SD-WAN

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Defining a Standard MEF 3.0 SD-WAN Service

The diagram below illustrates all of the definitive components that together help define a standard MEF 3.0 SD-WAN service. One of the key elements is the SD-WAN Edge, which is a function existing at the subscriber site, e.g. an enterprise customer premises, that connects the SD-WAN user-to-network interface (UNI) to the underlay connectivity service (UCS) UNI. This function applies policies to the IP packets entering the SD-WAN service, determining how they are classified into application flows and forwarded across the underlay connectivity services according to the policy configuration.

Much like MEF’s service standards for underlay connectivity, an SD-WAN service consists of SD-WAN end points, specifically SD-WAN Virtual Connection End Points that together form the SD-WAN Virtual Connection. These end points represent the demarcation between the responsibility of the SD-WAN service provider and the subscriber. As an overlay service, SD-WAN involves multiple underlay connectivity services. In the sample below, there are two such services, which can leverage either MEF 3.0 underlay connectivity services, like Carrier Ethernet or other services, for example, an Internet broadband service. Furthermore, a unique element of SD-WAN services is the ability to forward traffic directly to the Internet from an SD-WAN UNI, which is termed Internet Breakout.

SD-WAN Service Components

Components of an SD-WAN Service
SD-WAN User-to-Network Interface (UNI) SD-WAN Edge SD-WAN Virtual Connection (SWVC) Underlay Connectivity Service (UCS) Underlay Connectivity Service (UCS) UCS User-to-Network Interface (UNI) Tunnel Virtual Connection (TVC) SD-WAN Virtual Connection End Point (SWVC EP) SD-WAN Virtual Connection End Point (SWVC EP) SD-WAN Virtual Connection End Point (SWVC EP) Internet Breakout

SD-WAN User-to-Network Interface (UNI)

Demarcation between Service Provider and Subscriber responsibility.

SD-WAN Edge

Connects SD-WAN UNI to UCSs, maps packets to application flows, enforces policies, and selects TVC, over which to forward each flow.

SD-WAN Virtual Connection (SWVC)

Logical multipoint connection between the SD-WAN UNIs, which corresponds to the SD-WAN Service.

Underlay Connectivity Service (UCS)

Any WAN service used by the SD-WAN, e.g., MEF Ethernet Services (MEF 6.2), MEF IP Services (MEF 61.1), MPLS VPNs and Internet Access, and MEF Optical Transport Services (MEF 63).

Underlay Connectivity Service (UCS)

Any WAN service used by the SD-WAN, e.g., MEF Ethernet Services (MEF 6.2), MEF IP Services (MEF 61.1), MPLS VPNs and Internet Access, and MEF Optical Transport Services (MEF 63).

UCS User-to-Network Interface (UNI)

Demarcation between the service provider of the underlay connectivity service, and the subscriber responsibility.

Tunnel Virtual Connection (TVC)

Point-to-point paths across UCSs that compose an SD-WAN Service.

SD-WAN Virtual Connection End Point (SWVC EP)

Logical point where application-flow policies are assigned and applied.

SD-WAN Virtual Connection End Point (SWVC EP)

Logical point where application-flow policies are assigned and applied.

SD-WAN Virtual Connection End Point (SWVC EP)

Logical point where application-flow policies are assigned and applied.

Internet Breakout

Application flows forwarded from an SD-WAN UNI directly to the Internet rather than delivered to another SD-WAN UNI.

ASD-WAN User-to-Network Interface (SD-WAN UNI)
Demarcation between Service Provider and Subscriber responsibility.

BSD-WAN Edge
Connects SD-WAN UNI to UCSs, maps packets to application flows, enforces policies, and selects TVC, over which to forward each flow.

CSD-WAN Virtual Connection (SWVC)
Logical multipoint connection between the SD-WAN UNIs, which corresponds to the SD-WAN Service.

DUnderlay Connectivity Service (UCS)
Any WAN service used by the SD-WAN, e.g., MEF Ethernet Services (MEF 6.2), MEF IP Services (MEF 61.1), MPLS VPNs and Internet Access, and MEF Optical Transport Services (MEF 63).

EUCS User-to-Network Interface (UCS UNI)
Demarcation between the service provider of the underlay connectivity service, and the subscriber responsibility.

FSD-WAN Virtual Connection End Point (SWVC EP)
Logical point where application-flow policies are assigned and applied.

