What is Network Slicing?

We have been talking about the future 5G for years, the fifth generation of mobile networks that is slowly rolling out within the next few years, but seems to be everywhere because of all the media coverage it receives. Although 5G might still be a bit far off, today it is a little closer after the first specification that standardizes it has been approved.

If each company used its own protocols, connections would be awkward and limited. Learn more about how to keep up with technology development on our blog post The Ongoing Evolution of Telecommunication Standards.

The 3rd Generation Partnership Project (3GPP), a standards organization which develops protocols for mobile telephony, has decided to accelerate the pace on the road to 5G. This first specification defines the architecture of the system, but we are going to focus on an interesting point that differentiates 5G from previous generations: Network slicing.
Network slicing is a virtual networking architecture related to software-defined networking (SDN) and network functions virtualization (NFV), two closely associated network virtualization technologies that are moving modern networks toward software-based automation. SDN and NFV allow considerably better network flexibility through the partitioning of network architectures into virtual elements. In essence, network slicing allows the creation of multiple virtual networks atop a shared physical infrastructure.
Right now, mobile networks of each operator are unique networks, which offer service to both mobiles and any other connected device with mobile connectivity. But that is not efficient, because not all devices need leading speeds or need to be continuously transmitting information, so the ones in a certain category are impacted by those in another category. Network slicing has come to put an end to this drawback.

A Subnet for Each Device

Network slicing will allow operators to create subnetworks for specific purposes: to service smartphones, MVNOs, connected vehicles, IoT, etc.
Subnets adapt better to the needs of each connected device. For example, the Internet of Things does not need high speeds but low power consumption, so a subnet dedicated to serving IoT devices could be optimized to reduce the consumption of connected devices, without reducing the offering high speeds.
This point of the definition of 5G standard could conflict with the net neutrality principle. Each subnet will have its own speed or latency conditions, so not all data will travel in the same conditions for the spectrum. This situation calls for an open debate that the authorities will have to resolve within a maximum period of two years.
All actors involved in 5G can continue with their tests and investigations with a better base. Many operators want to be the first to successfully implement 5G, and although some have already announced commercial deployments for 2019, it is more likely that we will have to wait until 2020.

Network Slicing in Action

In order to abstract the network resources from the underlying physical hardware, the control and user sphere are separated, which enables user-sphere functionality to move to the network edge, and management functionality to remain at the core. This evolved scenario allows the implementation of network slicing.

Source: Inside 5G

In this scenario, physical components are secondary and logical partitions are paramount, giving capacity to specific purposes dynamically according to need. As needs vary, so do the devoted resources. Using resources such as storage and processors, network slicing allows the creation of slices dedicated to logical, self-contained, partitioned network functions.
With network slicing, slices can be precisely configured to support certain use cases, which receive a unique set of optimized resources and network topology.

Network Slicing Is Essential to Tomorrow’s Networks

Technologies such as SDN and NFV are key to the growth that is taking place in current network architecture. Yesterday’s legacy physical infrastructures are in the process of breaking down into customizable, logical elements that can be controlled programmatically to provide custom levels of connectivity. By maximizing flexibility, network slicing is on the verge of enabling the future of connectivity.

What Is 5G Network Slicing?

Mobile and telecommunications operators are struggling to get themselves ready for the arrival of the first commercial 5G networks, expected to happen in 2020. One of the most innovative features of the 5G architecture is its dependence on 5G network slicing, which will let operators provide portions of their networks for specific customer uses cases. Each use case gets a unique set of optimized resources and network topology that suit the needs of that application.Source: ITUNews

Dynamism is Key

Vendors such as Nokia are calling it “dynamic” network slicing because operators will be able to designate these network slices quickly. In fact, one use case for dynamic network slicing that Nokia describes is in a stadium where network traffic escalates before the game starts but it’s primarily on the downlink because event-goers are downloading maps or getting information about the event that is happening in the stadium. Once the game or event begins, the traffic shifts to the uplink because people are uploading videos and photos to social media. “We envision a scenario where an operator could tailor the network based upon the traffic pattern they see in any environment,” says Jason Elliott, 5G market development manager at Nokia.

