There is a tremendous amount of buzz about 5G cellular services. Most of the talk is about the great data speeds that the platform will offer. That buzz, of course, is warranted. But the most exciting thing about 5G just may be a change that is not as obvious as speed numbers.
At the highest level, 5G is being designed in a use-case-based approach. In the past, the goal of planners was to offer a certain amount of bandwidth and the tools to enable it to be delivered with the level of reliability for which end users were willing to pay. It was a broad mandate.
5G is a bit different. It is being designed, from the ground up, with an eye toward enabling services with specific characteristics to be created.
Consider three possible uses of 5G:
- Supporting internet of things sensors monitoring refrigerated containers on trucks that send a warning if the temperature passes a certain point
- Facilitating voice, video and data communications between first responders
- Managing autonomous vehicles
These tasks are fundamentally different. Only one (the first responders) requires a tremendous amount of bandwidth. Advising a dispatcher that the strawberries are getting a tad toasty or telling a car that it may not be a good idea to switch lanes isn’t data intensive. The difference between these two uses is that it doesn’t matter if the news about the fruit comes at 3:01:5 p.m. or 3:02:15. That is a big deal, however, when the car is about to make its move.
The point is that 5G will be used for many different purposes and the needs in terms of throughput, latency, jitter, prioritization and perhaps others will be all over the map. 5G is being designed with this in mind.
In the 5G network slicing environment, a company in the fruit transport business can order services that fit its needs (low throughput; low priority). The same for municipalities and their first responders (high throughput; high priority) and companies managing autonomous vehicles (low throughput; high priority). Creating these use cases is done via an approach called network slicing. As the name implies, this is the use of a bit of network capacity to virtualize everything needed to provide a network service.
It’s a tricky thing, since it involves fitting as many of these virtualized services as possible into a given amount of bandwidth. Each network sliced-based service must be capable of providing all the service level agreements (SLAs) and assorted bells and whistles of traditionally provisioned services. InterDigital vice president Alan Carlton wrote at Computerworld that network slicing is a fundamentally different and deeper approach than virtual private networks and DiffServ, which are used to guarantee bandwidth. The main difference is that network slicing adds dedicated storage and computing assets to the bandwidth itself.
Packet Design CT Cengiz Alaettinoglu provides good insight into network slicing. It is important to note, he writes, that network slicing – which is being developed by the 3rd Generation Partnership Project (3GPP) – won’t be finalized until next year. Everything that is said about it now is at least somewhat speculative.
That being said, the technology train is far enough down the road that engineers and developers can safely make certain assumptions. Details will change, but the basic concept is set. The package of assets that Carlton referred to is described by Alaettinoglu as including routers and links (which he groups as network resources), compute and storage. He writes that orchestrating all of these slices in such a manner that the promised services are delivered is a challenging task.
Another way to think of network slicing is that it is taking the trend of the past few years – virtualization – all the way to the end user device. This is how TM Forum's Dawn Bushaus put it at Wireless Week: "Operators can already create network slices in a virtualized 4G mobile core, but 5G adds the capability in the radio access portion of the network. This makes it possible to create a slice at the edge for a low-power application where sensors have limited battery power or for a very low-latency, high bandwidth application like augmented reality."
5G is a very exciting new technology. The glitziest element to the public almost certainly is the pure speeds that will become available. Ask a network engineer or a product development executive what excites them, however, and the answer likely will be that network slicing is the most attractive capability introduced by the new platform.