GTunnel Virtual Connection (TVC)
Point-to-point paths across UCSs that compose an SD-WAN Service.

HInternet Breakout
Application flows forwarded from an SD-WAN UNI directly to the Internet rather than delivered to another SD-WAN UNI.

MEF 3.0 SD-WAN Frequently Asked Questions

The SD-WAN market is one of the hottest in the communications industry, with tens of billions of dollars in revenue projected over the next 5 years.

  • The global managed SD-WAN services market is expected to reach nearly $6.4 billion by 2023 (CAGR of 42% during 2018-2023), according to Frost & Sullivan.
  • The US managed SD-WAN services market alone is projected to be $4.5 billion by 2023 (CAGR of 74% during 2018-2023), according to Vertical Systems Group.
  • IDC estimates that the global SD-WAN infrastructure market (excluding managed services) will reach $5.3 billion by 2023 due to strong enterprise demand and the embrace of SD-WAN by leading service providers seeking to provide enterprises with dynamic management of hybrid WAN connections with guaranteed QoS on a per-application basis.

Today’s SD-WAN market shares similarities to the early days of today’s estimated $US 85+billion Carrier Ethernet market before standardization and services, technology, and professional certification took hold. There is lot of excitement about performance/price advantages, greater flexibility, etc., but there is also a huge need for education and alignment on terminology to help increase market efficiencies.

MEF is the world’s leading communications industry organization shaping the direction and growth of the SD-WAN services market through standardization and certification of services, technologies, and professionals.

In July 2019, MEF published the industry’s first global standard defining an SD-WAN service and its service attributes to help accelerate SD-WAN market growth and enable creation of powerful new hybrid networking solutions optimized for digital transformation.

SD-WAN service standardization has been conducted within the context of the MEF 3.0 Global Services Framework. It is part of a transformational initiative to define, deliver, and certify a family of dynamic Carrier Ethernet (CE), Optical Transport, IP, SD-WAN, and security services orchestrated across automated networks using LSO (Lifecycle Service Orchestration) APIs.

Combining standardized SD-WAN services with dynamic high-speed underlay connectivity services will enable service providers to offer MEF 3.0 hybrid networking solutions with unprecedented user- and application-directed control over network resources and service capabilities.

SD-WAN is the way to interface policy with an intelligent software defined network. Standardization makes it easier for integration to work across multiple types of underlying transport services. In the end, the combination of standardized and orchestrated overlay and underlay services will provide a better customer experience with improved service capabilities and guaranteed resiliency.

MEF’s SD-WAN Service Attributes and Services (MEF 70) standard describes requirements for an application-aware, over-the-top WAN connectivity service that uses policies to determine how application flows are directed over multiple underlay networks irrespective of the underlay technologies or service providers who deliver them.

MEF 70, among other things, defines:

  • Service attributes that describe the externally visible behavior of an SD-WAN service as experienced by the subscriber.
  • Traffic handling rules.
  • Key technical concepts and definitions like an SD-WAN UNI, the SD-WAN Edge, SD-WAN Tunnel Virtual Connections, SD-WAN Virtual Connection End Points, and Underlay Connectivity Services.

SD-WAN standardization offers numerous benefits that will help accelerate SD-WAN market growth while improving overall customer experience with hybrid networking solutions. Key benefits include:

  • Enabling a wide range of ecosystem stakeholders to use the same terminology when buying, selling, assessing, deploying, and delivering SD-WAN services.
  • Making it easier to interface policy with intelligent underlay connectivity services to provide a better end-to-end application experience with guaranteed service resiliency.
  • Facilitating inclusion of SD-WAN services in standardized LSO architectures, thereby advancing efforts to orchestrate MEF 3.0 SD-WAN services across automated networks.
  • Paving the way for creation and implementation of certified MEF 3.0 SD-WAN services, which will give users confidence that a service meets a fundamental set of requirements.

The next phase of SD-WAN standardization currently underway – MEF W70.1 (“W” indicates work in progress) – will be of great interest to many service providers and enterprises. This work includes defining:

  • Additional service attributes for application business importance and prioritization.
  • Underlay connectivity service parameters required to deploy an SD-WAN service.

MEF also is progressing related standards work focused on:

  • Application security for SD-WAN services.
  • Information and data modeling standards that will accelerate LSO API development for SD-WAN services.
  • Intent-based networking for SD-WAN that will simplify the subscriber-to-service provider interface.

