Energy efficiency starts to rock telcos' 5G infrastructure choices

And not only because not considering their options makes them look bad

Sustainability goals such as greater energy efficiency have risen up the agenda with telecoms operators, to the point where these concerns are now claimed to be affecting network architecture decisions for the next phase of 5G deployments.

Around the globe, telcos are moving ahead with a new phase of 5G rollouts intended to realize the benefits that were promised for this next-gen cellular technology, and this calls for an overhaul of the network infrastructure itself as much as the radio access part of the system.

According to a report by 451 Research, this next generation of mobile networks are set to be disaggregated and increasingly open systems that operate more like cloud infrastructure with virtualized or containerized network functions. From a survey of telecoms operators around the globe, it found that sustainability goals such as energy efficiency are materially affecting hardware choices.

The report found that 42 percent of respondents strongly agreed that their organization is giving greater attention to the energy efficiency of 5G deployments as part of their corporate sustainability goals, with a further 31 percent moderately agreeing.

It isn't that they are doing this out of the kindness of their hearts, though, as 27 percent strongly agreed it is because of increased environmental, social and governance (ESG) scrutiny from outside stakeholders, with another 44 percent in moderate agreement. The report also mentions ongoing economic uncertainty caused by supply chain instability, and inflation as probable causes, which seems likely in light of the increases in energy prices that many countries have experienced over the past year.

When it comes to choosing infrastructure, 43 percent of survey respondents said that power efficiency is the most important feature consideration when specifying edge servers, coming ahead of concerns even such as security.

Because of the disaggregated and cloud-like character of the new networks, operators have greater choice when it comes to hardware, which increasingly means similar servers and equipment as that seen in datacenters instead of specialized vertically integrated network appliances, 451 noted, especially through initiatives such as Open RAN.

The report states that x86 servers are a natural choice for this role, but said that questions regarding energy efficiency have created "an opportunity for disruption of the status quo."

In response to a survey question, 66 percent of respondents indicated that their organization would be willing to consider an alternative platform versus an incumbent provider to support network core/edge workloads, and the top reasons given were better performance and energy efficiency gains.

451 published its report in partnership with AMD, so we are meant to think of its Epyc server chips as the alternative to the incumbent provider; the company claims that its latest 4th Gen chips can run the same workloads using fewer servers, for example.

But it could just as well be another architecture such as Arm, which is already gaining traction in the datacenter. Last year, The Register reported that NTT Docomo and NEC had conducted tests in Japan that found that Arm-based Graviton2 processors consumed 72 percent less energy compared to x86 chips when operating NEC's 5G core software as part of the NTT Docomo 5G network, for example.

According to the 451 report, even those operators that are not willing to switch kit have factored in energy efficiency into their selection, because they expect that the incumbent provider will eventually "catch up" in terms of energy performance.

The report notes other areas of innovation that are expected to contribute to power efficiency goals, including alternative energy sources, use of liquid cooling and specialized accelerators to improve performance per watt, plus radio access network features such as sleep mode, where some systems power down in response to low traffic.

Last year, the Centre for Research into Energy Demand Solutions (CREDS) published a paper indicating that although 5G technology is more power efficient than previous generations, total energy consumption by 5G networks may in fact rise.

This is partly because while 5G equipment is said to be anything up to 90 percent more efficient than 4G in terms of energy per unit of data traffic, anticipated future increases in the volume of traffic could cancel out any savings. ®