4G versus 5G

While 4G networks today can segment parts of the net to provide QoS for specific services and applications such as Voice over LTE, some argue that VoLTE is not an example of network slicing. According to Elliott, VoLTE is possible thanks to the prioritization of traffic rather than slicing network assets.
Peter Linder, head of business management at Ericsson, states that virtual private networking is not a good example of network slicing either because while operators are orchestrating specific network functions, they have to do it rigidly since it has a lot of limitations.
However, Linder adds that network slicing is possible with 4G, as network operators virtualize their network. He also says that the major difference between network slicing over 4G versus over 5G is that with 5G network slicing will add the radio. But with 5G, operators will need to consider the end device.
Ericsson is working with SK Telecom to bring network slicing to the 5G core. The collaboration was announced in 2018, and it would ensconce an element of SDN inside next-generation mobile networks.

Subnetworks Adapted to Needs

As the demands of each type of device or use case are different, each slice has its bandwidth, speed, and latency. One of the slices, developed together with Huawei, offers a virtual reality experience through Digital Twins, which reproduces real objects in the virtual environment. The slice dedicated to this service offers sufficient bandwidth and ultra-low latency that makes it possible to reproduce objects almost instantaneously.
In the second slice, Telefónica has reproduced together with Ericsson the remote assistance to a field technician within an industry environment 4.0, reproducing in high definition through glasses a real image based on virtual images. In this case, the demo seeks to demonstrate that remote assistance is possible, thanks to the low latency offered by the 5G.
Perhaps the most interesting slice, Ericsson developed together with Netsia a subnet dedicated exclusively to emergency services. It is very common that in emergency situations, such as terrorist attacks, the networks are saturated in a matter of minutes due to the high demand, affecting the communications of emergency services. With a dedicated slice for them, this problem would end, ensuring communications at all times thanks to the dedicated subnet.
This demonstration is another advancement of that 5G will not be exclusive for smartphones and other usual devices. 5G opens new doors, both in the field of IoT and remote control and therefore, a new way of business for operators is created, although the investments that the deployment will require will be greater than with the 4G.

5G Use Cases

5G promises compatibility with a wide variety of use cases, many of which are expected to justify and fund the considerably expensive development of this next generation of mobile networks.

• Connection rates of up to 10Gbps to mobile devices in the field
• Up to 1000 times more bandwidth per unit area
• Up to 100 times more connected devices
• Network availability of 99.999 percent
• Perceived network coverage of 100 percent
• Maximum of 1ms in delay of complete return from end to end (latency)
• Up to 90 percent reduction in energy use of the network

The point that receives more attention is the first, 10Gbps to the mobile user, probably because it is something that we all appreciate first-hand. However, the other performance goals are equally important for many of the new use cases that are expected to encourage the adoption of 5G. Below are use cases generally promoted as reasons why 5G mobile networks are extremely necessary.

• Access to fixed-line broadband of residential type
• Autonomous vehicles
• Better user mobility
• Broadcasting services
• Extreme communications in real time (for example, augmented reality, virtual reality)
• Critical vital services (for example, emergency services and first responders)
• Ultra-reliable communications (for example, remote health monitoring)
• Internet of Things

Marketing Challenges

Service migration that currently use their own independent wireless networks, integrated to the creation of new services that will make use of the performance of the 5G mobile network, will serve to strengthen the business case of the substantial investments that the operators of mobile networks should do to implement the new 5G technology. It may be much simpler to get users to adopt new services that cannot be served with current 3G / 4G mobile networks, than to convince users of dedicated wireless networks to switch to 5G networks. This is because they have very good reasons to have their own dedicated networks, for control, personalization, availability, reliability, security, familiarity and other optimized attributes for their particular cases. Even if it were possible, they would be complicated to serve them through the existing mobile network services.
Network Slicing will allow operators to offer virtual networks through the same physical mobile network used by other people, and will imitate it or even have better performance than the dedicated network replaced, in terms of capacity, speed, latency and, what it is more important, availability.

