I’ve blogged often on the importance of 5G function hosting to the deployment of edge computing. If operators were to create a “carrier cloud” to host virtual functions for 5G and other service missions, the resource pool created could then be available to host generalized edge applications. That could advance edge computing significantly.
It may the risk that operators would become edge and cloud players that’s been motivating cloud providers to pursue carrier cloud hosting as an alternative to operator build-outs. It may simply be a desire to grab some incremental revenue to sustain cloud growth, and of course it may be a combination of the two. Nevertheless, operators and cloud providers aren’t the only players who are interested, The big mobile network infrastructure vendors are also working in the space, perhaps to accommodate what emerges and perhaps to attempt to influence things in a direction that favors their own business models. Light Reading has a story on this.
None of the mobile infrastructure players are really pushing edge computing products of their own. Thus, they have to see the battle between cloud-provider-hosted and operator-deployed edge resources something that influences their own sales in a more indirect way. The way that seems most obvious is the link between cloud-provider 5G support, Open RAN, and open-model networking in general. Our Things Past and Things to Come podcast for October 3rd talks a bit about open-model networking, but not about this specific linkage.
The 3GPP 5G specifications divide mobile networks into a “control plane” and a “user plane”, as our podcast notes. The user plane represents IP network infrastructure, something that’s not likely to be hosted as virtual functions because custom devices (routers) are far better packet-pushers. The control plane is the smarts of mobile networks, and it’s more like a cloud application set. That makes it a logical target for cloud hosting, whether it’s in carrier cloud or in a public cloud provider. Open RAN initiative, and open 5G Core implementations that similarly separate control and user plane, address a generalized framework for control-plane hosting, and cloud providers can gain traction by adopting open-source software and standards for the 5G control plane. If they succeed, then they encourage open-model networks, and that’s perhaps a threat to the big mobile infrastructure vendors.
Ericsson, featured in the Light Reading piece, may be especially concerned here. While Ericsson has been at least supportive of open 5G initiatives, they’ve not been as firmly linked with them as competitor Nokia. Nokia’s business has outperformed Ericsson’s, which surely puts pressure on the latter company. More support for open-model 5G could end up increasing that pressure, or forcing Ericsson to belatedly jump into the concept with both feet, behind their rival.
It’s not only Ericsson that’s at risk here, though. If operators adopt any cloud form of 5G control plane it could spur integration and a true open-model 5G implementation, providing that the cloud was used to host any suitable implementation of the 5G control plane. If the operators select a public cloud vendor’s implementation rather than simply host software on a public cloud provider, it would have the opposite effect because that could stifle interest in any 5G control plane implementation that wasn’t selected to serve as a public-cloud 5G element.
A true open-model 5G wouldn’t favor the big mobile infrastructure vendors. An open-model 5G defined by the software selection of the public cloud providers could make a mockery of “open” and substitute cloud lock-in for vendor lock-in. Not an attractive set of options, but if one or the other isn’t going to prevail by default, somebody has to do something. Ericsson? We can’t be sure.
Ericsson is quoted as saying that the 5G CU and DU should run in a dedicated server, and that operators like Rakuten “does not recommend placing core network operations – those requiring low-latency connections between radios and DUs – into the public cloud.” The fact is that it’s doubtful the public cloud would be deployed far out enough toward the mobile edge to even carry that traffic. The broader question IMHO is whether a separation of user and control planes could separate CU and DU functionality similarly, and allow for cloud hosting of the control piece. This might require some specialized white-box software to push the bits.
The reason I say we can’t be sure whether Ericsson sees all of this is that the story doesn’t talk about the control/user plane separation, and doesn’t question Ericsson on the topic. But if Ericsson is willing to say that it would use Dell servers to host the CU/DU, why not say they’d support a specialized white-box element combined with a control-plane function hosted elsewhere?
Is it feasible to “run a 5G network” inside a public cloud? Frankly, I don’t think so. The user plane traffic is not the kind of event/transactional stuff public clouds are designed to support. The charges for traffic ingress/egress would be daunting, and making the whole thing reliable enough is probably something that’s not being thought much about, and possibly could not be done consistent with cost constraints. Is it feasible to run the control plane inside a public cloud? Yes, but if we want to do that then we have to view both the 3GPP and O-RAN work as tentative because neither really thinks about white boxes.
White box switching is increasingly a missing ingredient in advanced network infrastructure standardization and planning. We talk about “hosting” functions without regard for the fact that hosting means servers and servers don’t mean a lot of traffic-handling. White box switches could “host” functions too, and any networking standards or strategies that don’t recognize and accommodate that truth is selling the whole notion of open networks short.
The primary requirement for white-box function hosting is less a part of the white box or even white-box platform, but a representation in the deployment and lifecycle management tools to be used. Clearly, if 5G networks are to be “deployed” and managed on open resources, we need to have unified lifecycle operations support or the opex costs could overwhelm capex savings.
The cloud used to be all about x86/x64 hosting. We added ARM and GPUs, and I think it’s inevitable that we add white boxes in as well. The cloud is also the primary driver of network change, both from the supply and demand side, and networks will always be primarily supported through specialized white-box devices. Without adding these to the cloud, at least in terms of making them an element in deploying virtual functions, our concept of the cloud and edge computing could both be crippled.