MEF’s Application Security for SD-WAN project (MEF W88) is focused on defining policy criteria and actions to protect applications (application flows) over an SD-WAN service. Work includes defining threats, security functions, and security policy terminology and attributes, and then describing what actions a security policy should take in response to certain threats.

Threats being addressed can come from within the SD-WAN subscriber’s network or externally from the Internet when connecting to public clouds and other Internet hosts. One key area the project is currently addressing is defining Zones whereby the enterprise subscriber defines a grouping of subnets, using business function naming, where unique security policies are applied. Examples of Zones include a Point-of-Sales (POS) Terminal Zone where POS terminals are segregated from the rest of the network to protect payment card transactions connecting to a data center from being scanned and information stolen. Another Zone could be a Guest Wi-Fi Zone where visitors are allowed access to the Internet but are segregated from the corporate network. For each Zone, security policies would be applied for various defense postures.

MEF’s IBN work aims to enable an SD-WAN service subscriber to set intent-related performance and security objectives and have that be translated into granular technical policies at the network level. Toward this goal, MEF is building Domain Specific Languages (DSLs) – using restricted natural languages – that will simplify APIs that sit between end-users and service providers.

Different service and technology providers will have their own pace, but companies generally will want to align to MEF 70 and follow-on standards because of the confidence that this helps instill in customers.

Dozens of service provider and technology companies already have either certified SD-WAN services and technology, contributed to standards development, participated in SD-WAN-related Proof of Concept demonstrations, and/or otherwise aligned with the SD-WAN standard. This includes players like AT&T, Comcast Business, CenturyLink, Colt, Orange Business Services, PCCW Global, Spectrum Enterprise, Telia Company, Verizon, Fortinet, VMware, Fujitsu Network Communications, Nuage Networks, Versa Networks, Infovista, Cisco, Spirent, Amdocs, Silver Peak, and other MEF member companies.

MEF’s SD-WAN standardization work already is starting to draw the attention of some big purchasers of WAN services. As an example, technical leaders at one of the largest buyers of connectivity in the world informed MEF that they are looking at aligning on MEF SD-WAN terminology, similar to what they have done with MEF-defined Carrier Ethernet.

Recent research from Heavy Reading indicates that 76% of 125 surveyed service provider professionals worldwide believe that SD-WAN services certification is “critical” or “important” for accelerating SD-WAN market growth. Seventy-three percent of this same group believe SD-WAN technology and professional certifications are also critical or important for market growth

In November 2019, MEF launched the MEF 3.0 SD-WAN Certification Program, with Spirent as the SD-WAN Authorized Certification and Test Partner (ACTP). Certification involves rigorous tests of the service attributes and requirements defined in MEF 70 and described in detail in MEF SD-WAN Certification Test Requirements (MEF 90) standard.

Seven companies participated in the MEF 3.0 SD-WAN certification pilot. In January 2020, MEF announced the first group of certified technology vendors, including Nuage Networks, Versa Networks, and Infovista. In March 2020, MEF announced that Comcast Business, PCCW Global, Spectrum Enterprise, and Telia Company are the first service providers certified for MEF 3.0 SD-WAN services.

The complete and up to date list of MEF-certified SD-WAN service providers and technology vendors is provided in the MEF Certification Registry.

Service and technology companies interested in participating in the MEF 3.0 SD-WAN Certification Program should contact us.

The MEF 3.0 SD-WAN Certification Program will be transitioning from a pilot to general availability during the next few months. We expect MEF W90 to move into the final phase of MEF membership and Board approval in 2H March 2020, with the goal of the published standard being available in mid-2020.

MEF 3.0 SD-WAN certification will evolve as additional SD-WAN standards roll out. The evolution of MEF 70 to MEF 70.1 will be accompanied shortly thereafter by an evolution of MEF 90 to MEF 90.1. We currently expect the draft MEF 70.1 standard will be available in 4Q 2020.

In November 2019, MEF announced the SD-WAN Certified Professional (MEF-SDCP) program. MEF’s SD-WAN professional certification is the industry’s only exam verifying knowledge, skills, and abilities in the domains of SD-WAN based on the MEF 70 standard as well as other fundamentals of SD-WAN solutions. This exam is designed for technically-oriented SD-WAN professionals ranging from pre-sales to network/service engineering and operational personnel in the service provider, technology vendor, and enterprise communities.