Virtualization

In order to rationalize substantial investments and ensure long-term financial feasibility, 5G networks must be compatible with a wide variety of revenue-generating uses, which will demand very different network service performance. This approach, depending on the case, will help ensure that a new 5G mobile network remains highly profitable for a mobile operator, but in a different way. To achieve these goals, 5G networks must be adaptable, dynamic and programmable from end to end, using virtualized mounts. This is facilitated by implementing network slices for each use case. A truly flexible 5G end-to-end mobile network would allow MNOs to offer a range of much broader communication services, built on certain existing, new or to-be-created cases, which will guarantee innovative and constant sources of income, beyond a simple connectivity and capacity.
To address the wide range of existing or new use cases in a cost-effective way, 5G mobile networks will surely be based on modular (virtualized) logical blocks instead of the traditional physical modular blocks. This will reduce the time to market of all new and innovative services, which in turn will allow them to have competitive advantages as they are the first to take the initiative.

Modular SDN and NFV

The multiple benefits promised as a result of SDN networks ultimately involve the complete abstraction of the physical network infrastructure. This allows network behavior to be adapted to service performance levels for each of the uses offered. The network slices can be implemented tailored for each of the cases offered, on the same set of physical network assets. This allows operators to deploy a single physical network capable of supporting a much wider portfolio of services, in order to diversify, extend and increase constant revenue streams, in a highly profitable manner.
NFV makes it possible for network functions to be deployed and implemented strictly by software, instead of having to buy, send, install, and activate physical devices. In fact, one of the most promising benefits of the NFV is precisely the ability to run a variety of Virtual Network Functions regardless of physical location, which means that VNFs can be deployed and run in different parts of the primary network, wherever it makes the most sense, related to performance, costs, reliability, availability, and security.

Safety Concerns

5G Network Slicing is based on the notion of sharing the same underlying physical network infrastructure through logical segmentation according to different use cases. This means that the end user should feel extremely comfortable with the fact that their network traffic is fully and completely safe from the other cases, especially in those cases of newer use, such as the emergency services mentioned above. The security challenges have to do with aspects of an adequate selection and implementation of technologies, as well as successfully addressing the concerns of those who are much more paranoid.
There is no doubt that convincing all users of the deserved use in all cases of sharing the same network will be a great challenge that operators will have to overcome, but it can be achieved as long as the 5G network is designed, segmented, and secured. The implementation of network security is one thing, but to convince certain users that their data is safe is completely different. It is possible, of course, but it will require a lot of investment in terms of time and money.

Orchestration

Mobile network operators want to deploy, manage, and offer services at the lowest possible cost without compromising the quality of service or the experience of their customers. This means that from the perspective of the provision of services, 5G networks will have to be handled automatically and well synchronized. The orchestration of the connectivity of the network service, together with the chained network functions, will require administrative, multi-domain, and multi-provider support.
Each 5G segment will imply adapted network performance for each use case, this through individual physical and logical nodes from a variety of providers. This is precisely where the concept of openness will help operators implement 5G network slices and the associated network services faster and more easily. Open and standardized software interfaces, along with a multi-domain services orchestration (MDSO), will be key to using 5G network technology focused on each case and around the different business models.
The 5G network slicing concept will be much more challenging than a VPN network as it involves a combination of many existing and emerging network technologies related to wireless, wired, RAN, EPC, SDN, NFV, optical, small cells … that will be associated with much more demanding use cases, and many of which have not yet been conceived. Regardless of the tremendous technological challenges in terms of network segmentation, many consider it the best way to justify 5G investments, since it makes possible a whole range of existing and new use cases, which justify investments in 5G today and towards the future.

If each company used its own protocols, connections would be awkward and limited. Learn more about how to keep up with technology development on our blog post The Ongoing Evolution of Telecommunication Standards.