFV. |
NFV infrastructure |
Standards-Developing Organizations
The Internet Society, ITU-T, and ETSI are all making key contributions to the standardization of SDN and NFV.
Internet Society
A number of standards-developing organizations (SDOs) are looking at various aspects of SDN. Perhaps the most active are two groups within the Internet Society (ISOC): IETF and IRTF. ISOC is the coordinating committee for Internet design, engineering, and management. Areas covered include the operation of the Internet itself and the standardization of protocols used by end systems on the Internet for interoperability. Various organizations under the ISOC are responsible for the actual work of standards development and publication.
The Internet Engineering Task Force (IETF) has working groups developing SDN-related specifications in the following areas:
- Interface to routing systems (I2RS): Develop capabilities to interact with routers and routing protocols to apply routing policies.
- Service function chaining: Develop an architecture and capabilities for controllers to direct subsets of traffic across the network in such a way that each virtual service platform sees only the traffic it must work with.
The Internet Research Task Force (IRTF) has published Software-Defined Networking (SDN): Layers and Architecture Terminology (RFC 7426, January 2015). The document provides a concise reference that reflects current approaches regarding the SDN layer architecture. The Request For Comments (RFC) also provides a useful discussion of the southbound API (Figure 3.3) and describes some specific APIs, such as for I2RS.
IRTF also sponsors the Software Defined Networking Research Group (SDNRG). This group investigates SDN from various perspectives with the goal of identifying the approaches that can be defined, deployed, and used in the near term and identifying future research challenges.
ITU-T
The International Telecommunication Union—Telecommunication Standardization Sector (ITU-T) is a UN agency that issues standards, called recommendations, in the telecommunications area. So far, their only published contribution to SDN is Recommendation Y.3300 (Framework of Software-Defined Networking, June 2014). The document addresses definitions, objectives, high-level capabilities, requirements, and high-level architecture of SDN. It provides a valuable framework for standards development.
ITU-T has established a Joint Coordination Activity on Software-Defined Networking (JCA-SDN) and begun work on developing SDN-related standards.
Four ITU-T study groups (SGs) are involved in SDN-related activities:
- SG 13 (Future networks, including cloud computing, mobile, and next-generation networks): This is the lead study group of SDN in ITU-T and developed Y.3300. This group is studying SDN and virtualization aspects for next-generation networks (NGNs).
- SG 11 (Signaling requirements, protocols, and test specifications): This group is studying the framework for SDN signaling and how to apply SDN technologies for IPv6.
- SG 15 (Transport, access, and home): This group looks at optical transport networks, access networks, and home networks. The group is investigating transport aspects of SDN, aligned with the Open Network Foundation’s SDN architecture.
- SG 16 (Multimedia): This group is evaluating OpenFlow as a protocol to control multimedia packet flows, and is studying virtual content delivery networks.
European Telecommunications Standards Institute
ETSI is recognized by the European Union as a European Standards Organization. However, this not-for-profit SDO has member organizations worldwide and its standards have international impact.
ETSI has taken the lead role in defining standards for NFV. ETSI’s Network Functions Virtualisation (NFV) Industry Specification Group (ISG) began work in January 2013 and produced a first set of specifications in January 2015. The 11 specifications include an NFV’s architecture, infrastructure, service quality metrics, management and orchestration, resiliency requirements, and security guidance.
Industry Consortia
Consortia for open standards began to appear in the late 1980s. There was a growing feeling within private-sector multinational companies that the SDOs acted too slowly to provide useful standards in the fast-paced world of technology. Recently, a number of consortia have become involved in the development of SDN and NFV standards. We mention here three of the most significant efforts.
- See Chapter 4, “SDN Data Plane and OpenFlow”
By far the most important consortium involved in SDN standardization is the Open Networking Foundation (ONF). ONF is an industry consortium dedicated to the promotion and adoption of SDN through open standards development. Its most important contribution to date is the OpenFlow protocol and API. The OpenFlow protocol is the first standard interface specifically designed for SDN and is already being deployed in a variety of networks and networking products, both hardware based and software based. The standard enables networks to evolve by giving logically centralized control software the power to modify the behavior of network devices through a well-defined “forwarding instruction set.” Chapter 4 is devoted to this protocol.
The Open Data Center Alliance (ODCA) is a consortium of leading global IT organizations dedicated to accelerating adoption of interoperable solutions and services for cloud computing. Through the development of usage models for SDN and NFV, ODCA is defining requirements for SDN and NFV cloud deployment.
The Alliance for Telecommunications Industry Solutions (ATIS) is a membership organization that provides the tools necessary for the industry to identify standards, guidelines, and operating procedures that make the interoperability of existing and emerging telecommunications products and services possible. Although ATIS is accredited by ANSI, it is best viewed as a consortium rather than an SDO. So far, ATIS has issued a document that identifies operational issues and opportunities associated with increasing programmability of the infrastructure using SDN and NFV.
Open Development Initiatives
There are a number of other organizations that are not specifically created by industry members and are not official bodies such as SDOs. Generally, these organizations are user created and driven and have a particular focus, always with the goal of developing open standards or open source software. A number of such groups have become active in SDN and NFV standardization. This section lists three of the most significant efforts.
OpenDaylight
OpenDaylight is an open source software activity under the auspices of the Linux foundation. Its member companies provide resources to develop an SDN controller for a wide range of applications. Although the core membership consists of companies, individual developers and users can also participate, so OpenDaylight is more in the nature of an open development initiative than a consortium. ODL also supports network programmability via southbound protocols, a bunch of programmable network services, a collection of northbound APIs, and a set of applications.
- See Section 5.3, “Open-Daylight”
OpenDaylight is composed of about 30 projects, and releases their outputs in simultaneous manner. After its first release, Hydrogen, in February 2014, it successfully delivered the second one, Helium, at the end of September 2014.
Open Platform for NFV
Open Platform for NFV is an open source project dedicated to acceleration the adoption of standardized NFV elements. OPNFV will establish a carrier-grade, integrated, open source reference platform that industry peers will build together to advance the evolution of NFV and to ensure consistency, performance, and interoperability among multiple open source components. Because multiple open source NFV building blocks already exist, OPNFV will work with upstream projects to coordinate continuous integration and testing while filling development gaps.
- See Section 7.4, “NFV Benefits and Requirements”
OpenStack
OpenStack is an open source software project that aims to produce an open source cloud operating system. It provides multitenant Infrastructure as a Service (IaaS), and aims to meets the needs of public and private clouds regardless of size, by being simple to implement and massively scalable. SDN technology is expected to contribute to its networking part, and to make the cloud operating system more efficient, flexible, and reliable.
OpenStack is composed of a number of projects. One of them, Neutron, is dedicated for networking. It provides Network as a Service (NaaS) to other OpenStack services. Almost all SDN controllers have provided plug-ins for Neutron, and through them services on OpenStack and other OpenStack services can build rich networking topologies and can configure advanced network policies in the cloud.