There are now more than 300 MEF-SDCPs with that number growing rapidly as service providers enlarge their SD-WAN teams to meet customer demand for managed SD-WAN services.

Click here to learn more about and register for the MEF-SDCP exam.

MEF 70.x standards define the attributes and end-to-end service.

MEF is now developing an additional standard (MEF W119) which defines a Universal SD-WAN Edge for interoperability between a proprietary SD-WAN edge product and a cloud-based edge supporting on-ramp to cloud services from any vendor solution. This project is backed by major service provider and cloud provider MEF members.

The following links offer useful information available to all industry professionals:

MEF’s Enterprise Advisory Council (EAC) offers an excellent opportunity for enterprises to learn more about and influence MEF work related to SD-WAN, application security, service automation, and other MEF 3.0 initiatives. The EAC is a collaborative council of leading enterprises designed to strengthen the channels of communications among end-users, service providers, and vendors involved in digital transformation initiatives. We have a limited number of seats remaining open on the council for large to multi-national enterprises, and participation is free. Enterprises can learn more about this program by contacting us.

More detailed information on ongoing projects relating to SD-WAN is available to MEF members on the MEF Wiki SD-WAN Hub page.

Contributions to the SD-WAN work are welcomed. Send an inquiry on our Contact Us page for more details on how you can participate.

Learn More about SD-WAN

Educational Materials

MEF 3.0 Workshop – Digital Services Expertise – New MEF SD-WAN Certified Professional (MEF-SDCP) — 2019 Nov

Product Portfolio: SD-WAN

Addressing the skills gap challenge is tantamount to successfully navigating the industry's digital transformation. MEF's SD-WAN Certified Professional designation validates the knowledge required to design, engineer, operate and solution MEF managed SD-WAN services.

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MEF 3.0 Workshop – MEF 3.0 SD-WAN Certification — 2019 Nov

Product Portfolio: SD-WAN

MEF's SD-WAN Certification serves to accelerate market adoption of managed SD-WAN services by validating compliance with industry-designed and delivered standards for delivering managed SD-WAN as well as the underlying technology.

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MEF 3.0 Workshop – MEF 3.0 SD WAN Services — 2019 Nov

Product Portfolio: SD-WAN

In July 2019, MEF published the industry’s first global standard defining an SD-WAN service and its service attributes to help accelerate SD-WAN market growth and facilitate creation of powerful new hybrid networking solutions that are optimized for digital transformation.

Learn More

MEF 3.0 SD-WAN Services — 2019 Nov

Product Portfolio: SD-WAN

Tags: Also in Mandarin, Also in Spanish

This White Paper is intended for SD-WAN Service Providers and their enterprise customers who want to understand what a standardized, managed SD-WAN service is and the benefits it brings to the industry.

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Technical Standards & SDKs

MEF 70 SD-WAN Service Attributes and Services — 2019 Jul

Product Portfolio: SD-WAN
Standard Type: Service Attributes

The SD-WAN Service Attributes and Services Standard defines the externally-visible behavior of SD-WAN Services. The Service description is based on an agreement between an SD-WAN Subscriber (the buyer) and an SD-WAN Service Provider (the seller) that includes agreement on the values of a set of SD-WAN Service Attributes defined in this document.

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What Can I Achieve with MEF 3.0 SD-WAN?

Adopting MEF 3.0 SD-WAN Services standards empowers service providers to unlock new overlay digital services potential and best adapt to the application-centric needs of your enterprise customers. Enterprises can, in turn, quickly assess and verify the foundational components and service attributes of a certified SD-WAN service to fully address business requirements. In addition, a MEF-certified SD-WAN service is future-proofed to enable dynamic and automated capabilities supporting operational and control-related interactions related to the service.

MEF 3.0 SD-WAN advantages:

  • Accelerates buying, selling, assessing and delivering SD-WAN services through common terminology.
  • Improves application experience with simplified interfacing of policy with intelligent underlay connectivity.
  • Facilitates orchestration and automation.
  • Delivers confidence that SD-WAN services meet requirements.

What the industry is saying about SD-WAN

Be In the Know

Engage in the MEF 3.0 SD-WAN Service Arena

As a MEF member, you have access to all the standards work, including incubation projects, pre-release standards, and working drafts. Engage with your industry peers and lend your voice to the SD-WAN standards development. Our current initiatives are available in the MEF 3.0 SD-WAN Service Hub on the MEF Members’ Wiki.


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