Giving telecom networks a computing edge

Operators have long sought to provide their users with a consistent quality of service. For cellular it is why ubiquitous cellular coverage is important, for example.

But a subtler approach is taking hold as networks evolve whereby what a user does will change depending on their location. And what will enable this is edge computing.

 Source: Senza Fili Consulting

Edge computing

“This is an entirely new concept,” says Monica Paolini, president and founder at Senza Fili Consulting. “It is a way to think about service which is going to have a profound impact.”

Edge computing has emerged as a consequence of operators virtualising their networks. Virtualisation of network functions hosted in the cloud has promoted a trend to move telecom functionality to the network core. Functionality does not need to be centralised but initially, that has been the trend, says Paolini, especially given how virtualisation promotes the idea that network location no longer matters.

“That is a good story, it delivers a lot of cost savings,” says Paolini, who recently published a report on edge computing. * 

But a realisation has emerged across the industry that location does matter; centralisation may save the operator some costs but it can impact performance. Depending on the application, it makes sense to move servers and storage closer to the network edge.

The result has been several industry initiatives. One is Mobile Edge Computing (MEC) being developed by the European Telecommunications Standards Institute (ETSI). In March, ETSI renamed the Industry Specification Group undertaking the work to Multi-access Edge Computing to reflect the operators requirements beyond just cellular.

“What Multi-access Edge Computing does is move some of the core functionality from a central location to the edge,” says Paolini.

Another initiative is M-CORD, the mobile component of the Central Office Re-architected as a Datacenter initiative, overseen by the Open Networks Labs non-profit organisation. Other initiatives Paolini highlights include the Open Compute Project, Open Edge Computing and the Telecom Infra Project. 

This is an entirely new concept. It is a way to think about service which is going to have a profound impact.

Location

The exact location of the ‘edge’ where the servers and storage reside is not straightforward.

In general, edge computing is located somewhere between the radio access network (RAN) and the network core. Putting everything at the RAN is one extreme but that would lead to huge duplication of hardware and exceed what RAN locations can support. Equally, edge computing has arisen in response to the limitations of putting too much functionality in the core.   

The matter of location is blurred further when one considers that the RAN itself is movable to the core using the Cloud RAN architecture.

Paolini cites another reason why the location of edge computing is not well defined: the industry does not yet know. And it will only be in the next year or two when operators start trialling the technology. “There is going to be some trial and error by the operators,” she says.

Use cases

An enterprise located across a campus is one example use of edge computing, given how much of the content generated stays on-campus. If the bulk of voice calls and data stay local, sending traffic to the core and back makes little sense. There are also security benefits keeping data local. An enterprise may also use the edge computing to run services locally and share them across networks, for example using cellular or Wi-Fi for calls.

Another example is to install edge computing at a sports stadium, not only to store video of the game’s play locally - again avoiding going to the core and back with content - but also to cache video from games taking place elsewhere for viewing by attending fans.

Virtual reality and augmented reality are other applications that require low-latency, another performance benefit of having local computation.

Paolini expects the uptake of edge computing to be gradual. She also points to its challenging business case, or at least how operators typically assess a business case may not tell the full story.

Operators view investing in edge computing as an extra cost but Paolini argues that operators need to look carefully at the financial benefits. Edge computing delivers better utilisation of the network and lower latency. “The initial cost for multi-access edge computing is compensated for by the improved utilisation of the existing network,” she says.

When Paolini started the report it was to research low-latency and the issues of distributed network design, reliability and redundancy. But she soon realised that multi-access edge computing was something broader and that edge computing is beyond what ETSI is doing.

This is not like an operator rolling out LTE and reporting to shareholders how much of the population now has coverage. “It is a very different business to learn how to use networks better,” says Paolini.  

* Click here to access the report, Power at the edge. MEC, edge computing, and the prominence of location