Tag Archives: network slicing

Why 5G Won’t Be Here Tomorrow

I just saw another article yesterday written by a major-city newspaper telling the public that 5G is coming in 2020. I hate to see reporters who have accepted the nonsense being peddled by the carriers without digging a little deeper to find the truth. At some point in the near future, the public will finally realize that the 5G talk has mostly been hype.

I don’t mean to always sound like a 5G critic because over time 5G will vastly improve the cellular experience. However, many of the improvements being suggested by the cellular companies – like gigabit cellular service – may never happen. Of more immediacy is the fact that there won’t be any major improvements to cellular networks from 5G for at least 3 – 5 years. The carriers have the country and politicians fully convinced that 5G is right around the corner – but it’s not.

There was a recent article written by Sue Marek in FierceWireless that is a great example of why 5G is not going to be here tomorrow. Titled Network Slicing is a Security Nightmare for Operators, Marek explains how complicated it’s going to be to implement network slicing – perhaps the most important new aspect of 5G cellular service.

Network slicing is the ability of the cellular network to size the transmission path to exactly meet a customer’s bandwidth needs. Network slicing is one of the ways that will enable a cell site to communicate with many more customers at the same time. Today, every customer gets the same-sized data channel, meaning a lot of bandwidth is wasted when customers use less than a full channel.

Marek points out the difficult technical challenge for providing security for every slice of bandwidth. She says that getting this right is going to take two to three years. Until network slicing is viable there really is nothing that can be called 5G. The important takeaway from her article is how difficult it is to implement new technology. 5G is a drastic change from 4G in many ways. There are thirteen major changes in the 5G specification compared to 4G and implementing each of them will be a technical challenge.

What is annoying about the 5G marketing hype is that we’ve always known it would take up to a decade to fully implement 5G, just as it did to implement 4G. The cellular companies can’t seem to help themselves from overhyping new technology, but the 5G hype is many times worse than the 4G hype a decade ago. This mostly seems due to the fact that the cellular carriers decided to use the 5G hype as a way to cram through regulatory changes they’ve wanted for a long time. That forced them to really crank up the 5G rhetoric.

5G will take the same path used by all other electronic technologies – there is a tried-and-true method of introducing upgrades. New breakthroughs start in a lab. They then go to a ‘breadboard’ process where working models are developed. Once the breadboards have been thoroughly tested they go into prototype chips, which are then retested to make sure the performance made it through the conversion to silicone. Finally, the chip design is approved and the new breakthrough goes into production. At the very fastest this process might be done in 12 – 18 months, although this can take as long as three years. Breaking in new changes in the cellular world is doubly complicated because these same changes also have to be introduced into cellphone handsets.

The likely progression we’ll see for 5G is that some new aspect of the 5G specification will make it annually into chipsets. As that happens, only the newest phones will be able to use the upgrades, while earlier versions of 5G phones won’t recognize the new breakthroughs. The idea that the handset manufacturers are introducing 5G handsets in 2020 is laughable because practically none of the important 5G upgrades are yet in chip production. Those handsets will be 5G in name only (and still priced ridiculously high).

Marek is pointing out the complexity of getting 5G security right. There are dozens of other equally difficult technical challenges needed to fully realize 5G, and there are scientists in labs working on all of them. The labs will plow through all of this over time, and long after the hype is far in the past, we’ll get 5G phones that implement most of the 5G specification. It’s worth noting that there never may be a phone that meets the entire specification – because the specifications for a new technology are a wish list. It may turn out that some parts of the specification may never practically work in the field.

Network Slicing

Almost every PowerPoint I’ve seen about 5G cellular networks talks about network slicing. This is a new networking term unique to 5G. This is the second article looking at new features of 5G, with the first being a blog on Massive MIMO.

Cellular networks are now expected to make multiple simultaneous connections with different characteristics. The examples used in most presentations explain how a cellular network should be able serve traditional cellular voice, more robust cellular data, IoT monitoring and connecting to self-driving cars. Each of these applications requires connections with different bandwidth, latency, security etc. The cellular network will be expected to immediately recognize the required need and respond appropriately.

It’s a challenge because of the diverse nature of each kind of network demand. For example, an IoT network will be comprised of huge numbers of devices mostly in fixed locations and requiring small bandwidth. Contrast this with cellular data, where as we increase data speeds we’ll expect the network to deliver large amounts of bursty bandwidth to mobile devices by combining multiple channels of frequency and even signals from multiple cell sites. Demands for self-driving cars or gaming will expect large and steady bandwidth with extremely low latency. These examples are some of the primary uses for a future cell site, but there are dozens of other kinds of connections that will be needed.

The ability to design a quick response to diverse network needs is made more difficult by the fact that every market for every cellular carrier uses a different combination of spectrum blocks and different channels within the blocks. This makes it impossible to design a ‘standard’ network strategy that will work everywhere. To be effective a cellular network must combine the spectrum components available in a given network to create a homogeneous network.

Landline networks are able to handle diverse types of demands using a combination of quality of service (QoS) and techniques like virtual private networks (VPNs). QoS uses a feature called differentiated services to classify and manage different types of IP traffic like streaming video, VoIP, web surfing, etc. Many networks also then use VPN functions like IP tunneling to isolate data paths aimed at specific customers.

These same techniques are hard to apply on a cellular network. Cellular systems need a sophisticated networking solution because the network is limited at any given time by the number of channels of frequency that are not being used. We don’t worry about this on landline networks because we can flood the network with enough bandwidth to accommodate every request. To most effectively use the available bandwidth a cellular network must quickly recognize the exact nature of the bandwidth being demanded and then cobble together the most efficient use of available spectrum. Current QoS solutions can’t adequately distinguish between different types of traffic to the degree needed to make this determination.

Network slicing provides a new way to partition the spectrum on a network. In layman’s terms it performs several functions that differ from QoS. Network slicing can quickly determine the nature of a bandwidth demand. It can then create a wide range of network responses.

One of the features of network slicing is that the network can be pre-configured for different uses. For example, a portion of the network can be isolated and assigned to a single function like IoT. Even more important, new revenues can be generated by partitioning and isolating a part of the network for a single customer – a business within range of a small cell site can be sold a share of the capacity of the cell site to guarantee better service. Slicing could also segregate traffic better – for instance, a cellular carrier could isolate traffic from one of it’s MVNO partners from other traffic on the cell site.

Network slicing can also subdivide spectrum. It allows the cell site to use a portion of a channel for a given connection rather than the whole channel. Slicing off small amounts of spectrum for small bandwidth needs if far more efficient than how cell sites operate today.

Finally, network slicing introduces a lot of new data features not available with QoS. The network can customize the way it handles any particular data stream in terms of data priority, encryption, data storage, etc. The network can more easily give priority to things like law enforcement connections, or IoT signals from critical devices.