The Best Approach to SDN and NFV isn’t from ETSI or Open-Something, but From the MEF

I had a very interesting talk with the MEF and with their new CTO (Pascal Menezes), covering their “Third Network”, “Lifecycle Service Orchestration” and other things.  If you’ve read my stuff before, you know that there are many aspects of their strategy that I think are insightful, even compelling.  I’m even more sure about that after my call with them, and also more certain that they intend to exploit their approach fully.  I’m hoping that they can.

The Third Network notion comes because we have two networks today—the Internet which is an everybody-to-everybody open, best-efforts, fabric that mingles everything good and bad about technology or even society, and business connectivity which is more trustworthy, has an SLA, and supports an explicit and presumably trusted community.  One network will let me reach anything, do anything, in grand disorder. The other orders things and with that order comes a massive inertia that limits what I can do.

We live in a world where consumerism dominates more and more of technology, and where consumer marketing dominates even businesses.  An opportunity arises in moments, and is lost perhaps in days.  In the MEF vision (though not explicitly in their positioning) the over-the-top players (OTTs) have succeeded and threatened operators because the OTTs could use the everything-everywhere structure of the Internet to deliver service responses to new opportunities before operators could even schedule a meeting of all their stakeholders.

The operators can hardly abandon their networks, for all the obvious reasons.  They need to somehow adapt their network processes to something closer to market speed.  I think that the MEF concept of the Third Network reflects that goal nicely in a positioning sense.

At a technical level, it could look even better.  Suppose we take MEF slides at the high level as the model—the Third Network is an interconnection of provider facilities at Level 2 that creates a global fabric that rivals the Internet in reach without its connectivity promiscuity and its QoS disorder.  If you were to build services on the Third Network you could in theory have any arbitrary balance of Internet-like and Carrier-Ethernet-like properties and costs.  You could establish Network-as-a-Service (NaaS) in a meaningful sense.

In my view the obvious, logical, simple, and compelling architecture is to use the Third Network as the foundation for a set of overlay networks.  Call them Nicira-SDN-like, or call them tunnels, or virtual wires, or even SD-WANs.  Tunnels would create a service framework independent of the underlayment, which is important because we know that L2 connectivity isn’t agile or scalable on the level of the Internet.  The point is that these networks would use hosted nodal functionality combined with overlay tunnels to create any number of arbitrary connection networks on top of the Ethernet underlayment.  This model isn’t explicit in the MEF slides but their CTO says it’s their long-term goal.

A combination of overlay/underlay and an interconnected-metro model of the network of the future would be in my view incredibly insightful, and if it could be promoted effectively, it could be a revolution.  The MEF is the only body that seems to be articulating this model, and that makes them a player in next-gen infrastructure in itself.

What’s needed to make this happen?  The answer is two things, and two things only.  One is a public interconnection of Level 2 networks to create the underlayment.  The other is a place to host the nodal features needed to link the tunnels into virtual services.  We can host features at the user edge if needed, and we know how to do network-to-network interfaces (NNIs).  The operators could field both these things if they liked, but so could (and do, by the way) third parties like MSPs.

What would make this notion more valuable?  The answer is “the ability to provide distributed hosting for nodal functionality and other features”.  Thus, philosophically above our Third Network connection fabric would be a tightly coupled cloud fabric in which we could deploy whatever is needed to link tunnels into services and whatever features might be useful to supplement the basic connectivity models we can provide that way.  These, classically, are “LINE”, “LAN”, and “TREE”, which the MEF recognizes explicitly, as well as ACCESS and NNI.

If the Third Network is going to provide QoS, then it needs to support classes of service in the L2 underlayment, and be able to route tunnels for services onto the proper CoS.  If it’s going to provide security then it has to be sure that tunnels don’t interfere or cross-connect with each other, and that a node that establishes/connects tunnels doesn’t get hacked or doesn’t create interfering requests for resources.  All of that is well within the state of the art.  It also has to be able to support the deployment of nodes that can concentrate tunnel traffic internally to the network for efficiency, and also to host features beyond tunnel cross-connect if they’re useful.

You don’t need either SDN or NFV for this.  You can build this kind of structure today with today’s technology, probably at little incremental cost.  That to my view is the beauty of the Third Network.  If, over time, the needs of all those tunnels whizzing around and all that functionality hunkering down on hosting points can be met better with SDN or NFV, or cheaper with them, or both—then you justify an evolution.

What you do need in the near term is a means of orchestrating and managing the new overlay services.  Lifecycle Service Orchestration (LSO) is the MEF lifecycle process manager, but here I think they may have sunk themselves too far into the details.  Yes it is true that tunnels will have to be supported over legacy infrastructure (L2 in various forms, IP/MPLS in various forms), SDN, and NFV.  However, that should be only the bottom layer.  You need a mechanism for service-level orchestration because you’ve just created a service overlay independent of the real network.

The details of LSO are hard to pull from a slide deck, but it appears that it’s expected to act as a kind of overmind to the lower-level management and orchestration processes of NMS, SDN, and NFV.  If we presumed that there was a formal specification for the tunnel-management nodes that could be resident in the network (hosted in the cloud fabric) or distributed to endpoints (vCPE) then we could say this is a reasonable presentation of features.  The slides don’t show that, and in fact don’t show the specific elements for an overlay network—those tunnel-management nodes.

It all comes down to this, in my view.  If the MEF’s Third Network vision is that of an overlay network on top of a new global L2 infrastructure, then they need tunnel-management nodes and they need to orchestrate them at least as much as the stuff below (again, they assure me that this is coming).  You could simply let CoS do what’s needed, if you wanted minimalist work.  If they don’t define those tunnel-management nodes and don’t orchestrate them with LSO, then I think the whole Third Network thing starts to look like slideware.

The Third Network’s real state has special relevance in the seemingly endless battle over the business case for network evolution.  In my own view, the Third Network is a way of getting operators close to the model of future services that they need, without major fork-lift modernization or undue risk.  It could even be somewhat modular in terms of application to services and geographies.  Finally, it would potentially not only accommodate SDN and NFV but facilitate them—should it succeed.  If the Third Network fails, or succeeds only as a limited interconnect model, then operators will inevitably have to do something in the near term, and what they do might not lead as easily to SDN and NFV adoption.

This could be big, but as I’ve noted already the model isn’t really supported in detail by the MEF slideware, and in fact I had to have an email exchange with the CTO to get clarifications (particularly on the overlay model and overlay orchestration) to satisfy my requirement for written validation of claims.  He was happy to do that, and I think the MEF’s direction here is clear, but the current details are sparse because the long term is still a work in progress.

The MEF is working to re-invent itself, to find a mission for L2 and metro in an age that seems obsessed with virtualizing and orchestrating.  Forums compete just like vendors do, after all, and the results of some of this competition are fairly cynical.  I think that the MEF has responded to the media power of SDN and NFV, for example, by featuring those technologies in its Third Network, when the power of that approach is that it doesn’t rely on either, but could exploit both.  Their risk now lies in posturing too much and addressing too little, of slowing development of their critical and insightful overlay/underlay value proposition to blow kisses at technologies that are getting better ink.  There’s no time for that.

Whether the foundation of the Third Network was forum-competition opportunism or market-opportunity-realization is something we may never know, but frankly it would matter only if the outcome was questionable.  I’m more convinced than ever that the MEF is really on to something with the Third Network.  I hope they take it along the path they’ve indicated.