We have all heard about 5G at this point, mostly through the heady “you’ll-love-it” pieces that have been done. Not surprisingly, most of these tout features that are either never going to happen (some of the speed claims are for point-to-point millimeter-wave applications only, not for mobile users) or are still in a state of definition flux and so may not happen in the near term. The big question in 5G progress is less what the standards might be aiming for than what operator CFOs are really looking at in the near term. So I asked a bunch of CFOs or their direct reports about 5G, and here’s what I found.
Obviously, CFOs aren’t technologists, so it’s not surprising that their views are more directed at the impact of 5G on their business. It remains for the CTO, COO, and CFO to bring these benefit-biased views into harmony with technology options, or perhaps the vendors will have to do that. Certainly there’s a risk that natural alignment between CFO goals and technology choices won’t develop. The lack of that connection has hurt both SDN and NFV, after all.
The first key CFO hope for 5G is the elimination of the burdens of specialized mobile infrastructure. Mobile connectivity is supported over what’s essentially a specialized overlay network that handles signaling traffic and supports user movement across cell boundaries—the Evolved Packet Core or EPC. EPC has been a bit of a trial from the first because of its cost, and as mobile traffic and the number of mobile devices increases, the CFO sees red ink flying in great clouds.
There is a technical goal for 5G that seems connected to this, but the precise way in which 5G would address mobility is still up in the air. To actually eliminate EPC would mean dealing with mobility management in a new way, which many 5G proponents think is a given if the architecture is to make any sense. There are evolutions to IP to disconnect location from user address in a routing sense, and of course traditional overlay network technology could also address mobility more flexibly if you virtualized the elements of EPC or simply used overlay VPNs. The idea that virtual EPCs would pave the way to 5G embodies this last view (and proponents see EPC networks living inside network slices).
I think it’s premature to say that virtual EPC paves the way for 5G, given that we don’t seem to have a clear idea of what “native” or end-game 5G would look like in the area of mobility management. Since this area seems to be the top CFO priority, getting quick clarity on this point should be a priority with vendors who want to do more than support 5G trials.
The second hope CFOs have for 5G is creation of a new model of fixed access that combines fiber and 5G radio (perhaps even millimeter-wave) to more efficiently connect homes. FTTH is practical in some areas where user density is high enough, but where it isn’t the fallback has been FTTN (for “node” or “neighborhood”), with copper forming the last segment. While DSL technology has advanced considerably, it still falls short of CATV cable or fiber potential, and CFOs fear a competitive war based on capacity might force them to less profitable fixed-network deployments.
Obviously small 5G cells could be used in an FTTN deployment to reach nearby users. That doesn’t seem to demand anything revolutionary from the standards process or vendors. However, there’s also a lot of interest among CFOs for the idea that these FTTN cells would also be 5G mobile cells, leveraging the FTTN nodes to improve coverage and performance. This could be particularly valuable, according to about half the CFOs, in the IoT space for both home control and vehicular 5G.
Network slicing and perhaps function virtualization could be the technical features promoted by this goal, and I think we’re far enough along to be able to get some traction on the point in early trials—providing carriers and vendors converge on trying the application.
The third hope for 5G is creation of a single architecture for access/service networking, one that lets services live above both current and future wireless and wireline access connectivity. One reason for this is to facilitate roaming seamlessly between WiFi (local or public) and cellular networks. That issue has gotten hot since Comcast said it would be doing a WiFi-based mobile service that’s widely expected to involve MVNO relationships with some cellular providers (like Google Fi already does).
In addition to facilitating WiFi roaming, network multi-tenancy, or slicing, is a requirement to support MVNO relationships, and CFOs also think that competition is going to drive the need for those relationships as a means of reducing customer acquisition and retention costs. However, CFOs seem to think that slicing has to be extensible broadly—a kind of explicit overlay/underlay or multi-tenant structure that crosses from wireless to wireline, access to core. That vision would favor an SDN-driven transformation on a broader scale. While some vendors would surely like to see that (or should, particularly ones like ADVA or Ciena), nobody seems to be pushing it according to the CFOs.
What’s the last CFO hope for 5G? That 5G will be the last “generational” change, to launch a less dramatic evolutionary path to the future. Wireless services have evolved as a series of major lurches, each posing major changes in technology. The CFOs hope that with 5G we can make the components of mobile infrastructure more modular, so that new services and features can be introduced ad hoc, on demand.
This hope is last not because it’s narrowly held but because it’s vague. What the CFOs are concerned about is that the exploding changes driven by consumer broadband are only beginning to hit network design, and that IoT could create even more dramatic shifts in requirements. Generations, if one applies the human timeframe, are supposed to be 20 years. One CFO suggested that maybe for networking demand, 20 months was more realistic. If that’s true, then the cost of wireless modernization to keep pace would be prohibitive unless a modular-substitution model were applied.
You can kind of draw this capability from the diagrams of vendors like Ericsson, Huawei, and Nokia, but the points aren’t explicit. I think the biggest problem in creating an explicit evolution-versus-generation plan is the lack of a specific model that represents where 5G itself would be starting. We can envision backward compatibility with LTE, but what is LTE then being compatible with? It has to be more than consuming a slice of 5G; what does 5G itself do without the LTE slice?
The single-architecture goal doesn’t mean that CFOs think 5G is a fork-lift upgrade or an all-or-nothing proposition. In fact, their hope is that its modularity will mean that it will be possible to introduce 5G for limited missions, with the single-architecture attribute insuring that no matter where you start, you end up in the right place. I think CFOs have felt that way about SDN and NFV as well, and I hope their aspirations are more easily met with 5G.
