Cisco once attempted to popularise fog computing as an alternative to edge computing. You are not alone if you have never heard of it. Fog computing gave rise to a new industry group called the OpenFog Consortium for a short time (because the industry needed another group with an open prefix in its name), but this was eventually absorbed into a larger association known as the Industry IoT Consortium. Fog computing was mentioned exactly zero times this week at Informa’s edge event in London.

Unfortunately, it is a better description of the edge than “the edge,” as well as a metaphor that adequately captures the industry’s confusion in this area. The expression “the edge” makes no sense at all, implying that networks have a firm boundary like a baseball field. If they do, it will be the coverage limit in rural areas, which is not the type of place where someone would want to put a lot of computing power. In contrast, fog refers to the movement and dispersal of IT resources across the entire network, from central data centres to user gadgetry.

No one in telecom is very clear if this decentralization makes sense or what form it could take. Typically, operators favor centralization. “We don’t want to put a lot of edge clouds out there,” said Terje Jensen, the head of network architecture at Norway’s Telenor, during a presentation at Informa’s London event. “We want to centralize as much as we can.”

Dotting the landscape with “edge centers,” even if it means kitting out existing premises, would probably not be cheap. Operators would presumably have to invest in additional server equipment and software licenses, at least. Unsurprisingly, then, the cheerleaders for this rearchitecting of the network include equipment vendors like Intel and software developers, whether big or small. Intel estimates the “edge silicon” market will be worth $65 billion by 2024 (it’s unclear if this means cumulative industry revenues by then, but Gartner put annual semiconductor sales at $595 billion last year).

Puking in the metaverse

There are a few reasons why an operator might do it, conceded Jensen. The most exciting is all about service improvement. By shortening the journey for a data signal between the customer and the site, an operator could reduce latency, a lag that might interfere with more advanced applications. Otherwise, virtual reality would be disorientating enough to have headset wearers puking over their omnidirectional treadmills after just a few seconds in the metaverse.

But the metaverse remains science fiction, and operators do not want to build the low-latency infrastructure for it if all the additional revenues end up with Facebook or other members of Big Tech. Today’s latency-sensitive applications do not need an edge site for every town. Three UK believes it can address customer needs for “reduced latency” through a network comprising just three big data centers and 19 edge facilities.

Other UK operators seem in broad agreement. “The fiber lengths are not as long as in the US and the incremental benefits of latency are quite small compared with large countries,” said Viraj Abhayawardhana, who works in network strategy at BT. Vodafone UK, which partners with AWS at the edge, expects to make do with a handful of edge sites, at most. So far, it has deployed only one, while its German sibling operates three.

Business customers, however, might want data processing to be done locally, according to the BT executive, at least partly to ensure they comply with data sovereignty laws. But this does not sound like an especially convincing “use case” for the telco edge. For one thing, sovereignty concerns tend to be national, not more localized (any UK data center would probably do for a UK business, regardless of location). And a company seriously worried data could fall into the wrong hands seems likelier to have its own private cloud. There could still be opportunity for a telco – but it is less clear.

The other main reason for investing in the edge is about internal efficiency. In France, Cellnex, an infrastructure owner, is helping to shift parts of a radio access network (RAN) that Bouygues operates into 100 edge facilities, for instance. But this is about centralization rather than decentralization. IT resources in the RAN usually sit at the bottom of a mast. A “cloud RAN,” as operators call it, means sucking them into a smaller number of facilities and using less IT equipment. Without suitable fiber connections back to the masts, latency becomes an issue.

As a result, Tommi Uitto, Nokia’s mobile business head, believes that many operators will consolidate only their RAN central units, which are responsible for functions that are not latency-sensitive, and leave the so-called distributed units (DUs) at masts. “Because it has real-time functions, the DU must be no more than 20 kilometres away from the cell site,” he explained in a recent interview. “In practise, it may not make sense for anyone to build a new grid of this type of edge site, which is why we believe the majority of DUs will actually reside at the cell site.”