Virtual private networks are not new in the core network. But network slicing, which allows 5G mobile networks to create end-to-end virtual private networks, is new. Up to this point, best effort has been the only possible quality of service level for mobile networks.
Network slicing creates the ability to add quality of service, end to end, for mobile devices and networks. That will allow 5G service providers to create virtual networks, operating end to end, with defined network performance or features.
Much will depend on how other trends, such as edge computing, play out. If guaranteed throughput or specified low latency are requirements, one way of satisfying those needs is to put local computing into place.
In many proposed use cases--factory automation, IoT sensors for agriculture or connected car apps--edge computing is an alternative to network slices that run through the mobile core network. A high-bandwidth local network with local servers then becomes an alternative to a network slice.
To be sure, a network slice might also be set up to connect a metro edge computing asset to “in the metro” sensors, assuring a minimum level of bandwidth and latency performance. But it might often be possible to use premises computing and local area networks to provide the required levels of bandwidth or latency performance.
About 75 percent of service provider executives surveyed by Amdocs believe the internet of things, connected cars and smart homes represent early use cases for network slicing.
About 20 percent of respondents also believe there will be network slicing use cases in industries such as mining, agriculture and health.
There are other alternatives to network slicing as well. Enterprises long have created their own VPNs for security purposes, purchased wholesale capacity or built and run their own wide-area optical networks.
So the issue is whether mobile operators will want to supply enterprise customers with control of their own network slices, or whether some functional substitute for enterprise control can be created instead. In other words, is there a possible role for network slicing as the enabler of a new type of wholesale service?
Often other service providers are the customers, and that could be attractive.
In principle, a network slice could be purchased by a mobile operator as an alternative to some other capacity arrangement, possibly with the upside of quality of service guarantees to the network edge.
Perhaps that happens in a horizontal way, as often is the case, where functions are supplied. As 3GPP defines a slice, it is “an end to end logical communication network, within a Public Land Mobile Network (PLMN) and includes the Core Network (CN) Control Plane, User Plane Network Functions and 5G Access Network (AN).”
That allows the functions necessary to create a data connection between devices and servers.
At least in principle, a private 5G network, operated by a single enterprise, on its own facilities, would offer full vertical control of the whole network. The analogy is a complete 5G network featuring only five or six cells.
Some might see this as a threat to the mobile operator wide area business. Some tend to think even a vertical 5G private network is an extrapolation of the local area network concept, and so not a threat to WAN services.
